Post-mastectomy radiation therapy in breast reconstruction: a patterns of care study of the Korean Radiation Oncology Group

Purpose@#The details of breast reconstruction and radiation therapy (RT) vary between institutions; therefore, we sought to investigate the practice patterns of radiation oncologists who specialize in breast cancer. @*Materials and Methods@#We identified the practice patterns and inter-hospital variations from a multi-center cohort of women with breast cancer who underwent post-mastectomy RT (PMRT) to the reconstructed breast at 16 institutions between 2015 and 2016. The institutions were requested to contour the target volume and produce RT plans for one representative case with five different clinical scenarios and answer questionnaires which elicited infrastructural information. We assessed the inter-institutional variations in RT in terms of the target, normal organ delineation, and dose-volume histograms. @*Results@#Three hundred fourteen patients were included; 99% of them underwent immediate reconstruction. The most irradiated material was tissue expander (36.9%) followed by transverse rectus abdominis musculocutaneous flap (23.9%) and silicone implant (12.1%). In prosthetic-based reconstruction with tissue expander, most patients received PMRT following partial deflation. Conventional fractionation and hypofractionation RT were used in 66.6% and 33.4% patients, respectively (commonest: 40.05 Gy in 15 fractions [17.5%]). Furthermore, 15.6% of the patients received boost RT and 53.5% were treated with bolus. Overall, 15 physicians responded to the questionnaires and six submitted their contours and RT plans. There was a significant variability in target delineations and RT plans between physicians, and between clinical scenarios. @*Conclusion@#Adjuvant RT following post-mastectomy reconstruction has become a common practice in Korea. The details vary significantly between institutions, which highlights an urgent need for standard protocol in this clinical setting.

Post-mastectomy radiation therapy in breast reconstruction: a patterns of care study of the Korean Radiation Oncology Group

Purpose@#The details of breast reconstruction and radiation therapy (RT) vary between institutions; therefore, we sought to investigate the practice patterns of radiation oncologists who specialize in breast cancer. @*Materials and Methods@#We identified the practice patterns and inter-hospital variations from a multi-center cohort of women with breast cancer who underwent post-mastectomy RT (PMRT) to the reconstructed breast at 16 institutions between 2015 and 2016. The institutions were requested to contour the target volume and produce RT plans for one representative case with five different clinical scenarios and answer questionnaires which elicited infrastructural information. We assessed the inter-institutional variations in RT in terms of the target, normal organ delineation, and dose-volume histograms. @*Results@#Three hundred fourteen patients were included; 99% of them underwent immediate reconstruction. The most irradiated material was tissue expander (36.9%) followed by transverse rectus abdominis musculocutaneous flap (23.9%) and silicone implant (12.1%). In prosthetic-based reconstruction with tissue expander, most patients received PMRT following partial deflation. Conventional fractionation and hypofractionation RT were used in 66.6% and 33.4% patients, respectively (commonest: 40.05 Gy in 15 fractions [17.5%]). Furthermore, 15.6% of the patients received boost RT and 53.5% were treated with bolus. Overall, 15 physicians responded to the questionnaires and six submitted their contours and RT plans. There was a significant variability in target delineations and RT plans between physicians, and between clinical scenarios. @*Conclusion@#Adjuvant RT following post-mastectomy reconstruction has become a common practice in Korea. The details vary significantly between institutions, which highlights an urgent need for standard protocol in this clinical setting.

