Squamous cell carcinoma of the breast: clinico-pathologic implications and outcome

Abstract Aims: Pure squamous cell carcinoma (SCC) of the breast is a rare tumour and little is known about long-term outcome. We report our experience of a consecutive series of patients. Methods: All patients with SCC treated at our institution between 1970 and 2001 were included. The pathological features, outcome and prognosis were studied. Results: Eleven patients were identified. The median age was 55 (38–90) years and median follow-up was 62 (3–332) months. Four tumours were T1, three were T2 and three were T3 (one tumour size was unknown). There were seven poorly differentiated and three moderately differentiated SCC. Tumour grade could not be assessed in one patient. Primary treatment was mastectomy in six patients, wide local excision in four patients and radiotherapy in one patient. There was lymph node (LN) involvement in two patients. Oestrogen receptor status was assessed in seven patients and only one tumour was positive. Adjuvant chemotherapy was given to three patients and five patients received adjuvant radiotherapy. Two patients developed local recurrence at 5 and 12 months and three patients developed distant metastasis at 2, 36 and 306 months. Three patients were treated with chemotherapy at recurrence. Three patients have died of the disease, two are alive with disease and six remain well. The 2- and 5-year overall survival was 80% (SE=13%) and 67% (SE=16%) respectively. Large tumour size and positive LN status were prognostic indicators of poor outcome. Conclusion: SCC of the breast adopts an aggressive course with outcome comparable to poorly differentiated breast adenocarcinoma.