Correlation between C-MYC and HER2 Amplification in Non-selected Breast Cancers / 한국유방암학회지

PURPOSE: c-myc and HER2 have been reported be amplified in 20% to 30% of clinical breast cancers and appears to be related with poor clinical outcome. The relationship between amplification of c-myc and HER2 and other clinical and biological characteristics of the breast cancers, including clinical outcome, are described. METHODS: c-myc and HER2 amplification were analyzed on 225 consecutive non-selected breast cancers by fluorescence in situ hybridization using tissue microarray technology. RESULTS: c-myc was amplified in 33 cases (15.4%) and HER2 was amplified in 49 cases (23.3%). c-myc amplification was significantly increased with HER2 amplification (p<0.001) and closely linked with cell proliferative activity measured by Ki67 labeling index (p=0.010). In univariate survival analysis, lymph node status, tumor size, and histologic grade of the tumors were significant prognostic factors. However, lymph node status was the only significant prognostic factor for predicting patient survival in multivariate analysis. Patient survival was not different according to c-myc amplification status and c-myc amplification showed no significant correlation with clinco-pathologic parameters of the tumors. CONCLUSION: A strong correlation between c-myc and HER2 amplifications, and cell proliferative activity indicate a biologic link between c-myc and HER2 in breast cancer.

Partial Breast Irradiation Using Brachy-therapy after Breast Conserving Surgery / 한국유방암학회지

PURPOSE: Whole breast irradiation (WBI) after breast conserving surgery (BCS) is the standard treatment modality for controlling ipsilateral local recurrence of breast cancer. However, the WBI needs 5 to 6 weeks of the treatment period. Partial breast irradiation (PBI) has recently appeared as an alternative treatment to WBI in selected early breast cancer patients. This study was performed to evaluate the feasibility of PBI alone after BCS. METHODS: The brachy-catheters were inserted at the lumpectomy site after BCS. Six to nine days after the operation, the patients underwent fractionated PBI twice in a day with median dose of 3 Gy. The median value of the total dose was 3,120 cGy (28 to 34 Gy) given over 5 days. Forty-one patients who were proven as having a tumor-free margin by pathologic report were included in this study. Thirty-five patients had axillary lymph node-negative disease and thirty- six patients underwent concurrent adjuvant CMF chemotherapy. Follow-up ultrasono graphy was performed one month after the completion of PBI. RESULTS: The median post-operative hospital stay was 15 days (range: 12-17 days). Twenty-eight patients had seromas smaller than 1 cm in size and the 13 patients appeared to have 1~3 cm sized seromas on the follow-up ultrasonography. Long lasting (> 3 months) seromas were observed in 7 patients. None of the patients complained of tenderness or discomfort of the operation site and complications such as skin desquamation, pigmentation and wound contracture were not observed. Fat necrosis was observed in 1 patient. There was no case of local recurrence at the median follow-up period of 19 months (range: 15-41 months). CONCLUSION: PBI for early breast cancer using interstitial brachytherapy was a safe and effective alternative to WBI with excellent cosmetic results after BCS. The results of the current study prompts a multi-center clinical trial of PBI as an alternative to the WBI in early breast cancer to validate its feasibility in a selected patient population.

Feasibility of Concurrent Adjuvant Chemotherapy and Radiotherapy after Breast-conserving Surgery in Early Breast Cancer / 한국유방암학회지

PURPOSE: The optimal sequence of chemotherapy (CT) and radiotherapy (RT) remains uncertain although both can reduce breast cancer recurrence after breast-conserving surgery (BCS). The current study was performed to evaluate whether concurrent RT with CT increases chemotherapy-associated toxicities. METHODS: Two hundred and thirty-eight patients with stage I and II breast cancers were prospectively allocated concurrent CT and RT (N=133) or sequential CT and RT (N= 105) after BCS. In the sequential group, the RT was started after completion of 3 cycles of CT with an additional 3 cycles of CT delivered after the RT. All patients underwent intravenous CMF chemotherapy composed of cyclophosphamide (500 mg/m2), methotrexate (50 mg/m2) and 5-FU (500 mg/ m2), every 3 weeks for 6 cycles following surgery. RESULTS: There were no significant differences between the two groups with regard to the grade 3 or 4 hematologic toxicities during chemotherapy or in abnormal liver enzyme elevation. Radiation related adverse effects, such as moist desquamation and pneumonitis symptom, were no different between the two groups. During the median 42 month follow-up period, range 16- to 60 months, 18 (13.5%) and 20 (19.1%) patients in the concurrent and sequential groups had systemic recurrences of breast cancer. The disease-free survival and local recurrence rates were no different between the two groups. CONCLUSION: Concurrent CT and RT were not associated with an increased toxicity and reasonable cosmetic results were achieved in this current study. The current study indicates that concurrent RT with CT after BCS is a feasible treatment modality, with the advantage of a shortening treatment time.