The Effect of Hospital Case Volume on Clinical Outcomes in Patients with Nasopharyngeal Carcinoma: A Multi-institutional Retrospective Analysis (KROG-1106) / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study was to investigate the effect of hospital case volume on clinical outcomes in patients with nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: Data on 1,073 patients with cT1-4N0-3M0 NPC were collected from a multi-institutional retrospective database (KROG 11-06). All patients received definitive radiotherapy (RT) either with three-dimensional-conformal RT (3D-CRT) (n=576) or intensity-modulated RT (IMRT) (n=497). The patients were divided into two groups treated at high volume institution (HVI) (n=750) and low volume institution (LVI) (n=323), defined as patient volume ≥ 10 (median, 13; range, 10 to 18) and < 10 patients per year (median, 3; range, 2 to 6), respectively. Endpoints were overall survival (OS) and loco-regional progression-free survival (LRPFS). RESULTS: At a median follow-up of 56.7 months, the outcomes were significantly better in those treated at HVI than at LVI. For the 614 patients of propensity score-matched cohort, 5-year OS and LRPFS were consistently higher in the HVI group than in the LVI group (OS: 78.4% vs. 62.7%, p < 0.001; LRPFS: 86.2% vs. 65.8%, p < 0.001, respectively). According to RT modality, significant difference in 5-year OS was observed in patients receiving 3D-CRT (78.7% for HVI vs. 58.9% for LVI, p < 0.001) and not in those receiving IMRT (77.3% for HVI vs. 75.5% for LVI, p=0.170). CONCLUSION: A significant relationship was observed between HVI and LVI for the clinical outcomes of patients with NPC. However, the difference in outcome becomes insignificant in the IMRT era, probably due to the standardization of practice by education.

Clinical outcome of proton therapy for patients with chordomas

PURPOSE: To investigate the clinical outcome of proton therapy (PT) in patients with chordoma. MATERIALS AND METHODS: Fifty-eight patients with chordoma treated with PT between June 2007 and December 2015 at the National Cancer Center, Korea, were retrospectively analyzed. The median total dose was 69.6 cobalt gray equivalent (CGE; range, 64.8 to 79.2 CGE). Local progression-free survival (LPFS), distant metastasis-free survival (DMFS), overall survival (OS), and diseasespecific survival (DSS) rates were calculated by the Kaplan–Meier method. RESULTS: With the median follow-up of 42.8 months (range, 4 to 174 months), the 5-year LPFS, DMFS, OS, and DSS rates were 87.9%, 86.7%, 88.3%, and 92.9%, respectively. The tumor location was associated with the patterns of failure: the LPFS rates were lower for cervical tumors (57.1%) than for non-cervical tumors (93.1%) (p = 0.02), and the DMFS rates were lower for sacral tumors (53.5%) than for non-sacral tumors (100%) (p = 0.001). The total dose was associated with both the LPFS rate and DMFS rate. The initial tumor size was associated with the DMFS rate, but was not associated with the LPFS rate. Three patients had grade 3 late toxicity with none ≥grade 4. CONCLUSION: PT is an effective and safe treatment in patients with chordomas. The tumor location was associated with the patterns of failure: local failure was common in cervical tumors, and distant failure was common in sacral tumors. Further refinement of PT, such as the utilization of intensity modulated PT for cervical tumors, is warranted to improve the outcome.

Postmastectomy Radiotherapy in Patients with pT1-2N1 Breast Cancer Treated with Taxane-Based Chemotherapy: A Retrospective Multicenter Analysis (KROG 1418) / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study was to evaluate the impact of postmastectomy radiotherapy (PMRT) on loco-regional recurrence-free survival (LRRFS), disease-free survival (DFS), and overall survival (OS) in pT1-2N1 patients treated with taxane-based chemotherapy. MATERIALS AND METHODS: We retrospectively reviewed the medical data of pathological N1 patients who were treated with modified radical mastectomy and adjuvant taxane-based chemotherapy in 12 hospitals between January 2006 and December 2010. RESULTS: We identified 714 consecutive patients. The median follow-up duration was 69 months (range, 1 to 114 months) and the 5-year LRRFS, DFS, and OS rates were 97%, 94%, and 98%, respectively, in patients who received PMRT (PMRT [+]). The corresponding figures were 96%, 90%, and 96%, respectively, in patients who did not receive PMRT (PMRT [–]). PMRT had no significant impact on survival. Upon multivariable analysis, only the histological grade (HG) was statistically significant as a prognostic factor for LRRFS and DFS. In a subgroup analysis of HG 3 patients, PMRT (+) showed better DFS (p=0.081). CONCLUSION: PMRT had no significant impact on LRRFS, DFS, or OS in pT1-2N1 patients treated with taxane-based chemotherapy. PMRT showed a marginal benefit for DFS in HG 3 patients. Randomized studies are needed to confirm the benefit of PMRT in high risk patients, such as those with HG 3.

