Role of 10-Gy boost radiation after breast-conserving surgery for stage I–II breast cancer with a 5-mm negative margin

The value of oestrogen receptor, progesterone receptor and keratins 5 and 14 immunohistochemistry in the evaluation of epithelial proliferations at cauterised margins in breast-conserving surgery specimens

In breast conservative surgery, it is sometimes difficult to decide whether the cauterised tissue at the inked margin represents normal / hyperplastic or neoplastic tissue. We retrospectively assessed the value of ER, PR, CK5 and CK14 IHC in clarifying the nature of cauterised tissues at the margins concerning 34 lesions of 23 patients. 27 cases belonged to lesions that could not be adequately classified on the basis of the HE stains. Two thirds of them could be classified as non-neoplastic or neoplastic and two thirds of the remaining could be favourised as neoplastic or non-neoplastic, with 3/27 cases remaining uncertain. All 4 IHC reactions were helpful in classifying the lesions in almost half of the cases. However, 3 or 4 immunostains were supportive of the classification in 19/27. The most useful stains were the keratins, generally demonstrating a matching pattern of cell labelling with CK5 and CK14. ER and PR were somewhat less useful in classifying uncertain lesions. Considering all the 27 questionable lesions, IHC with ER, PR, CK5 and CK14 clarified the lesions at the cauterised margins in 23 cases. Taken all these considerations into account, CK5, CK14, PR and ER IHC may help in distinguishing between cautery damaged neoplastic and non-neoplastic tissues. All four IHC may yield the best support for decision making, but CK5 and/or CK14 may be sufficient in their own. The essential approach is that the results must be interpreted with caution, in the context of the given patient's disease, to avoid misinterpretations.

Long-Term Results of Partial Breast Irradiation After Breast-Conserving Surgery for Early Stage Breast Cancer: A Prospective Phase II Trial in China

Background

Partial breast radiotherapy (PBI) has emerged as an option after breast-conserving surgery for early stage breast cancer patients.

Methods

A total of 55 patients with early stage breast cancer between 2009 and 2013 were enrolled in this single-institutional phase II prospective clinical trial. All patients received adjuvant PBI-IMRT after lumpectomy, with the prescription of 48 Gy in 12 fractions at 4 Gy per fraction, 5 days a week. The primary endpoint was ipsilateral breast tumor recurrence (IBTR), the other endpoints were a regional nodal failure (RNF), distant metastasis (DM) rate, disease-free survival (DFS), and overall survival (OS). These endpoints were used to evaluate clinical outcomes. The cosmetic effects and the late toxicity were assessed according to Harvard standard scale and CTCAE 3.0, respectively.

Results

In our cohorts, the median age was 45.60 years old (range 31-65 years) and 29.09% of these patients were post-menopause (n = 16). Most patients were T1 stage (65.45%) or N0 stage (70.91%). 80% of patients were ER-positive, 67.27% PR positive, and 61.82% HER2 negative. At the median follow-up of 9.25 years, RNF was 0% and IBTR occurred in only one patient (1.82%) to the chest wall. Except for one patient (1.82%) had DM to lung and pleura and died from disease progression, the remaining patients were alive at the end of the 10-year follow-up. The 10-year DFS and OS were 94.55 and 98.18%. One patient (1.82%) was diagnosed with endometrial cancer after PBI. Except for 9 patients who declined the cosmetic assessment, the rest of the 46 patients (83.64%) were all rated as good and well-satisfied with the appearance of the irradiated breast. No breast retraction and fibrosis were observed in any of the patients. Additionally, only 4 patients experienced grade 1 late toxicity (7.28%). None had grade 3 or higher late toxicity.

Conclusion

This is the first study to report the 10-year results of PBI after breast-conserving surgery in Chinese patients. Our study suggested that PBI had durable local control and maintained good cosmetic outcomes with minimal late toxicity at long term follow up for the early stage breast cancer patients.

Effects of online cone-beam computed tomography with active breath control in determining planning target volume during accelerated partial breast irradiation

PURPOSE

To test if active breath control during cone-beam computed tomography (CBCT) could improve planning target volume during accelerated partial breast radiotherapy for breast cancer.

METHODS

Patients who were more than 40 years old, underwent breast-conserving dissection and planned for accelerated partial breast irradiation, and with postoperative staging limited to T1-2 N0 M0, or postoperative staging T2 lesion no larger than 3cm with a negative surgical margin greater than 2mm were enrolled. Patients with lobular carcinoma or extensive ductal carcinoma in situ were excluded. CBCT images were obtained pre-correction, post-correction and post-treatment. Set-up errors were recorded at left-right, anterior-posterior and superior-inferior directions. The differences between these CBCT images, as well as calculated radiation doses, were compared between patients with active breath control or free breathing.

RESULTS

Forty patients were enrolled, among them 25 had active breath control. A total of 836 CBCT images were obtained for analysis. CBCT significantly reduced planning target volume. However, active breath control did not show significant benefit in decreasing planning target volume margin and the doses of organ-at-risk when compared to free breathing.

CONCLUSION

CBCT, but not active breath control, could reduce planning target volume during accelerated partial breast irradiation.