Intracystic Papillary Carcinoma (IPC) of the Breast: A Clinicopathological Study of 125 Cases
Isabel Alvarado-Cabrero, Raquel Valencia-Cedillo, Sinuhe Barroso-Bravo. Mexican Oncology Hospital, IMSS, Mexico, DF, Mexico
Background: IPC is an uncommon breast neoplasm. Because of its rarity, data about its epidemiology is limited. On the other hand, IPCs have traditionally been considered to be a variant of ductal carcinoma in situ, however, it is not clear if some of these lesions might represent a special type of invasive carcinoma. The goals of this study were: to identify specific characteristics of patients (pts) with IPCs and investigate its natural history (behavior).
Design: We searched the pathology database from 1990-2010 for IPC and solid papillary carcinomas (SPCs). Two pathologists reviewed all H&E slides. We evaluated the expression of myoepithelial cell (MEC) markers, p63 and calponin as well as the expression of Estrogen Receptors (ER), Progesterone Receptors(PR) and HER2 in all cases. Clinical management and follow-up were obtained from clinical charts.
Results: 106 (85%) intracystic and 19 (15%) solid papillary carcinomas were the study group. The mean age at diagnosis was 59 years and the mean tumor size 2.2cm. From 106 IPCs cases, 82 were pure, 14 were IPC with microinvasion (IPC+Mi), and 10 cases were IPC with invasive carcinoma (IPC+IC). Six (32%) of SPCs were associated with invasive carcinoma (SPC+IC). All 125 cases showed complete absence of MEC at the periphery of the nodules, also, all tumors were ER and PR positive and HER2 negative. 52 pts underwent mastectomy, of these, 6 cases with IPC+IC, 3 with SPC+IC, 2 with pure IPC and 1 with pure SPC, respectively, had lymph node metastases. 73 pts underwent lumpectomy, of these pts, 48 received radiation and 25 hormonal treatment. Eight of 73 (11%) pts treated conservatively (1 with pure IPC, 4 with IPC+IC, one with IPC +Mi, and 2 with SPC+IC) recurred locally, including one who later developed lung metastases.
Conclusions: Pure IPCs and SPCs: have excellent prognosis; because they are strongly ER and PR positive, hormonal therapy should be pursued for its management; routine use of chemotherapy is clearly not appropiate. Sentinel Lymph node biopsy may be a prudent way to evaluate axillary involvement.
Tuesday, March 20, 2012 1:00 PM
Poster Session IV # 5, Tuesday Afternoon