Neurocognitive and Psychological Functioning of Children with an Intracranial Germ Cell Tumor / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This study was conducted to investigate the neurocognitive functioning of children with intracranial germ cell tumor (IGCT) prior to receiving proton beam therapy (PBT), and to identify differential characteristics of their neurocognitive functioning depending on tumor location. As a secondary object of this study, neurocognitive functions were followed up at 1-2 years after PBT to examine early post-treatment changes. MATERIALS AND METHODS: Between 2008 and 2014, 34 childrenwith IGCT treatedwho received PBT atNational Cancer Center, Korea were enrolled in this study. Standardized neurocognitive tests of intelligence, memory, and executive functioning were performed with baseline psychological assessments using the Child Behavior Checklist (CBCL). Follow-up assessments after PBT were conducted in 20 patients (T2). The results were analyzed based on the locations of tumors, which included the suprasellar, pineal gland, basal ganglia, and bifocal regions. RESULTS: The neurocognitive function of IGCT patients was significantly lower than that of the normal population in performance intelligence quotient (p=0.041), processing speed (p=0.007), memory (p < 0.001), and executive functioning (p=0.010). Patients with basal ganglia tumors had significantly lower scores for most domains of neurocognitive functioning and higher scores for CBCL than both the normal population and patients with IGCT in other locations. There was no significant change in neurocognitive function between T1 and T2 for all types of IGCT patients in first 1-2 years after PBT. CONCLUSION: Tumor location significantly affects the neuropsychological functioning in patients with IGCT. Neuropsychological functioning should be closely monitored from the time of diagnosis in IGCT patients.

Effects of Postoperative Radiotherapy on Leptomeningeal Carcinomatosis or Dural Metastasis after Resection of Brain Metastases in Breast Cancer Patients / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: In this retrospective study, we compared the incidence of leptomeningeal carcinomatosis or dural metastasis (LMCDM) in patients who received whole brain radiotherapy (WBRT), partial radiotherapy (PRT), or no radiotherapy (RT) following resection of brain metastases from breast cancer. MATERIALS AND METHODS: Fifty-one patients with breast cancer underwent surgical resection for newly diagnosed brain metastases in two institutions between March 2001 and March 2015. Among these, 34 received postoperative WBRT (n=24) or PRT (n=10) and 17 did not. RESULTS: With a median follow-up of 12.4 months (range, 2.3 to 83.6 months), 22/51 patients developed LMCDM at a median of 8.6 months (range, 4.8 to 51.2 months) after surgery. The 18-months LMCDM-free survival (LMCDM-FS) rates were 77.5%, 30.0%, and 13.6%, in the WBRT, PRT, and no RT groups, respectively (p=0.013). The presence of a tumor adjacent to cerebrospinal fluid flow and no systemic treatment after treatment for brain metastases were also associated with poor LMCDM-FS rate. Multivariate analysis showed that WBRT compared to PRT (p=0.009) and systemic treatment (p < 0.001) were independently associated with reduced incidence of LMCDM. CONCLUSION: WBRT improved LMCDM-FS rate after resection of brain metastases compared to PRT in breast cancer patients.

