Background: There is little published information pertaining to elective inguinal lymph node irradiation for carcinomas originating in the pelvis that place the inguinal lymph nodes at risk.
Methods: Between October 1964 and October 1988, 164 patients with primary carcinomas originating in the pelvis that placed the inguinal lymph nodes at risk for subclinical disease received elective inguinal lymph node irradiation at the University of Florida. All patients had a minimum follow-up of 2 years from the start of radiation therapy. Primary sites included the penis, urethra, vulva, anal canal, distal rectum (within 4 cm of the verge), and the cervix or vagina when the tumor involved the distal one-third of the vagina. In 148 patients, both groins were clinically negative; in 16 patients, one groin was positive and the other negative by clinical examination. Treatment techniques were individualized according to the primary site. Tumor doses to the inguinal lymph nodes varied, although more than 70% of patients received 4500-5000 cGy (range, 2650-6780 cGy) over 5 weeks (range, 2-7 weeks) at 180-200 cGy per fraction. Patients were excluded from the analysis of disease control in the inguinal area if they died less than 2 years from treatment with the inguinal lymph nodes continuously disease free or if they experienced recurrence at the primary site with the inguinal lymph nodes clinically negative at the time of recurrence.
Results: The inguinal lymph node control rate was 96% (101 of 105). No patient in whom recurrent disease developed in the inguinal lymph nodes underwent salvage therapy.
Conclusions: Elective irradiation of the inguinal lymph nodes is highly effective in controlling subclinical disease from carcinomas originating in the pelvis and can be accomplished with minimal acute or long-term complications.