Journal of Surgical Oncology 2007;96:457–463 Analysis of Patients with False Negative Mammography and Symptomatic Breast Carcinoma IAN G. MURPHY, MB, 1 MARY F. DILLON, MB, 1 * ANN O’ DOHERTY, MB, 2 ENDA W. McDERMOTT, MCh, 1 GABRIELLE KELLY, PhD, 3 NIALL O’HIGGINS, MCh, 1 AND ARNOLD D.K. HILL, MCh 1 1 Department of Surgery, St Vincent’s University Hospital, Elm Park, Dublin, Ireland 2 Department of Radiology, St Vincent’s University Hospital, Elm Park, Dublin, Ireland 3 Department of Statistics, University College Dublin, Dublin, Ireland Aim: False-negative mammograms may result in a delay in breast carcinoma diagnosis and have important implications for patient care. In this study, the characteristics of symptomatic patients with false-negative mammograms were analysed. Methods: Patients with symptomatic breast carcinoma were identified over a 10-year period (1994–2004). One hundred and twenty-four patients had false-negative preoperative mammograms and 1241 patients had abnormal preoperative mammo- grams. Clinical presentation, diagnostic methods and pathology were analysed. False- negative mammograms were reviewed by a specialist breast radiologist. Results: Following retrospective review, 42% of false-negative mammograms were re-categorised as suspicious. The most commonly misinterpreted lesion was architectural distortion/asymmetrical density. Adjuvant ultrasound, where performed (n ¼ 27), raised the level of suspicion in 93% of cases. Patients with false-negative mammograms were more likely to be younger (P < 0.0001), present with nipple discharge (P ¼ 0.002) and have smaller tumours (P < 0.0001). Their tumours were more frequently located outside the upper outer quadrant (P ¼ 0.002). False- negative mammography led to a delay in diagnosis of >2 months in 12 patients. Conclusion: Symptomatic patients with false-negative mammograms often demon- strate definite abnormalities on imaging, the most common of which is architectural distortion/asymmetrical density. Those at particular risk were younger patients, those with nipple discharge, and patients with lesions located outside the upper outer quadrant. J. Surg. Oncol. 2007;96:457–463. ß 2007 Wiley-Liss, Inc. KEY WORDS: mammography; breast neoplasm; sensitivity and specificity; ultrasonography; signs and symptoms; palpation INTRODUCTION False negative mammography remains a significant challenge for clinicians as it can potentially lead to a ‘missed’ or delayed diagnosis of breast carcinoma. In an era where image-guided biopsy is becoming the principal method of diagnosing breast carcinoma, a high level of clinical suspicion is required to manage patients with equivocal clinical signs and benign mammography. The rate of false negative mammograms reported in the literature is as high as 8 – 34% [1 – 9]. While these patients and the type of lesions overlooked have been well characterised in patients with screen-detected carcinoma [10–15], less is known about the profile and outcome of patients presenting to a symptomatic breast service who have false negative mammograms. The purpose of our study was to review the radio- logical, clinical and pathological features of those patients presenting to a symptomatic clinic with false *Correspondence to: Mary F. Dillon, MB, Department of Surgery, St Vincent’s University Hospital, Elm Park, Dublin 4, Ireland. Fax: 353 1 2693479. E-mail: maryfdillon@hotmail.com Received 13 September 2006; Accepted 5 February 2007 DOI 10.1002/jso.20801 Published online in Wiley InterScience (www.interscience.wiley.com). ß 2007 Wiley-Liss, Inc.