Accelerated partial-breast irradiation using intensity-modulated proton radiotherapy: do uncertainties outweigh potential benefits?

OBJECTIVE: Passive scattering proton beam (PSPB) radiotherapy for accelerated partial-breast irradiation (APBI) provides superior dosimetry for APBI three-dimensional conformal photon radiotherapy (3DCRT). Here we examine the potential incremental benefit of intensity-modulated proton radiotherapy (IMPT) for APBI and compare its dosimetry with PSPB and 3DCRT. METHODS: Two theoretical IMPT plans, TANGENT_PAIR and TANGENT_ENFACE, were created for 11 patients previously treated with 3DCRT APBI and were compared with PSPB and 3DCRT plans for the same CT data sets. The impact of range, motion and set-up uncertainties as well as scanned spot mismatching between fields of IMPT plans was evaluated. RESULTS: IMPT plans for APBI were significantly better regarding breast skin sparing (p<0.005) and other normal tissue sparing than 3DCRT plans (p<0.01) with comparable target coverage (p=ns). IMPT plans were statistically better than PSPB plans regarding breast skin (p<0.002) and non-target breast (p<0.007) in higher dose regions but worse or comparable in lower dose regions. IMPT plans using TANGENT_ENFACE were superior to that using TANGENT_PAIR in terms of target coverage (p<0.003) and normal tissue sparing (p<0.05) in low-dose regions. IMPT uncertainties were demonstrated for multiple causes. Qualitative comparison of dose-volume histogram confidence intervals for IMPT suggests that numeric gains may be offset by IMPT uncertainties. CONCLUSION: Using current clinical dosimetry, PSPB provides excellent dosimetry compared with 3DCRT with fewer uncertainties compared with IMPT. ADVANCES IN KNOWLEDGE: As currently delivered in the clinic, PSPB planning for APBI provides as good or better dosimetry than IMPT with less uncertainty.

A custom three-dimensional electron bolus technique for optimization of postmastectomy irradiation.

PURPOSE: Postmastectomy irradiation (PMI) is a technically complex treatment requiring consideration of the primary tumor location, possible risk of internal mammary node involvement, varying chest wall thicknesses secondary to surgical defects or body habitus, and risk of damaging normal underlying structures. In this report, we describe the application of a customized three-dimensional (3D) electron bolus technique for delivering PMI. METHODS AND MATERIALS: A customized electron bolus was designed using a 3D planning system. Computed tomography (CT) images of each patient were obtained in treatment position and the volume to be treated was identified. The distal surface of the wax bolus matched the skin surface, and the proximal surface was designed to conform to the 90% isodose surface to the distal surface of the planning target volume (PTV). Dose was calculated with a pencil-beam algorithm correcting for patient heterogeneity. The bolus was then fabricated from modeling wax using a computer-controlled milling device. To aid in quality assurance, CT images with the bolus in place were generated and the dose distribution was computed using these images. RESULTS: This technique optimized the dose distribution while minimizing irradiation of normal tissues. The use of a single anterior field eliminated field junction sites. Two patients who benefited from this option are described: one with altered chest wall geometry (congenital pectus excavatum), and one with recurrent disease in the medial chest wall and internal mammary chain (IMC) area. CONCLUSION: The use of custom 3D electron bolus for PMI is an effective method for optimizing dose delivery. The radiation dose distribution is highly conformal, dose heterogeneity is reduced compared to standard techniques in certain suboptimal settings, and excellent immediate outcome is obtained.

Relationship of sentinel and axillary level I-II lymph nodes to tangential fields used in breast irradiation.

