Intraoperative Electron Radiotherapy (IOERT) as an Alternative to Standard Whole Breast Irradiation: Only for Low-Risk Subgroups?

BACKGROUND: Intraoperative radiotherapy during breast-conserving surgery is being studied as an alternative to 6 weeks of external beam radiotherapy (EBRT) for low-risk women; it can be delivered using electrons (intraoperative electron radiotherapy, IOERT) or 50-kV X-rays. MATERIALS AND METHODS: We analyzed both single institutional and randomized studies involving single-fraction IOERT treatments. Rates for ipsilateral breast tumor recurrences, disease-specific survival, and overall survival were obtained. RESULTS: IOERT had true 5-year recurrence rates of > 1.5% for ASTRO (American Society for Radiation Oncology) and ESTRO (European Society for Therapeutic Radiology and Oncology) suitable women, or for low-risk women as defined by the ELIOT trial. Women with ductal carcinoma in situ eligible for breast-conserving therapy, older women that currently receive no EBRT, and younger women with favorable biology are additional potential candidates. CONCLUSION: ASTRO suitable and ESTRO good women for accelerated partial breast irradiation are low-risk groups. Higher-risk women with favorable biology might also be suitable candidates for IOERT, providing the tumor biology can be determined prior to surgery. For intraoperative radiotherapy using 50-kV X-rays, follow-up was too short to assess the effectiveness of the treatment.

Accelerated partial breast irradiation using only intraoperative electron radiation therapy in early stage breast cancer.

BACKGROUND: We report the results of a single-institution, phase II trial of accelerated partial breast irradiation (APBI) using a single dose of intraoperative electron radiation therapy (IOERT) in patients with low-risk early stage breast cancer. METHODS AND MATERIALS: A cohort of 226 patients with low-risk, early stage breast cancer were treated with local excision and axillary management (sentinel node biopsy with or without axillary node dissection). After the surgeon temporarily reapproximated the excision cavity, a dose of 21 Gy using IOERT was delivered to the tumor bed, with a margin of 2 cm laterally. RESULTS: With a mean follow-up of 46 months (range, 28-63 months), only 1 case of local recurrence was reported. The observed toxicity was considered acceptable. CONCLUSIONS: APBI using a single dose of IOERT can be delivered safely in women with early, low-risk breast cancer in carefully selected patients. A longer follow-up is needed to ascertain its efficacy compared to that of the current standard treatment of whole-breast irradiation.

Regional hyperthermia added to intensified preoperative chemo-radiation in locally advanced adenocarcinoma of middle and lower rectum.

PURPOSE: To evaluate the safety of delivering pre-operative regional hyperthermia (HT) plus an intensified chemo-radiotherapy (CRT) regimen in patients suffering from locally advanced rectal cancer. METHODS: Between June 2000 and April 2006, 76 patients with locally advanced (cT3-4 N0/+) rectal adenocarcinoma were treated with HT plus CRT. HT was given once a week, to a total of five treatments, 1 to 4 h after radiotherapy (50 Gy with 2-Gy fractions for 5 weeks, plus a 10-Gy boost on the tumour bed, with the same fractionation schedule). Chemotherapy consisted in 5FU 200 mg/m(2) continuous infusion throughout the 6 weeks of irradiation and OXA 45 mg/m(2) in a weekly bolus. Surgery followed 4 to 6 weeks after the completion of HT plus CRT. RESULTS: HT plus CRT was generally well tolerated. At pathologic examination, there was a pathologic complete response (pCR) (ypT0 ypN0) in 18 out of 76 patients (23.6%), a partial response (PR) in 34/76 ones (44.7%) and a stable disease (SD) in 20/76 (26.3%) ones; 4/76 patients (5.2%) had a progression disease (PD) (distant metastases) at the time of surgery. Good predictors of a longer disease-free survival (DFS) were in order ypN status (log-rank test: p = 0.0008), ypT status (p = 0.002) and pCR (p = 0.03). CONCLUSION: Preoperative CRT combined with regional HT yielded acceptable toxicity. The rate of pCR was encouraging, although further studies are needed to prove the long-term efficacy of adding HT to CRT.