Pure tubular carcinoma and axillary nodal metastases

Background: Pure tubular carcinoma of the breast is a rare subtype with a low incidence of axillary lymph node metastases. The aim of this study was to determine the frequency of axillary lymph node metastasis in patients with pure tubular carcinoma. Methods: We identified patients diagnosed with tubular carcinoma from 1987 to 2009 from our institution's tumor registry. Pathology slides were reviewed, and pure tubular carcinoma was defined as ≥90% tubule formation, low nuclear grade, and rare to no mitoses. Medical records were reviewed for clinicopathologic data including tumor size, number of positive and negative axillary lymph nodes, treatment, and recurrence. Results: We identified 105 cases of pure tubular carcinoma of the breast in 103 patients. Median tumor size was 0.8 (range 0.1-1.8) cm. Nodal staging was performed in 93 cases (89%). Five patients (5.4%) had positive lymph nodes, and two patients (2.2%) had isolated tumor cells. All patients with lymph node metastases had tumors >0.8 cm in size. At 5.2 years' follow-up, no patients have developed recurrence or metastases, or have died from breast cancer. Conclusions: Axillary lymph node metastases are not common in small pure tubular carcinomas. Nodal staging may be omitted in small pure tubular carcinomas.