Post-operative radiotherapy for ductal carcinoma in situ of the breast

Accelerated partial breast irradiation compared with whole breast radiation therapy: a breast cancer cohort study measuring change in radiation side-effects severity and quality of life

PURPOSE

Radiotherapy (RT) after breast-conserving surgery for early-stage breast cancer patients has similar survival benefits with whole breast RT (WBRT) or accelerated partial breast irradiation (APBI). However, the impact of RT type and side-effects severity on change in quality of life (QOL) is unknown. We examined changes in RT side-effects severity and QOL by RT type.

METHODS

We analyzed data from a cohort of 285 newly diagnosed early-stage breast cancer patients with tumor size ≤3.0 cm and lymph node-negative disease. Patients (93 [32.6%] stage 0; 49 [17.2%] non-white; mean age = 59.3 years) completed four interviews (6 weeks, 6, 12, and 24 months) after definitive surgical treatment. We measured severity of RT side effects, fatigue and skin irritation, using a 5-point scale (1 "not at all" to 5 "all the time") and measured QOL using the Functional Assessment of Cancer Therapy-Breast (FACT-B) and RAND 36-item Health Survey Vitality subscale. Repeated-measures analysis of covariance of each outcome controlled for demographic, clinical/treatment, and psychosocial factors.

RESULTS

Patients initiated RT by 6 months (113 received APBI; 172 received WBRT) and completed RT by 12 months. Patients receiving WBRT (vs. APBI) reported greater increase in fatigue and skin irritation severity from 6-week to 6-month interviews (each P < 0.001). Improvement in neither total FACT-B nor Vitality differed significantly by RT type over 2-year follow-up.

CONCLUSIONS

Findings suggest that early-stage breast cancer patients can benefit from less-severe, short-term side effects of APBI with no differential impact on QOL change within 2-year follow-up.

Ductal carcinoma in situ: recent advances and future prospects

Introduction. This article reviews current management strategies for DCIS in the context of recent randomised trials, including the role of sentinel lymph node biopsy (SLNB), adjuvant radiotherapy (RT) and endocrine treatment. Methods. Literature review facilitated by Medline, PubMed, Embase and Cochrane databases. Results. DCIS should be managed in the context of a multidisciplinary team. Local control depends upon clear surgical margins (at least 2 mm is generally acceptable). SLNB is not routine, but can be considered in patients undergoing mastectomy (Mx) with risk factors for occult invasion. RT following BCS significantly reduces local recurrence (LR), particularly in those at high-risk. There remains a lack of level-1 evidence supporting omission of adjuvant RT in selected low-risk cases. Large, multi-centric or recurrent lesions should be treated by Mx and immediate reconstruction should be discussed. Adjuvant hormonal treatment may reduce the risk of LR in selected cases with hormone sensitive disease. Conclusion. Further research is required to determine the role of new RT regimes and endocrine therapies. Biological profiling and molecular analysis represent an opportunity to improve our understanding of tumour biology in DCIS to rationalise treatment. Reliable identification of low-risk lesions could allow treatment to be less radical.

Prevalence of BRCA1 and BRCA2 mutations in women with breast carcinoma In Situ and referred for genetic testing

Ductal and lobular carcinoma in situ (CIS) accounted for 62,280 (24.5%) of all new breast cancer diagnoses in 2009. BRCA1/2 mutations confer an extremely high risk of breast cancer, and management guidelines for BRCA1/2 mutation carriers advise close follow-up, intensive screening, and consideration of prophylactic surgery to lower this risk. The limited relevant previous data are not definitive in establishing the prevalence of BRCA1/2 mutations in breast CIS patients, creating uncertainty as to whether referral for cancer risk assessment and genetic testing is appropriate for this group. Therefore, we conducted a cross-sectional analysis of the Myriad Genetics BRCA1/2 database to determine the prevalence of these mutations in breast CIS patients. All statistical tests were 2-sided, and confidence intervals (CI) are reported at the 95% level (α = 0.05). The source population was 64,717 consecutive women who were not Ashkenazi Jewish, underwent BRCA1/2 testing, and provided a personal and family history of invasive breast and ovarian cancer; 7,295 (11.3%) reported a diagnosis of CIS (ductal or lobular) and had an overall 5.9% prevalence of mutated BRCA1/2 (mBRCA). Subgrouped by history (personal or family) of invasive breast and/or ovarian cancer, these CIS patients had the following prevalences of mBRCA: (1) no personal or family history, 2.3%; (2) personal history, 5.2%; (3) family history, 5%; and (4) personal and family history, 10.3%. mBRCA risk was significantly higher in women with early-onset (<50 years old) CIS than with late-onset (≥ 50 years old) CIS [odds ratio (OR) = 1.5; 95% CI = 1.1-2.1). Disease onset at less than 40 years age was associated with an even higher mBRCA risk (OR = 1.8; 95% CI = 1.3-2.3). By far the largest analysis of BRCA1/2 mutation prevalence in non-Ashkenazi Jewish breast CIS patients, this study shows that early-onset CIS is associated with mBRCA1/2 in patients referred for genetic testing. When a family history of breast and/or ovarian cancer are also present, testing women with early-onset CIS may increase both the likelihood of detecting BRCA1/2 mutations and opportunities for carriers to consider additional cancer prevention strategies.