PURPOSE: To evaluate the volume of nodal irradiation associated with breast-conserving therapy, we defined the anatomic relationship of sentinel lymph nodes and axillary level I and II lymph nodes in patients receiving tangential breast irradiation. METHODS AND MATERIALS: A retrospective analysis of 65 simulation fields in women with breast cancer treated with sentinel lymph node surgery and 39 women in whom radiopaque clips demarcated the extent of axillary lymph node dissection was performed. We measured the relationship of the surgical clips to the anatomic landmarks and calculated the percentage of prescribed dose delivered to the sentinel lymph node region. RESULTS: A cranial field edge 2.0 cm below the humeral head the sentinel lymph node region was included or at the field edge in 95% of the cases and the entire extent of axillary I and II dissection in 43% of the axillary dissection cases. In the remaining 57%, this field border encompassed an average of 80% of cranial/caudal extent of axillary level I and II dissection. In 98.5% of the cases, all sentinel lymph nodes were anterior to the deep field edge and 71% were anterior to the chest wall-interface, whereas 61% of the axillary dissection cohort had extension deep to the chest wall-lung interface. If the deep field edge had been set 2 cm below the chest wall-lung interface, the entire axillary dissection would have been included in 82% of the cases, and the entire sentinel lymph node would have been covered with a 0.5-cm margin. The median dose to the sentinel lymph node region was 98% of the prescribed dose. CONCLUSIONS: By extending the cranial border to 2 cm below the humeral head and 2 cm deep to the chest wall-lung interface, the radiotherapy fields used to treat the breast can include the sentinel lymph node region and most of axillary levels I and II.

The influence of pathologic tumor characteristics on locoregional recurrence rates following mastectomy.

PURPOSE: The objective of this study was to evaluate the influence of pathologic factors other than tumor size and number of involved axillary nodes on the risk of locoregional recurrence (LRR) following mastectomy. PATIENTS AND METHODS: We reviewed the medical records of 1031 patients treated with mastectomy and doxorubicin-based chemotherapy without radiation on 5 prospective clinical trials. Median follow-up was 116 months (range, 6-262 months). RESULTS: Patients with gross multicentric disease were at increased risk of LRR (37% at 10 years). However, patients with multifocal disease and those with microscopic multicentric disease did not experience higher rates of LRR than those with single lesions (17% at 10 years). Patients with lymph-vascular space invasion (LVSI) or involvement of the skin or nipple also experienced high rates of LRR (25%, 32%, and 50%, respectively). The presence of close (<5 mm) or positive margins was associated with an increased risk of LRR (45%). The increased risk of LRR observed for patients with pectoral fascial invasion (33%) was not reduced when negative deep margins were obtained. On multivariate analysis, the presence of 4 or more involved axillary nodes, tumor size of greater than 5 cm, close or positive surgical margins, and gross multicentric disease were found to be independent predictors of LRR (all, p < 0.01). In a separate analysis including only patients with 1-3 involved axillary nodes, microscopic invasion of the skin or nipple, pectoral fascial invasion, and the presence of close or positive margins were significant predictors of LRR. CONCLUSION: In addition to the extent of primary and nodal disease, other factors that predict for high rates of LRR include the presence of LVSI, involvement of the skin, nipple or pectoral fascia, close or positive margins, or gross multicentric disease. These factors predict for high LRR rates regardless of the number of involved axillary nodes.

Recursive partitioning analysis of locoregional recurrence patterns following mastectomy: implications for adjuvant irradiation.

PURPOSE: Postmastectomy irradiation improves overall survival for breast cancer patients at high risk for locoregional recurrence (LRR). The objective of this study was to use recursive partitioning analysis (RPA) to define patient subgroups at high risk for LRR following mastectomy. PATIENTS AND METHODS: A cohort of 1031 patients treated on prospective trials with mastectomy and doxorubicin-based chemotherapy without irradiation was analyzed. The variables considered in the RPA were tumor size, number of involved nodes, number of nodes examined, and percentage of nodes involved (nodes involved/nodes examined). The endpoint was LRR +/- distant metastasis. Only patients with complete data were analyzed (n = 913). Median follow-up was 8 years (range, 0.7-22 years). RESULTS: Involvement of 20% or more of the lymph nodes examined was the most significant variable predicting LRR. Three risk categories were defined. Patients with 20% or more involved nodes and tumors of 3.5 cm or more were at greatest risk for LRR (41% at 8 years). An intermediate-risk group included patients with 20% or more involved nodes and tumors of less than 3.5 cm as well as those with less than 20% involved nodes and tumor size of 5 cm or greater (18% at 8 years). Patients with less than 20% involved nodes and tumor size of less than 5 cm were at lowest risk for LRR (10% at 8 years). CONCLUSION: Tumor size and extent of nodal involvement play interrelated roles in predicting LRR following mastectomy and systemic therapy. Patients with 20% or greater involved nodes and those with less than 20% nodes and tumors of 5.0 cm or greater are at significant risk of LRR and should be considered for postoperative irradiation.

