Radiotherapy for parotid cancer.

BACKGROUND: Parotid malignancies represent a heterogeneous group of tumors primarily managed by surgical extirpation. Moderately high recurrence rates are seen after surgery alone, and postoperative radiotherapy has been used for patients with higher risks for local failure. METHODS: To assess the role of radiotherapy in the management of patients with malignant tumors of the parotid gland, the records of 68 patients receiving megavoltage therapy at our institution from 1966 to 1989 were reviewed. Patients were placed into three groups for analyses. Group I was composed of 41 patients receiving radiotherapy following total gross removal of parotid cancer by surgical procedures, varying from excisional biopsy through total parotidectomy. Radiation dose for this group ranged from 4,995 to 6,500 cGy. Group II was composed of 10 patients treated with radiotherapy after incisional biopsy or excision with positive margins. These patients received radiation doses of 4,000-9,470 cGy. Group III was composed of 17 patients receiving radiotherapy for a postsurgical local recurrence. Their radiation dose ranged from 4,300 to 8,400 cGy. RESULTS: Two of the 41 patients from group I developed a local recurrence. Two of these patients also developed distant metastases, one concurrent. Two of 10 group II patients failed locally, whereas three developed distant metastases. Only nine of the 17 patients in group III were controlled locally, and four patients developed distant dissemination. CONCLUSION: Total gross excision of parotid cancer, sparing facial nerve if possible and followed by regional radiotherapy, provides excellent rates of local control and survival with modest toxicity. Patients presenting postoperatively with gross residual tumor or recurrence after surgery should be considered for trials of more aggressive treatment with combined chemotherapy or altered fractionation schemes of irradiation.

Advances in radiation therapy for head and neck cancer.

Radiation therapy either as a single modality or as part of multimodality plans remains an integral part of curative treatment for cancers of the head and neck. This paper traces the modernization of radiation therapy regarding tumors of the head and neck using examples of sites of malignancy where radiation therapy is the sole modality or where radiation therapy can be combined with surgery and chemotherapy for optimal results. As local-regional control rates have improved with the use of combined radiation therapy and surgery and aggressive hyperfractionation schemes for advanced primary tumors, distant metastases and second primary neoplasms are now accounting for a larger proportion of treatment failures. Until such time as more effective systemic therapy and cancer control mechanisms are developed to address these problems, radiation therapy will continue to play a major role in the overall management of patients with cancers of the head and neck.

MRI assisted treatment planning for radiation therapy of the head and neck.

Improved visualization of head and neck tumors has been demonstrated with the use of magnetic resonance imaging (MRI). Using standard plastic radiation therapy immobilization casts and an MR positive surface marker system developed in this institution, we have utilized MRI as an adjunct to the simulation of complex radiation treatments for tumors of the head and neck. This technique includes an indirect display of field margins and/or isodose curves over selected MR images. The lack of induced artifact from the immobilization cast, improved delineation of tumor extension from normal anatomy and the ability to image in arbitrary planes without changing patient positioning favor the use of MR over CT for radiation therapy planning in the head and neck, while ensuring reproducibility of the treatment plan at subsequent therapy sessions.

Management of elderly patients with primary breast cancer.

From 1974 through 1983, three hundred forty-three patients aged 70 years or older at diagnosis received comprehensive post-operative radiation therapy for localized (Stage I-III) breast cancer following surgical procedures ranging from incisional biopsies to classical radical mastectomy. The 5- and 10-year overall survival rates for this series of elderly patients are 67% and 33%. The respective disease-free survival rates are 67% and 42%. Over one-half of these women were treated by less than total mastectomy. No differences were seen in survival, disease-free survival, or local regional control rates comparing similarly staged patients treated by radical mastectomy, modified radical mastectomy, or tylectomy. Complications were few and seen primarily in those patients subjected to axillary dissection prior to irradiation. Long term survival appears to be achievable in the majority of elderly patients with regionally confined disease at presentation and aggressive treatment with curative intent is warranted. These elderly patients are often poor candidates for radical surgery. In this patient population, conservative surgery with post-operative radiation therapy is well tolerated and provides equivalent results to more radical surgical procedures.

Locally advanced breast carcinoma: results with combined regional therapy.

