PURPOSE: To evaluate the clinical and imaging findings of tubular carcinoma of the breast. MATERIALS AND METHODS: We retrospectively assessed the clinical and imaging findings of ten lesions of pathologically proven tubular carcinoma in nine patients, also evaluating the mammographic findings and categorizing the mass according to the ACR BI-RADS classification. The ultrasonographic findings were assessed in terms of shape, echogenicity, margin and posterior shadowing, and in four cases the size of nodules at physical examination was compared with the mammographic, ultrasonographic and pathologic findings. RESULTS: Nine lesions were palpable at physical examination. Bilateral tubular carcinoma of the breast was found in one patient, and unilateral single lesions in the others. There was no metastasis and no death within an average of 666 (range, 163) days of surgery. At mammography, masses were detected in six cases; the features, observed were a lobular or irregular shape (6/6), a spiculated margin (3/6) and high density (5/6). Ultrasonography showed that all unilateral lesions were hypoechoic (8/8), with a lesion height-to-width ratio of greater than 1.0 in seven of these, an ill-defined margin in sis, and posterior acoustic shadowing in seven. Mean nodule diameter was 1.17 cm at physical examination, 1.09 cm at mammography, 0.86 cm at ultrasonography and 0.80 cm at pathological evaluation. CONCLUSION: Most tubular carcinomas were palpable in spite of their small size, and their postoperative prognosis was good. Ultrasonography is useful in the detection of mammographically occult tubular carcinoma and for measuring the size of lesions.