Impact of systemic treatment on local control for patients with lymph node-negative breast cancer treated with breast-conservation therapy.

PURPOSE: To determine the impact of tamoxifen and chemotherapy on local control for breast cancer patients treated with breast-conservation therapy. PATIENTS AND METHODS: The data from 484 breast cancer patients who were treated with breast-conserving surgery and radiation were analyzed. Only patients with lymph node-negative disease were studied to provide comparative groups with a similar stage of disease and a similar competing risk for distant metastases. Actuarial local control rates of the 277 patients treated with systemic therapy (128, chemotherapy with or without tamoxifen; 149, tamoxifen alone) were compared with the rates for the 207 patients who received no systemic treatment. Only 10% of the patients had positive (2%), close (3%), or unknown margin status (5%). RESULTS: Patients treated with systemic therapy had improved 5-year (97.5% v 89.8%) and 8-year (95.6% v 85.2%) local control rates compared with those that did not receive systemic treatment (P =.004, log-rank test). There was no statistical difference in local control between patients treated with chemotherapy and patients treated with tamoxifen alone (P =.219). Systemic treatment, margin status, young patient age, estrogen and progesterone receptor status, and primary tumor size were analyzed in a Cox regression analysis. The use of systemic treatment was the most powerful predictor of local control: patients who did not receive systemic treatment had a relative risk of local recurrence of 3.3 (95% confidence interval, 1.5 to 7.5; P =.004). CONCLUSION: In this retrospective analysis, systemic therapy appears to contribute to long-term local control in patients with lymph node-negative breast cancer treated with breast-conservation therapy.

Coronary artery dosimetry in intact left breast irradiation.

PURPOSE: The purpose of this article is to report dose-volume histograms of coronary vessels from irradiation of the intact left breast. PATIENTS AND METHODS: Fifteen women with cancer of the left breast underwent computed tomographic treatment planning for radiation treatments of an intact left breast. Images through the heart were reconstructed at 1-mm increments to permit contouring of the coronary vessels. Five treatment plans were created for each patient; one plan from the simulated treatment fields and four additional plans that were generated from virtual treatment fields created by shifting the isocenter 5 mm and 10 mm both superficially and deep. The radiation dose was calculated using a three-dimensional treatment planning system that incorporated heterogeneity correction factors. RESULTS: With no adjustment to the perpendicular lung distance, a mean volume of 12% of the left anterior descending coronary artery received 20 Gy, 6% received 30 Gy, and 3% received 40 Gy. The dose to the left anterior descending coronary artery varied significantly with changes in the perpendicular lung distance. From the mean perpendicular lung distance of 1.87 for the simulated fields, a 5-mm increase in the perpendicular lung distance resulted in an increase of 20%, 15%, and 12% in the percentage of the left anterior descending coronary artery treated to 20 Gy, 30 Gy, and 40 Gy, respectively. With a 10-mm increase, the respective volumes were increased to 49%, 41%, and 34%, respectively. A 5-mm reduction of lung distance in the original plan resulted in a decrease of 10%, 5%, and 3% in the percentage treated to 20 Gy, 30 Gy, and 40 Gy, respectively. The dose to the left main coronary artery, the right main coronary artery, and the left circumflex coronary artery was limited to scatter and was less than 7 Gy. Changes in the perpendicular lung distance did not significantly affect the dose administered to these vessels. DISCUSSION: The left anterior descending coronary artery is anatomically located at the edge of the cardiac silhouette on traditional treatment films. Small changes in the perpendicular lung distance can significantly change the dose delivered to this vessel. A fundamental change in the shape of the dose-volume histogram occurs at a perpendicular lung distance of 2.3 cm, whereas the dose is very low when the perpendicular lung distance is less than 1.3 cm. These points may serve as clinically important values in the treatment planning for cancer of an intact breast.

Local-regional control in breast cancer patients with a possible genetic predisposition.