Effects of Postoperative Radiotherapy on Leptomeningeal Carcinomatosis or Dural Metastasis after Resection of Brain Metastases in Breast Cancer Patients / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: In this retrospective study, we compared the incidence of leptomeningeal carcinomatosis or dural metastasis (LMCDM) in patients who received whole brain radiotherapy (WBRT), partial radiotherapy (PRT), or no radiotherapy (RT) following resection of brain metastases from breast cancer. MATERIALS AND METHODS: Fifty-one patients with breast cancer underwent surgical resection for newly diagnosed brain metastases in two institutions between March 2001 and March 2015. Among these, 34 received postoperative WBRT (n=24) or PRT (n=10) and 17 did not. RESULTS: With a median follow-up of 12.4 months (range, 2.3 to 83.6 months), 22/51 patients developed LMCDM at a median of 8.6 months (range, 4.8 to 51.2 months) after surgery. The 18-months LMCDM-free survival (LMCDM-FS) rates were 77.5%, 30.0%, and 13.6%, in the WBRT, PRT, and no RT groups, respectively (p=0.013). The presence of a tumor adjacent to cerebrospinal fluid flow and no systemic treatment after treatment for brain metastases were also associated with poor LMCDM-FS rate. Multivariate analysis showed that WBRT compared to PRT (p=0.009) and systemic treatment (p < 0.001) were independently associated with reduced incidence of LMCDM. CONCLUSION: WBRT improved LMCDM-FS rate after resection of brain metastases compared to PRT in breast cancer patients.

Treatment outcomes after adjuvant radiotherapy following surgery for patients with stage I endometrial cancer

PURPOSE: The purpose of this study is to evaluate the treatment outcomes of adjuvant radiotherapy using vaginal brachytherapy (VB) with a lower dose per fraction and/or external beam radiotherapy (EBRT) following surgery for patients with stage I endometrial carcinoma. MATERIALS AND METHODS: The subjects were 43 patients with the International Federation of Gynecology and Obstetrics (FIGO) stage I endometrial cancer who underwent adjuvant radiotherapy following surgery between March 2000 and April 2014. Of these, 25 received postoperative VB alone, while 18 received postoperative EBRT to the whole pelvis; 3 of these were treated with EBRT plus VB. The median EBRT dose was 50.0 Gy (45.0–50.4 Gy) and the VB dose was 24 Gy in 6 fractions. Tumor dose was prescribed at a depth of 5 mm from the cylinder surface and delivered twice per week. RESULTS: The median follow-up period for all patients was 57 months (range, 9 to 188 months). Five-year disease-free survival (DFS) and overall survival (OS) for all patients were 92.5% and 95.3%, respectively. Adjuvant radiotherapy was performed according to risk factors and stage IB, grade 3 and lymphovascular invasion were observed more frequently in the EBRT group. Five-year DFS for EBRT and VB alone were 88.1% and 96.0%, respectively (p = 0.42), and 5-year OS for EBRT and VB alone were 94.4% and 96%, respectively (p = 0.38). There was no locoregional recurrence in any patient. Two patients who received EBRT and 1 patient who received VB alone developed distant metastatic disease. Two patients who received EBRT had severe complications, one each of grade 3 gastrointestinal complication and pelvic bone insufficiency fracture. CONCLUSION: Adjuvant radiotherapy achieved high DFS and OS with acceptable toxicity in stage I endometrial cancer. VB (with a lower dose per fraction) may be a viable option for selected patients with early-stage endometrial cancer following surgery.

Long-term results of forward intensity-modulated radiation therapy for patients with early-stage breast cancer

PURPOSE: To observe long-term clinical outcomes for patients with early-stage breast cancer treated with forward intensity-modulated radiation therapy (IMRT), including local control and clinical toxicities. MATERIALS AND METHODS: We retrospectively analyzed a total of 214 patients with stage I-II breast cancer who were treated with breast conserving surgery followed by adjuvant breast radiation therapy between 2001 and 2008. All patients were treated using forward IMRT. The whole breast was irradiated to a dose of 50 to 50.4 Gy followed by an 8 to 12 Gy electron boost to the surgical bed. RESULTS: The median age was 46 years (range, 21 to 82 years) and the medial follow-up time was 7.3 years (range, 2.4 to 11.7 years). Stage T1 was 139 (65%) and T2 was 75 (35%), respectively. Ipsilateral breast recurrence was observed in 3 patients. The 5- and 10-year local control rates were 99.1% and 97.8%, respectively. The cosmetic outcome was evaluated according to the Harvard scale and 89.4% of patients were scored as excellent or good. CONCLUSION: The whole breast radiation therapy as an adjuvant treatment using a forward IMRT technique showed excellent long-term local control as well as favorable outcomes of toxicity and cosmesis.

