Role of boost radiotherapy for local control of pure ductal carcinoma in situ after breast-conserving surgery: a multicenter, retrospective study of 622 patients.

PURPOSE: To evaluate the effect of boost radiotherapy on ipsilateral breast tumor recurrence (IBTR) for ductal carcinoma in situ (DCIS) after breast-conserving surgery and whole breast radiotherapy (WBRT) with or without boost. METHODS AND MATERIALS: Retrospective, multicentre study of 622 patients (624 tumors) diagnosed with pure DCIS from 1993-2011. RESULTS: Most tumors (377/624; 60.4%) received a boost. At a median follow-up of 8.8 years, IBTR occurred in 64 cases (10.3%). A higher percentage of patients with risk factors for IBTR received a boost (p < 0.05). Boost was not associated with lower rates of IBTR than WBRT alone (HR 0.75, 95% CI 0.42-1.35). On the univariate analyses, IBTR was significantly associated with tumor size (11-20 mm, HR 2.32, 95% CI 1.27-4.24; and > 20 mm, HR 2.10, 95% CI 1.14-3.88), re-excision (HR 1.76, 95% CI 1.04-2.96), and tamoxifen (HR 2.03, 95% CI 1.12-3.70). Boost dose > 16 Gy had a protective effect (HR 0.39, 95% CI 0.187-0.824). Multivariate analyses confirmed the independent associations between IBTR and 11-20 mm (p = 0.02) and > 20 mm (p = 0.009) tumours, and re-excision (p = 0.006). On the margin-stratified multivariate analysis, tamoxifen was a poor prognostic factor in the close/positive margin subgroup (HR 4.28 95% CI 1.23-14.88), while the highest boost dose ( > 16 Gy) had a significant positive effect (HR 0.34, 95% CI 0.13-0.86) in the negative margin subgroup. CONCLUSIONS: Radiotherapy boost did not improve the risk of IBTR. Boost radiotherapy was more common in patients with high-risk disease. Tumor size and re-excision were significant independent prognostic factors.

Detection of incident breast and colorectal cancer cases from an administrative healthcare database in Catalonia, Spain.

OBJECTIVE: To validate the Catalan minimum basic data set (MBDS) of hospital discharges as an information source for detecting incident breast (BC) and colorectal cancer (CRC), against the Hospital del Mar Cancer Registry (RTHMar) in Barcelona (Spain) as the gold standard. METHODS: Using ASEDAT software (Analysis, Selection and Extraction of Tumour Data), we identified Catalan public hospital discharge abstracts in patients with a first-time diagnosis of BC and CRC in the years 2005, 2008, and 2011, aggregated by unique patient identifiers and sorted by date. Once merged with the RTHMar database and anonymized, tumour-specific algorithms were validated to extract data on incident cases, tumour stage, surgical treatment, and date of incidence. RESULTS: MBDS had a respective sensitivity and positive predictive value (PPV) of 78.0% (564/723) and 90.5% (564/623) for BC case detection; and 83.9% (387/461) and 94.9% (387/408) for CRC case detection. The staging algorithms overestimated the proportion of local-stage cases and underestimated the regional-stage cases in both cancers. When loco-regional stage and surgery were combined, sensitivity and PPV reached 98.3% and 99.8%, respectively, for BC and 96.4% and 98.4% for CRC. The differences between dates of incidence between RTHMar and MBDS were greater for BC cases without initial surgery, whereas they were generally smaller and homogeneous for CRC cases. CONCLUSIONS: The MBDS is a valid and efficient instrument to improve the completeness of a hospital-based cancer registry (HBCR), particularly in BC and CRC, which require hospitalization and are predominantly surgical.

Reoperations after primary breast conserving surgery in women with invasive breast cancer in Catalonia, Spain: a retrospective study.

BACKGROUND: Although complete tumor resection is accepted as the best means to reduce recurrence, reoperations after lumpectomy are a common problem in breast cancer. The aim of this study was to assess the reoperation rates after primary breast conserving surgery in invasive breast cancer cases diagnosed in Catalonia, Spain, between 2005 and 2011 and to identify variations based on patient and tumour characteristics. METHODS: Women with invasive incident breast cancer identified from the Patient's Hospital Discharge Database [174.0-174.9 codes of the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) as the primary diagnosis] and receiving primary breast conserving surgery were included in the study and were followed up to 3 and 12 months by collecting information about repeat breast cancer surgery. RESULTS: Reoperation rates after primary breast conserving surgery decreased from 13.0 % in 2005 to 11.7 % in 2011 at 3 months and from 14.2 % in 2005 to 12.9 % in 2011 at 12 months' follow-up. While breast conservation reoperations saw a slight, non-significant increase in the same period (from 5.7 to 7.3 % at 3 months, and from 6.0 to 7.5 % at 12 months), there was a significant decrease in radical reoperation (from 7.3 to 4.4 % at 3 months and from 8.2 to 5.4 % at 12 months). Overall, additional breast surgeries decreased among younger women. CONCLUSIONS: Despite the rise of breast conserving surgery, reoperation rates following initial lumpectomy in Catalonia decreased by 10 % at 3 and 12 months' follow-up, remaining low and almost unchanged. Ultimately, there was also a significant decrease in mastectomies.