PURPOSE: Local control rates for breast cancer in genetically predisposed women are poorly defined. Because such a small percentage of breast cancer patients have proven germline mutations, surrogates, such as a family history for breast cancer, have been used to examine this issue. The purpose of this study was to evaluate local-regional control following breast conservation therapy (BCT) in patients with bilateral breast cancer and a breast cancer family history. METHODS AND MATERIALS: We retrospectively reviewed records of all 58 patients with bilateral breast cancer and a breast cancer family history treated in our institution between 1959 and 1998. The primary surgical treatment was a breast-conserving procedure in 55 of the 116 breast cancer cases and a mastectomy in 61. The median follow-up was 68 months for the BCT patients and 57 months for the mastectomy-treated patients. RESULTS: Eight local-regional recurrences occurred in the 55 cases treated with BCT, resulting in 5- and 10-year actuarial local-regional control rates of 86% and 76%, respectively. In the nine cases that did not receive radiation as a component of their BCT, four developed local-regional recurrences (5- and 10-year local-regional control rates of BCT without radiation: 49% and 49%). The 5- and 10-year actuarial local-regional control rates for the 46 cases treated with BCT and radiation were 94% and 83%, respectively. In these cases, there were two late local recurrences, developing at 8 years and 9 years, respectively. A log rank comparison of radiation versus no radiation actuarial data was significant at p = 0.009. In the cases treated with BCT, a multivariate analysis of radiation use, patient age, degree of family history, margin status, and stage revealed that only the use of radiation was associated with improved local control (Cox regression analysis p = 0.021). The 10-year actuarial rates of local-regional control following mastectomy with and without radiation were 91% and 89%, respectively. CONCLUSIONS: Patients with a possible genetic predisposition to breast cancer had low 5-year rates of local recurrence when treated with breast conserving surgery and radiation, but the local failure rate exceeded 50% when radiation was omitted. Our data are consistent with the hypothesis that patients with an underlying genetic predisposition develop cancers with radiosensitive phenotypes.

Ductal carcinoma-in-situ: long-term results of breast-conserving therapy.

BACKGROUND: The role of breast-conserving therapy (BCT) in the management of ductal carcinoma-in-situ (DCIS) is controversial because of reported high recurrence rates. We reviewed our experience to determine whether the rate and pattern of locoregional recurrence after BCT were similar in patients with DCIS and patients with early-stage (T1) invasive breast tumors and whether local recurrence affected survival. METHODS: Between 1973 and 1994, 87 patients with DCIS alone, 22 patients with DCIS with microinvasion (DCIS-M), and 646 patients with invasive breast cancer 2 cm or smaller in diameter were treated with BCT (wide local excision with radiotherapy) at The University of Texas M. D. Anderson Cancer Center. Survival was calculated by the Kaplan-Meier method. The median follow-up times were 11 years for patients with DCIS alone, 12 years for patients with DCIS-M, and 8 years for patients with invasive breast cancer. RESULTS: Eleven (13%) of 87 patients with DCIS and 5 (23%) of 22 patients with DCIS-M had developed locoregional recurrences at follow-up. Two patients with DCIS with locoregional recurrence died of breast cancer. Of the 646 patients with invasive breast cancer, 56 (9%) had a locoregional recurrence, and 16 (2%) died of breast cancer. The median time to locoregional recurrence was significantly longer in patients with DCIS or DCIS-M (9-10 years) than patients with invasive tumors (5 years). CONCLUSIONS: DCIS is a favorable disease with an excellent long-term survival. The locoregional recurrence rate in patients with DCIS treated with BCT is similar to that in patients with early-stage invasive breast cancer treated with BCT, but time to locoregional recurrence is significantly longer in patients with DCIS. In patients with DCIS treated with BCT, intense surveillance for locoregional recurrence needs to be maintained for the patient's lifetime.

Locoregional recurrence patterns after mastectomy and doxorubicin-based chemotherapy: implications for postoperative irradiation.

