Aim: Anal cancer is a rare neoplasm. According to a European Organization for Research and Treatment of Cancer multivariate analysis, synchronous inguinal lymph node metastasis occurs in 10-25% of patients and constitutes an independent prognostic factor for local failure and overall mortality.
Methods: Inguinal lymph node status was assessed using the sentinel node technique in 35 patients with anal cancer.
Results: Histology revealed 23 squamous carcinomas, 10 basaloid carcinomas, 1 squamous carcinoma with basaloid areas and 1 spinocellular epithelioma associated with areas of Bowen's disease. Disease stage was T1 in 5 patients, T2 in 18, T3 in 11 and T4 in 1 patient. Lympho-scintigraphy using a GE Millennium gamma camera was performed after peritumoral injection of 37 MBq of 99mTc colloid. Surgical sentinel node biopsy with a portable Scintiprobe MR 100 (Politech, Carsoli, Italy) had a detection rate of 97.1%. Inguinal metastases were detected in 7 (20%) patients, in 2 of which metastasis was bilateral.
Conclusions: Given the correlation between prognosis and node involvement, sentinel node biopsy can be considered a simple method for adequate pretreatment staging of anal carcinoma. Use of the technique could avert the need for prophylactic inguinal radiotherapy in N0-N1 patients, thus reducing the morbidity associated with inguinal radiotherapy. Consistent follow-up is required to evaluate long-term results: