Pleomorphic lobular carcinoma in situ: Current evidence and a systemic review

Pleomorphic lobular carcinoma in situ (PLCIS) has only recently been identified as a distinct pathological entity within classic lobular carcinoma in situ (CLCIS). As such, there is currently no consensus among clinicians regarding the optimal treatment of this disease. The present study determined the risk of concomitant invasive disease and ductal carcinoma in situ (DCIS) if PLCIS is observed on core needle biopsy (CNB) and collated the evidence regarding the risk of recurrence in relation to surgical margins and adjuvant therapy. In addition, the pertinent literature available through MedLine, PubMed, the WHO Clinical Trials Registry Platform and Google Scholar using appropriate keywords was reviewed. The pooled results of studies in the literature demonstrated a concomitant presence of invasive disease of 40%, and 15% for DCIS. The studies that examined recurrence rates indicated that the risk is reduced with ample resection margins (>2 mm) and adjuvant radiotherapy. However, recent studies raise concerns regarding breast conservation when pursuing clear margins. No level 1 evidence from prospective studies, randomized controlled trials (RCTs), or meta-analyses based on such RCTs was identified. This is a clinical issue that warrants investigation in appropriately powered well designed prospective studies for a satisfactory resolution of all concerns.