Aims: Sweat-gland tumours (SGTs) are uncommon, but malignant varieties are very rare. We have added our data on 30 new cases seen at the Royal Marsden NHS Foundation Trust to the published literature, particularly concentrating on clinical issues. We include a literature review.
Materials and methods: The Royal Marsden NHS Foundation Trust database was searched for cases of SGT from 1972. Data were collected on all cases, including patient demographics and tumour characteristics, treatment and outcome.
Results: Thirty cases were confirmed histologically to be SGTs. Fourteen were malignant, 15 benign and the degree of malignancy in one was histologically indistinguishable. Mean age was 55 years (64 for malignant, 47 for benign tumours). The 15 patients with benign tumours were almost all treated with complete excision. Those with local relapse underwent successful re-excision. Their 5-year disease-free survival was 78% and cause-specific survival was 100%. Twelve of the 14 malignant tumours had localised disease at diagnosis, one had nodal disease and one had metastatic tumour nodules. All except one were treated with wide local excision. The patient with nodal involvement also had a lymph-node dissection. Two received adjuvant radiotherapy to the tumour bed. One received a melphalan limb perfusion. Eight of the 14 had no relapse. Six had locoregional relapse, and four of these also developed distant metastases. Visceral disease was always fatal. Radiotherapy and chemotherapy at relapse were unsuccessful. Five-year disease-free survival was 45%, and cause-specific survival was 57%.
Conclusion: These rare tumours should be treated initially with complete wide local excision. In malignant tumours, lymph-node involvement is a poor prognostic sign. Wide local excision remains the primary treatment. Adjuvant radiotherapy may be useful in high-risk cases.