Pleomorphic Lobular Carcinoma In Situ: Radiologic–Pathologic Features and Clinical Management

Abstract

Background Pleomorphic lobular carcinoma in situ (PLCIS) is an unusual variant of LCIS for which optimal management remains unclear. Methods We conducted a 15-year (2000–2014) retrospective chart review of the radiologic, pathologic, clinical management, and recurrence rates of patients with PLCIS on diagnostic biopsy. Fifty-one patients were found to have PLCIS either alone or with concomitant breast cancer. Of these, 23 were found to have pure PLCIS on diagnostic biopsy. Rates of upstaging after local excision, positive or close margins, mastectomy, and recurrence associated with pure pleomorphic lobular carcinoma in situ were examined. Results Of the 21 patients who underwent surgical excision following diagnostic biopsy, 33.3 % (7/21) were found to have invasive carcinoma, and 19 % (4/23) were found to have ductal carcinoma in situ. Extensive or multifocal PLCIS was present in 47.6 % (10/21) of patients, corresponding to at least one PLCIS-positive or close margin in 71.4 % (15/21). In total, there were 11 local reexcisions in nine patients, and 12 mastectomies. No ipsilateral breast cancer events have occurred, including in those with positive or close surgical margins (mean followup 4.1 years). Conclusions Patients with isolated PLCIS on diagnostic biopsy are at high risk of upgrading to invasive cancer or ductal carcinoma in situ at diagnostic excision. PLCIS often is extensive, with high rates of positive or close surgical resection margins. If negative PLCIS margins are pursued, rates of successful breast conservation are low. In light of this and low recurrence rates, caution should be exercised in aggressively treating PLCIS with excision to clear margins.

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

“…This is the position of the National Cancer Comprehensive Network (NCCN) and NHS breast screening program (NHSBSP) who recommend treating PLCIS similar to DCIS (29,30). However, as evident in more recent studies, such an approach may not be consistent with breast conservation (28). This clinical issue warrants investigation in appropriately powered, well-designed, prospective studies for a satisfactory resolution of all concerns.…”

“…The most recent study to comment on recurrence rates was that of Flanagan et al (28) who reported on a case series of 23 patients who were diagnosed with PLCIS. Of these 23 patients, 2 had adequate margins on the excisional biopsy and required no further intervention, while 16 underwent wide local excision and 5 had mastectomies.…”

“…However, they also emphasize that the pursuit of clear margins in the case of PLCIS precluded successful breast conservation. Therefore, the authors urge caution in the aggressive treatment of PLCIS with regards to margins (28). …”

“…All of the authors appear to agree that clear margins will lead to lower recurrence rates. However, Flanagan et al (28) report that this may not always be possible or feasible.…”

Diagnosis and Treatment of Breast Cancer in Situ. Russian Association of Oncological Mammology Clinical Guidelines (Project)

“…Однако убе-дительных достоверных доказательств, что позитивные края при плеоморфном варианте LCIS существенно увеличивают риск рецидива, пока явно недостаточно. В отличие от классического варианта LCIS при плео-морфном варианте необходимо выполнять оперативное вмешательство (по крайней мере эксцизионную биоп-сию), так как более чем в 50 % (0-65 %) случаев в об-ласти первичной биопсии обнаруживается DCIS или инвазивный рак, которые и будут определять про-гноз заболевания [26]. При этом примерно в половине случаев приходится проводить мастэктомию, так как при таком варианте рака in situ сложно, а иногда и невозможно достичь негативных хирургических кра-ев из-за диффузного роста опухоли и мультифокально-сти (в том числе в виде очагов инвазивного рака).…”