A. Desai1, Y. Tjendra2, B. Susnik2, N. Goel1, S. B. Kesmodel1 1University Of Miami, Department Of Surgery, Miami, FL, USA 2University Of Miami, Department Of Pathology, Miami, FL, USA
Introduction: Florid lobular carcinoma in situ (FLCIS) is an uncommon lobular neoplasia variant. Limited data suggest a frequent association of FLCIS with invasive carcinoma. However, there is a paucity of information to guide management. We aimed to study imaging features associated with pathologic upgrade rates for patients with FLCIS identified on core biopsy (CB) undergoing surgical excision (SE).
Methods: Patients with FLCIS identified on CB were selected from our institutional pathology database. Patients were excluded if pleomorphic LCIS was also present on CB. Clinical, radiologic, and pathologic features were reviewed. We examined imaging features that led to CB and those associated with upgrade to invasive cancer or ductal carcinoma in situ (DCIS) on SE.
Results: We identified 15 patients with FLCIS on CB. One patient had FLCIS at two different intervals, resulting in 16 events. The median age at diagnosis was 60 years (range 35-77 years). Imaging features which prompted CB included calcifications (37.5%, n=6), mass with calcifications (12.5%, n=2), asymmetry with calcifications (6.25%, n=1), calcifications with non-mass enhancement (NME) on MRI (12.5%, n=2), mass (12.5%, n=2), architectural distortion (12.5%, n=2), and NME on MRI (6.25%, n=1). In most cases of FLCIS, SE was performed (14/16; 87.5%) which included 12 excisional biopsies/lumpectomies and 2 mastectomies. Endocrine therapy was utilized in 2/14 patients (14%) prior to surgery for 1 and 2.5 years, respectively. Surveillance was recommended for 2/16 patients (13%) one who received endocrine therapy. Both patients had biopsy for small areas of indeterminate calcifications (3.8 and 1.8 mm). Pathologic upgrade on SE was identified in 7/14 cases (50%), invasive lobular carcinoma (ILC) in 6/14 (43%), and DCIS in 1/14 (7%). Imaging features of cases with and without pathologic upgrade on SE are summarized in Table 1. Mammographic calcifications were present in 9 cases where SE was performed with upgrade in 7/9 cases (78%), ILC in 6/9 (67%), and DCIS in 1/9 (11%). Mammographic calcifications were present on imaging in all cases with a pathologic upgrade on SE.
Conclusion: Patients with FLCIS on CB presenting with mammographic calcifications were more likely to have pathologic upgrade on SE. Given the high upgrade rates in this setting, 78% overall and 67% with ILC, complete SE of indeterminate calcifications should be performed. Sentinel lymph node biopsy should also be considered at SE, particularly when mastectomy is performed or the area for SE is large. Additional studies that evaluate the correlation between imaging findings and pathologic SE upgrade rates are necessary to confirm these findings.
