Comparative Value of Mammography, Fine-Needle Aspiration Biopsy, and Core Biopsy in the Diagnosis of Invasive Lobular Carcinoma

Abstract

Invasive lobular carcinoma of the breast (ILC) is a lesion often cited as being more difficult to diagnose than invasive ductal carcinoma. Our objective was to assess the role of mammography, fine‐needle aspiration biopsy (FNAB) and large core needle biopsy (LCNB) in the diagnosis of invasive lobular carcinoma of the breast. We reviewed 1,074 consecutive patients with invasive cancers of the breast, of which 102 (9%) were ILC. All the patients with ILC had mammography, 66 had FNAB, and 15 had LCNB performed. Of the patients with ILC, 95 of 102 (93%) had an abnormal mammogram. Seven patients (7%) had a negative mammogram. The most common radiographic finding in patients with ILC was a spiculated mass (42%). The average size of the cancers detected by mammography was 1.17 cm, with no significant effect of size on the ability to detect cancer based on its mammographic presentation for p > .05. Sixty‐six patients had FNAB, with a postive diagnosis of cancer in 27 (41%) and suspicious or atypical aspiration in 20 patients (30%). Nineteen patients (28%) had false‐negative aspirates. There was no significant difference in size for patients whose cytology demonstrated malignant, suspicious, atypical, or benign aspirates, F (4,56) = 1.01, p > .05. For the fifteen patients who had LCNB, a definitive diagnosis of ILC was made in 13 cases (87%), with another patient having a diagnosis that was “suspicious” for ILC. One patient had a false‐negative LCNB. ILC can be detected by mammography, in most instances. FNAB may fail to diagnose this cancer, particularly if the cancer is of low nuclear grade. The lack of reliability of FNAB for diagnosis of ILC, which may occur in some cases is due to the discontinuous infiltrative pattern and the intrinsic cytologic characteristics of this cancer. LCNB is a complementary diagnostic procedure when the FNAB is nondiagnostic to demonstrate the presence of ILC. In the presence of a dominant mass by palpation and a clinical suspicion of the presence of ILC, a negative mammography or a benign FNA should not preclude a surgical biopsy.