RESUMEN
BACKGROUND: Ductal carcinoma in situ (DCIS) in the male breast is a rare disease that to the authors' knowledge has been investigated to date only in small numbers. Compared with DCIS in the female breast, distinct clinical and morphologic differences have been suggested. METHODS: The files of the Armed Forces Institute of Pathology (AFIP) were searched for cases of pure DCIS and DCIS associated with invasive carcinoma (DCISAIC) in male patients. A total of 280 cases of pure DCIS and 759 invasive mammary tumors were identified; 114 cases (including 84 pure DCIS and 30 DCISAIC) were studied for this preliminary report. All cases were reviewed and classified according to specific subtypes (papillary, cribriform, solid, micropapillary, and comedo) and grades of DCIS. Basic clinical data were extracted from the patients' charts. RESULTS: Men with pure DCIS presented at a median age of 65 years, with a typically nodular, retroareolar, partially cystic mass that frequently was associated with a nipple discharge. The median duration of symptoms was 2 months for patients with pure DCIS and 6 months for patients with DCISAIC. Histologically, the predominant appearance of DCIS (in 74% of cases) was that of a papillary carcinoma often with a superimposed cribriform pattern. Intraductal extension beyond the main papillary lesion was common. It is interesting to note that the pure DCIS cases in this series were uniformly of either low or intermediate grade; high grade or comedocarcinomas were only observed within the group of DCISAIC. No significant morphologic differences between pure DCIS and DCISAIC were encountered, although DCISAIC did show relatively more cellular atypia with more frequent necrosis compared with pure DCIS. CONCLUSIONS: DCIS in the male breast is a distinct lesion that occurs at an older age and displays a significantly different distribution of morphologic subtypes compared with its female counterpart. It presents most frequently as an intraductal papillary carcinoma, and less commonly as a nonpapillary cribriform, solid, or micropapillary DCIS. In the current study the majority of pure DCIS cases were low grade (AFIP Grade 1) with occasional cases displaying necrosis (AFIP Grade 2); high grade pure DCIS appears to be a rare lesion in the male breast. In contrast, DCIS associated with invasive carcinoma more frequently is of higher grade.