To define optimal regional treatment as initial management of locally advanced (Stage III & IV) breast cancer, 509 patients treated from 1966-1982 were reviewed. All patients received comprehensive postoperative irradiation of the peripheral lymphatics and chest wall, following surgical procedures varying from incisional biopsy to classical radical mastectomy. Patients were followed from 1 to over 16 years. The survival rate at 5 and 10 years for the entire series is 41% and 26%. Fifty-eight patients having radical surgery for T3 tumors and subsequently found to have negative axillary lymph nodes showed the highest rates of survival, 72% at 5 years and 57% at 10 years. This was significantly better (p less than .01) than patients with T3N+ disease, (5 year survival 44%; 10 year, 29%) and T4N+ disease (44%, 39%). Four hundred seventy patients with non-inflammatory carcinoma and no supraclavicular metastases were considered technically resectable. Three hundred eighty-one of these patients underwent a definitive surgical procedure removing all gross cancer prior to irradiation and, as expected, showed higher rates of local disease control than patients having lesser surgery (79% versus 45%, p less than .01). These patients also showed markedly better rates of survival and relapse-free survival with 50% alive and 38% disease free, versus 14 and 8%, at 5 years (p less than .01). There were no 10 year survivors among the 89 technically resectable patients having less than total gross resection. Long term relapse-free survival of locally advanced breast cancer can be achieved with aggressive combined local-regional therapy. Total resection of all gross cancer prior to irradiation is recommended. Modifications of postoperative radiation therapy techniques are suggested to further improve local control rates for these advanced tumors. This large series provides a baseline for evaluation of current programs adding adjuvant systemic therapy to regional treatment.

Myometrial penetration of endometrial carcinoma as a prognostic factor for patients receiving pre- or postoperative radiation therapy.

From 1966-1980, 227 patients with Stage I endometrial carcinoma were treated by total abdominal hysterectomy, bilateral salpingo-oophorectomy, and either pre- or postoperative external beam pelvic irradiation. All therapy was delivered with megavoltage equipment. There was at least a 4-week interval between irradiation and surgery for 164 patients treated preoperatively. No significant differences were found in subsequent survival or local control at 5 years for those patients left with no residual tumor (81% survival/97% local control), disease confined to the mucosa (83% survival/93% local control), or invasion of the inner half of the myometrium (81% survival/93% local control). However, patients left with deeper myometrial penetration showed a significantly poorer survival rate of 57% (p = 0.02) and a local control rate of only 65% (p = 0.006). For 63 patients treated postoperatively, there was no significant difference in 5-year survival or local control for those patients with disease limited to the inner 1/2 of the myometrium (80% survival/93% local control) compared with more extensive myometrial invasion (75% survival/86% local control). As patients with deep myometrial penetration irradiated postoperatively showed survival rates comparable to patients with lesser extent of invasion, the adverse prognostic effect of deep penetration appears to have been attenuated by subsequent pelvic irradiation. By contrast, residual deep myometrial invasion remained a significant adverse prognostic indicator for patients treated preoperatively. For this group, further treatment seems necessary and postoperative vaginal brachytherapy and/or adjuvant chemotherapy should be considered.

The significance of local recurrence of carcinoma of the breast.

One hundred twenty-one patients with local or regional recurrence of carcinoma of the breast without evidence of distant metastases were treated with megavoltage radiation therapy. All patients had radical or modified radical mastectomy as their initial treatment. The 10 year survival probability of this group of patients is 26%, with a local control probability of 46%. Within this group of patients with recurrent disease, factors found to be associated with a poorer prognosis include peripheral nodal recurrence, advanced initial disease stage and short disease free interval. Contrary to expectation, patients with recurrence within the mastectomy scar (as opposed to chest wall recurrence wide of the scar) or a history of previous radiotherapy had poorer local control rates (although not statistically significant), without effect upon overall survival. Comprehensive radiation therapy (peripheral lymphatic plus chest wall) enhanced the local control rate for the entire group and the survival probability for patients with isolated chest wall recurrence compared with limited radiation therapy fields. (Five year survival probability: chest wall irradiation only = 27%; chest wall and peripheral lymphatic = 54%). Patients given systemic therapy at the time of local recurrence showed no survival benefit. Aggressive, comprehensive radiation therapy is indicated for locally recurrent breast cancer. More effective systemic therapy is needed, especially for higher risk patients.

Laparotomy staged I and II non-Hodgkin's lymphomas: preliminary results of radiotherapy and adjunctive chemotherapy.

Fifty-three non-Hodgkin's lymphoma patients staged I, IE, II, and IIE after laparotomy, received involved field radiotherapy with or without adjunctive chemotherapy. These cases have been analyzed for survival, disease-free survival, sites of relapse, and subsequent management. For nodular lymphoma patients, the five-year survival figure was 87%. While this represents only modest improvement over survival figures for patients staged I and II by lymphangiography, results for patients with upper torso disease were significantly better. Although there was a definite incidence of relapse, early failures common in the lymphangiogram series, were not seen in this study. Of the total group of 14 patients, 4 relapsed after a minimum complete remission period of 20 months. The five-year survival figure for all presentations of stages I and II diffuse histiocytic lymphoma was 85%. This represents a substantial improvement over the corresponding figure of 36% for patients staged clinically after lymphangiography. The improvement in results is credited to more precise staging of patients with peripheral presentations, the use of adjunctive multiple-agent chemotherapy for abdominal and mediastinal presentations, and more effective treatment for relapse. To date, too few patients with peripheral presentations have been treated to determine the value of adjunctive chemotherapy for nodular or diffuse histiocytic patients.