PURPOSE: The objective of this study was to determine locoregional recurrence (LRR) patterns after mastectomy and doxorubicin-based chemotherapy to define subgroups of patients who might benefit from adjuvant irradiation. PATIENTS AND METHODS: A total of 1,031 patients were treated with mastectomy and doxorubicin-based chemotherapy without irradiation on five prospective trials. Median follow-up time was 116 months. Rates of isolated and total LRR (+/- distant metastasis) were calculated by Kaplan-Meier analysis. RESULTS: The 10-year actuarial rates of isolated LRR were 4%, 10%, 21%, and 22% for patients with zero, one to three, four to nine, or >/= 10 involved nodes, respectively (P <.0001). Chest wall (68%) and supraclavicular nodes (41%) were the most common sites of LRR. T stage (P <.001), tumor size (P <.001), and >/= 2-mm extranodal extension (P <.001) were also predictive of LRR. Separate analysis was performed for patients with T1 or T2 primary disease and one to three involved nodes (n = 404). Those with fewer than 10 nodes examined were at increased risk of LRR compared with those with >/= 10 nodes examined (24% v 11%; P =.02). Patients with tumor size greater than 4.0 cm or extranodal extension >/= 2 mm experienced rates of isolated LRR in excess of 20%. Each of these factors continued to significantly predict for LRR in multivariate analysis by Cox logistic regression. CONCLUSION: Patients with tumors >/= 4 cm or at least four involved nodes experience LRR rates in excess of 20% and should be offered adjuvant irradiation. Additionally, patients with one to three involved nodes and large tumors, extranodal extension >/= 2 mm, or inadequate axillary dissections experience high rates of LRR and may benefit from postmastectomy irradiation.

Prognostic implications of pathological lymph node status after preoperative chemotherapy for operable T3N0M0 breast cancer.

BACKGROUND: Although preoperative chemotherapy has become the standard of care for inoperable locally advanced breast cancer, its role for downstaging resectable primary tumors is still evolving. The purpose of this study was to determine whether the prognostic information from an axillary node dissection in patients with clinical T3N0 breast cancer was altered by preoperative chemotherapy compared with surgery de novo. METHODS: Between 1976 and 1994, 91 patients with clinically node-negative operable T3 breast cancer received doxorubicin-based combination chemotherapy on protocol at one institution. Fifty-three patients received both preoperative and postoperative chemotherapy (PreopCT), and 38 received postoperative chemotherapy only (PostopCT). All patients underwent axillary lymph node dissection as part of their definitive surgical treatment. There were no differences between the PreopCT and PostopCT groups in median age (51 vs. 49 years), median tumor size at presentation (6 cm vs. 6 cm), tumor grade, or estrogen receptor status (estrogen receptor negative 38% vs. 32%). The median follow-up time was 7 years. RESULTS: Patients in the PreopCT group had fewer histologically positive lymph nodes (median, 0 vs. 3, P < .01), and a lower incidence of extranodal extension (19% vs. 42%, P = .02). By univariate analysis, the number of pathologically positive lymph nodes (P < .01) and extranodal extension (P < .01) were predictors of disease-specific survival in PreopCT patients. Multivariate analysis showed that extranodal extension was the only independent prognostic factor in PreopCT patients (P < .01). Overall, PreopCT and PostopCT patients had similar 5-year disease-free survival rates (66% vs. 57%); however, PreopCT patients had worse disease-free (P = .01) and disease-specific survival (P = .04) when survival was compared after adjustment for the number of positive lymph nodes. Furthermore, PreopCT patients with 4-9 positive lymph nodes had a lower 5-year disease-free survival rate than PostopCT patients with 4-9 positive nodes (17 vs. 48%, P = .04). CONCLUSIONS: Axillary lymph node status remains prognostic after chemotherapy. Pathologically positive lymph nodes after preoperative chemotherapy are associated with a worse prognosis than the same nodal status before chemotherapy.

Locoregional irradiation for inflammatory breast cancer: effectiveness of dose escalation in decreasing recurrence.

