Abstract P1-15-09: Ductal Carcinoma In Situ of the Breast: Clinico-Pathological Features Predicting Residual Disease in Postlumpectomy Re-Excision Specimens
Authors: Drinka E , Albuquerque K , Godellas C , Mehta V , Ersahin C , Sinacore J , Albain K , Rajan P. 
Published: April 2011

INTRODUCTION:

Ductal carcinoma in situ (DCIS) is a non-invasive breast cancer, which often grows discontinuously within the breast tissue. Younger age, residual mammographic microcalcifications, positive surgical margins, tumor size, nuclear grade and architectural type are consistently related to ipsilateral breast tumor recurrence in DCIS. To re-excise or not when a lumpectomy margin is close is a controversial issue for breast pathologists, surgeons and oncologists, and often no residual disease is found when a re-excision is performed. The aim of this study is to investigate the clinico-pathological features of DCIS that might predict residual disease in the re-excision specimen in patients treated by lumpectomy with either positive or close margins. METHODS:

Consecutive patients with DCIS who required postlumpectomy re-excision either for positive or for close margins were selected in this retrospective analysis. Close margin was defined as less than 0.1 cm. The initial lumpectomy specimens were examined for tumor size, architectural type, nuclear grade and margin status, and patient age was considered. The subsequent re-excision specimens were analyzed for residual disease. The clinico-pathological features of original lumpectomy specimens were correlated with the presence or absence of residual DCIS in the re-excision specimens. Logistic regression statistical test was used to determine if any of these clinico-pathological features predicted the presence or absence of DCIS in the subsequent re-excision specimens. RESULTS:

There were 37 cases of DCIS without accompanying invasive carcinoma that had positive or close resection margins (positive margin n=8; 21.6%, close margin n=29; 78.4%). Age of the patients ranged from 30 to 93 years. DCIS present in the original lumpectomy specimen was comedo type with necrosis n=8; 21.6% and non-comedo type n-29; 78.4%. Twenty-one lumpectomy specimens (57%) exhibited more than one type of DCIS. Four tumors were nuclear grade 1 (10.8%). 17 were nuclear grade 2 (45.9%), and 16 were nuclear grade 3 (43.2%). Residual DCIS was present in 20 out of 37 (54.1%) re-excision specimens. Six out of 8 (75%) comedo DCIS had residual disease, compared to 14 out of 29 (48.3%) non-comedo DCIS. Eleven out of 20 patients (55%) with residual disease were younger than 60 years. The correlation of patient age and type of DCIS to residual disease in the re-excision specimens was short of statistical significance due to small size of study sample (p value = 0.178 and 0.175 respectively). There was no statistically significant association between nuclear grade and distance to margin with residual disease in re-excision specimens (p value = 0.757 and 0.734 respectively). CONCLUSION:

Younger age and comedo type DCIS may be important factors in predicting residual disease in the re-excision specimens. If this can be confirmed in a larger, multi-institutional data set, there could be a more tailored selection of who needs a re-excision.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-15-09.