Diagnosis of Ductal Carcinoma in Situ in Breast Biopsies for a Radiological Mass Lesion: Did We Miss Something?

ObjectivesDuctal carcinoma in situ (DCIS) is typically detected as microcalcifications on mammography but can occasionally present as a mass-forming lesion. This study examined the histopathologic features of DCIS and its histologic subtypes diagnosed on biopsies for radiologically detected mass lesions and evaluated their correlation with imaging findings and surgical outcomes.MethodsWe retrospectively reviewed 38 biopsies diagnosed as DCIS and its subtypes that were performed for radiologically detected mass lesions. Each lesion was assessed for architectural patterns, nuclear grade, necrosis, calcifications, estrogen receptor (ER) status, and coexisting benign lesions. Subsequent excision outcomes were available for 30 lesions to evaluate the presence of invasive carcinoma and mass-forming correlates. Statistical analyses were performed.ResultsInvasive carcinoma was found in 13 of 38 lesions (34%) upon excision. Among 25 non-invasive tumors, 15 (60%) had a benign lesion accounting for the mass. DCIS with desmoplastic stromal fibrosis (n = 4) showed a significantly higher nuclear grade (P = .0451). Specific DCIS morphological subtypes-including encapsulated papillary carcinoma, solid papillary carcinoma, papillary DCIS, and cystic apocrine DCIS-were identified as plausible causes of mass-forming lesions. No statistically significant histologic predictors of invasive carcinoma on excision were identified in our limited study cohort.ConclusionsDCIS with associated desmoplastic stromal fibrosis, along with some specific histologic subtypes, can cause mass-forming lesions on imaging. Histologic features alone are not reliable predictors of coexisting invasive carcinoma. Careful pathologic-radiologic correlation, including attention to benign mass-forming correlates, is essential for accurate diagnosis and clinical management.