PURPOSE: To evaluate the effect of radiation dose escalation on locoregional control, overall survival, and long-term complication in patients with inflammatory breast cancer. PATIENTS AND METHODS: From September 1977 to December 1993, 115 patients with nonmetastatic inflammatory breast cancer were treated with curative intent at The University of Texas M. D. Anderson Cancer Center. The usual sequence of multimodal treatment consisted of induction FAC or FACVP chemotherapy, mastectomy (if the tumor was operable), further chemotherapy, and radiation therapy to the chest wall and draining lymphatics. Sixty-one patients treated from September 1977 to September 1985 received a maximal radiation dose of 60 Gy to the chest wall and 45-50 Gy to the regional lymph nodes, 22 treated once a day at 2 Gy per fraction, and 35 were treated b.i.d. (32 after mastectomy and all chemotherapy was completed, and 2 immediately after mastectomy; one patient had distant metastases discovered during b.i.d. irradiation, and treatment was stopped). Four additional patients received preoperative radiation with standard fractionation. Based on the analysis of the failure patterns of the patients, the dose was increased for the b.i.d. patients in the new series, with 51 Gy delivered to the chest wall and regional nodes, followed by a 15-Gy boost to the chest wall with electrons. From January 1986 to December 1993, 39 patients were treated b.i.d. to this higher dose after mastectomy and all the chemotherapy was completed; and 8 additional patients received preoperative irradiation with b.i.d. fractionation to 51 Gy. During this period, another 7 patients were treated using standard daily doses of 2 Gy per fraction to a total of 60 Gy, either because they had a complete response or minimal residual disease at mastectomy or because their work schedule did not permit the b.i.d. regimen. Comparison was made between the groups for locoregional control, disease-free and overall survival, and complication rates. RESULTS: The median follow-up time was 5.7 years (range, 1.8-17.6 years). For the entire patient group, the 5- and 10-year local control rates were 73.2% and 67.1%, respectively. The 5- and 10-year disease-free survival rates were 32.0% and 28.8%, respectively, and the overall survival rates for the entire group were 40.5% and 31.3%, respectively. To evaluate the effectiveness of dose escalation, a specific comparison of patients who received b.i.d. radiation after mastectomy and completion of adjuvant chemotherapy was performed. There were 32 patients treated b.i.d. to 60 Gy in the old series versus 39 patients treated b.i.d. to 66 Gy in the new series. There was an significant improvement in the rate of locoregional control for the b.i.d. patients for the old vs. new series, from 57.8% to 84.3% and from 57.8% to 77.0% (p = 0.028) at 5 and 10 years, respectively. Chemotherapy regimens did not change significantly during this time period.Long-term complications of radiation, such as arm edema more than 3 cm (7 patients), rib fracture (10 patients), severe chest wall fibrosis (4 patients), and symptomatic pneumonitis (5 patients), were comparable in the two groups, indicating that the dose escalation did not result in increased morbidity. Significant differences in the rates of locoregional control (p = 0.03) and overall survival (p = 0.03), and a trend of better disease-free survival (p = 0.06) were also observed that favored the recently treated patients receiving the higher doses of irradiation. CONCLUSION: Twice-daily postmastectomy radiation to a total of 66 Gy for patients with inflammatory breast cancer resulted in improved locoregional control, disease free survival, and overall survival, and was well tolerated.

Synchronous primary cancers of the breast and cervix: planning multidisciplinary primary treatment [clinico-pathological conference].

Multiple metachronous primary malignancies are becoming increasingly frequent; however, multiple synchronous primary malignancies are still unusual. We report the case of a 61-year-old woman with synchronous stage IIIB ductal carcinoma of the left breast and FIGO stage IB2 squamous cell carcinoma of the cervix. The patient was treated initially every 4 weeks with a 24-h intravenous infusion of paclitaxel (175 mg/m2) followed by a 1-h infusion of carboplatin (area under the curve of 5 mg/ml x min) with concurrent irradiation of the pelvis. Significant toxic reactions including nausea, vomiting, and diarrhea required hospitalization or outpatient intravenous fluids and antiemetics. After four cycles of chemotherapy, the breast cancer was in complete clinical remission, and the patient underwent a modified radical mastectomy with axillary lymph node dissection. Pathologic findings revealed a few microscopic foci of residual infiltrating ductal carcinoma exhibiting a marked treatment effect; none of the 14 axillary lymph nodes removed showed evidence of metastatic tumor. A near-complete pathologic response of the breast cancer and a complete clinical response of the cervical cancer were obtained. Adjuvant chemotherapy for the breast cancer was then initiated, followed by radiation and hormonal therapy.

Randomized trial of high-dose chemotherapy and blood cell autografts for high-risk primary breast carcinoma.