Factors predicting radiation pneumonitis in locally advanced non-small cell lung cancer

PURPOSE: Thoracic radiotherapy is a major treatment modality of stage III non-small cell lung cancer. The normal lung tissue is sensitive to radiation and radiation pneumonitis is the most important dose-limiting complication of thoracic radiation therapy. This study was performed to identify the clinical and dosimetric parameters related to the risk of radiation pneumonitis after definitive radiotherapy in stage III non-small cell cancer patients. MATERIALS AND METHODS: The medical records were reviewed for 49 patients who completed definitive radiation therapy for locally advanced non-small cell lung cancer from August 2000 to February 2010. Radiation therapy was delivered with the daily dose of 1.8 Gy to 2.0 Gy and the total radiation dose ranged from 50.0 Gy to 70.2 Gy (median, 61.2 Gy). Elective nodal irradiation was delivered at a dose of 45.0 Gy to 50.0 Gy. Seven patients (14.3%) were treated with radiation therapy alone and forty two patients (85.7%) were treated with chemotherapy either sequentially or concurrently. RESULTS: Twenty-five cases (51.0%) out of 49 cases experienced radiation pneumonitis. According to the radiation pneumonitis grade, 10 (20.4%) were grade 1, 9 (18.4%) were grade 2, 4 (8.2%) were grade 3, and 2 (4.1%) were grade 4. In the univariate analyses, no clinical factors including age, sex, performance status, smoking history, underlying lung disease, tumor location, total radiation dose and chemotherapy were associated with grade > or =2 radiation pneumonitis. In the subgroup analysis of the chemotherapy group, concurrent rather than sequential chemotherapy was significantly related to grade > or =2 radiation pneumonitis comparing sequential chemotherapy. In the univariate analysis with dosimetric factors, mean lung dose (MLD), V20, V30, V40, MLDipsi, V20ipsi, V30ipsi, and V40ipsi were associated with grade > or =2 radiation pneumonitis. In addition, multivariate analysis showed that MLD and V30 were independent predicting factors for grade > or =2 radiation pneumonitis. CONCLUSION: Concurrent chemotherapy, MLD and V30 were statistically significant predictors of grade > or =2 radiation pneumonitis in patients with stage III non-small cell lung cancer undergoing definitive radiotherapy. The cutoff values for MLD and V30 were 16 Gy and 18%, respectively.

Setting Up a CR Based Filmless Environment for the Radiation Oncology / 의학물리

The analog image based system consisted of a simulator and medical linear accelerator (LINAC) for radiotherapy was upgraded to digital medical image based system by exchanging the X-ray film with Computed Radiography (CR). With minimum equipments shift and similar treatment process, it was possible that the new digital image system was adapted by the users in short time. The film cassette and the film developer device were substituted with a CR cassette and a CR Reader, where the ViewBox was replaced with a small size PC and a monitor. The viewer software suitable for radiotherapy was developed to maximize the benefit of digital image, and as the result the convenience and the effectiveness was improved. It has two windows to display two different images in the same time and equipped various search capability, contouring, window leveling, image resizing, translation, rotation and registration functions. In order to avoid any discontinuance of the treatment while the transition to digital image, the film and the CR was used together for 1 week, and then the film developer was removed. Since then the CR System has been operated stably for 2 months, and the various requests from users have been reflected to improve the system.