BACKGROUND: Uncontrolled studies have reported encouraging outcomes for patients with high-risk primary breast cancer treated with high-dose chemotherapy and autologous hematopoietic stem cell support. We conducted a prospective randomized trial to compare standard-dose chemotherapy with the same therapy followed by high-dose chemotherapy. PATIENTS AND METHODS: Patients with 10 or more positive axillary lymph nodes after primary breast surgery or patients with four or more positive lymph nodes after four cycles of primary (neoadjuvant) chemotherapy were eligible. All patients were to receive eight cycles of 5-fluorouracil, doxorubicin (Adriamycin), and cyclophosphamide (FAC). Patients were stratified by stage and randomly assigned to receive two cycles of high-dose cyclophosphamide, etoposide, and cisplatin with autologous hematopoietic stem cell support or no additional chemotherapy. Tamoxifen was planned for postmenopausal patients with estrogen receptor-positive tumors and chest wall radiotherapy was planned for all. All P values are from two-sided tests. RESULTS: Seventy-eight patients (48 after primary surgery and 30 after primary chemotherapy) were registered. Thirty-nine patients were randomly assigned to FAC and 39 to FAC followed by high-dose chemotherapy. After a median follow-up of 6.5 years, there have been 41 relapses. In intention-to-treat analyses, estimated 3-year relapse-free survival rates were 62% and 48% for FAC and FAC/high-dose chemotherapy, respectively (P =.35), and 3-year survival rates were 77% and 58%, respectively (P =.23). Overall, there was greater and more frequent morbidity associated with high-dose chemotherapy than with FAC; there was one septic death associated with high-dose chemotherapy. CONCLUSIONS: No relapse-free or overall survival advantage was associated with the use of high-dose chemotherapy, and morbidity was increased with its use. Thus, high-dose chemotherapy is not indicated outside a clinical trial.

Importance of radiation therapy for breast cancer patients treated with high-dose chemotherapy and stem cell transplant.

PURPOSE: To determine local-regional failure rates in breast cancer patients treated with surgery and high-dose chemotherapy with stem cell transplant and to relate local-regional failure to the use and timing of radiation treatment. METHODS AND MATERIALS: We retrospectively reviewed the records of 165 breast cancer patients treated on institutional protocols with surgery and high-dose chemotherapy with stem cell transplant. All patients had either Stage III disease, 10 or more positive axillary lymph nodes, or 4 or more positive axillary lymph nodes following neoadjuvant chemotherapy. Twelve patients had inflammatory breast cancer. Thirteen patients treated with breast preservation and 5 patients who died from toxicity within 30 days of transplant were excluded from the analyses of local-regional recurrences. In the remaining 147 patients, 108 were treated with adjuvant radiation and 39 were not. The disease stage distribution for these two groups was comparable. The median follow-up for surviving patients was 35 months. RESULTS: The 3- and 5-year actuarial disease-free survival (DFS) for the entire group was 60% and 51%, respectively. The 5-year rates of freedom from isolated local-regional recurrence were 95% in the patients treated with adjuvant radiation and 86% in the patients who did not receive radiation (p = 0.014, log rank comparison). The 5-year rates of any local-regional recurrence as a first event (isolated recurrences plus those with simultaneous local-regional and distant recurrences) were 92% versus 82%, respectively for patients whose treatment did and did not include radiation (p = 0.038). We could not demonstrate a correlation of the timing of radiation with the risk of local-regional recurrence. CONCLUSIONS: These data indicate that high-dose chemotherapy does not negate the importance of radiation in optimizing local-regional control in patients with high-risk breast cancer. Given the results of recent randomized trials studying postmastectomy radiation, which show that improving local-regional control improves overall survival (OS), we believe that all breast cancer patients with high-risk primary breast cancer who are treated with high-dose chemotherapy with stem cell transplant should receive radiation as a component of their treatment.

US-guided implantation of metallic markers for permanent localization of the tumor bed in patients with breast cancer who undergo preoperative chemotherapy.

Metallic markers were implanted with ultrasonographic guidance in 51 malignant breast tumors in 49 patients to tag the tumor bed in anticipation of complete or almost complete response to preoperative neoadjuvant induction chemotherapy before breast-conservation surgery. The markers were the only remaining evidence of the original tumor site in 47% (23 of 49) of the patients preoperatively. This technique effectively addresses the problem of preoperative localization of the tumor bed in complete or nearly complete response of breast cancer to neoadjuvant chemotherapy.

Nickel release from orthodontic arch wires and cellular immune response to various nickel concentrations.

AIMS: Results from two previous clinical studies suggested that exposure to high nickel-containing orthodontic arch wires may induce hypersensitivity in certain individuals. The purpose of this study was to measure the amount of nickel released from three types of nickel-containing arch wires into a synthetic saliva in vitro, and determine if the concentrations were sufficient to elicit either cytotoxic (trypan blue exclusion test) or stimulatory (MTT test) responses in human peripheral blood mononuclear cells (PBMCs) derived from nickel-sensitive and nickel-nonsensitive individuals. PBMCs were exposed to five concentrations of nickel sulfate solutions ranging from 0-29 ppm, and results were compared, particularly at concentrations obtained from nickel release experiments. FINDINGS: The amount of nickel released into synthetic saliva ranged from 0.4-4.1 ppb. Wires subjected to a combination of soaking and cyclic straining released significantly more nickel than those that were soaked only (p

Postmastectomy irradiation: rationale for treatment field selection.

The goal of postmastectomy irradiation is to eliminate residual viable tumor in tissue remaining after standard mastectomy. Because this subclinical disease is, by definition, not detectable by current technology, the choice of patients and treatment volumes for postmastectomy irradiation must be inferred from a variety of data sources. The absolute risk of locoregional recurrence is related to the stage of disease, the extent of lymphatic involvement, and other treatment received. Patterns of failure analyses consistently identify the chest wall as the most important target for treatment with radiation therapy in high-risk patients. When patients with multiple locoregional sites of recurrence are included, the chest wall may be involved in as many as 60% to 80% of patients. The second most common place for locoregional failure is the undissected lymphatics of the paraclavicular region. The cumulative probability of failure in this region ranges from 10% to 35% of the patients treated for locoregional recurrence. Microscopic tumor metastases in the internal mammary chain are theorized to represent a potential source for distant metastases. Each of the prospective trials of postmastectomy irradiation that have shown survival benefit included the internal mammary chain within their target volume. Nonetheless, local failure in the internal mammary nodes is an uncommon finding. Similarly, after a level I and II axillary dissection, axillary failure is a minor component of local recurrence risk, and it is probable that only a subset of patients may benefit from axillary irradiation.

Sequencing of chemotherapy and radiation in lymph node-negative breast cancer.

PURPOSE: To conduct a retrospective analysis of chemotherapy and radiation sequencing in lymph node-negative breast cancer patients treated with breast-conserving surgery. PATIENTS AND METHODS: Between February 1982 and January 1996, 124 patients with lymph node-negative breast cancer underwent breast-conserving surgery with axillary dissection followed by chemotherapy and radiation therapy. The outcome of 68 patients who received chemotherapy first was compared with that of 56 patients who received radiation first. The two groups were balanced with respect to patient age, tumor stage, margin status, and estrogen and progesterone receptor status. Sixty-two percent of the patients had T1 primary disease. The median follow-up among surviving patients was 44 months for the chemotherapy-first group and 61 months for the radiation-first group. RESULTS: There were no statistically significant differences in local control, disease-free survival, or overall survival between the two groups. Five-year actuarial rates for local control for the chemotherapy-first and the radiation-first groups were 100% and 94%, respectively. Five-year recurrence-free rates for the chemotherapy-first and radiation-first groups were 92% and 77%, respectively. The 5-year overall survival rate was 89% for both groups. DISCUSSION: Giving chemotherapy before radiation in lymph node-negative breast cancer did not compromise local control. Given the concerns about increased distant metastases if radiation is given first, the chemotherapy-radiation sequence is recommended.

Tumor suppressor genes and breast cancer.

The genetic determinants for most breast cancer cases remain elusive. However, a mutation in a tumor suppressor gene, such as p53, BRCA1, BRCA2, or ATM, has been determined to be one mechanism of breast carcinogenesis. It has been established that inherited mutations in p53, BRCA1, and BRCA2 significantly contribute to breast cancer risk, although the importance of an inherited ATM mutation is controversial. Sporadic mutations in p53 are also common in breast cancer cells. The precise deficiencies that result from these genetic mutations have yet to be fully described. Although the functions of these genes are different, they are all involved in the maintenance of genomic stability after DNA damage. Mutations that impair the function of these four genes may adversely affect the manner in which DNA damage is processed. It is likely that the risk of breast cancer development is increased through this mechanism. In this article, we review the relevancy of p53, BRCA1, BRCA2, and ATM mutations to breast cancer development, and review the in vitro, in vivo, and clinical data exploring the mechanisms by which these mutations affect genomic integrity and DNA damage repair.