To report the long-term results of vulvectomy, node dissection, and postoperative nodal irradiation using a midline vulvar block in patients with node positive vulvar cancer.

From 1971 through 1992, 27 patients with carcinoma of the vulva and histologically involved inguinal lymph nodes were treated postoperatively with radiation therapy after radical vulvectomy and bilateral lymphadenectomy (n = 25), radical vulvectomy and unilateral lymphadenectomy (n = 1), or hemivulvectomy and bilateral lymphadenectomy (n = 1). Federation Internationale de Gynecologic et d'Obstetrique stages were III (n = 14), IVA (n = 8), and IVB (n = 5) squamous cell carcinoma. Inguinal lymph nodes were involved with tumor in all patients (average number positive = 4, range 1-15). Postoperative irradiation was directed at the bilateral groin and pelvic nodes (n = 19), unilateral groin and pelvic nodes (n = 6), or unilateral groin only (n = 1). These 26 patients had the midline blocked. In addition, one patient received irradiation to the entire pelvis and perineum. Doses ranged from 10.8 to 50.7 Gy (median 45.5) with all patients except 1 receiving > or = 42.0 Gy.

Actuarial 5-year overall survival and disease-free survival estimates were 40% and 35%, respectively. Recurrences developed in 63% (17/27) of the patients at a median of 9 months from surgery (range 3 months to 6 years) and 15 of these have died; two patients with recurrences are surviving at 24 and 96 months after further surgery and radiation therapy. Central recurrences (under the midline block) were present in 13 of these 17 patients (76%), either as central only (n = 8), central and regional (n = 4), or central and distant (n = 1). Additionally, three patients developed regional recurrences and one patient developed a concurrent regional and distant relapse. One patient developed a squamous cell cancer of the anus under the midline block 54 months after the initial vulvar cancer and an additional patient developed transitional cell carcinoma of the ureter (outside the radiation field) 12 months after diagnosis. Factors associated with a decreased relapse-free survival included increasing Federation Internationale de Gynecologic et d'Obstetrique stage (p = 0.01) and invasion of the tumor into the subcutaneous (SC) fat or deep soft tissue (p = 0.05). Chronic lower extremity edema developed in four patients, but there have been no other complications.

Radical vulvectomy has often been considered sufficient central treatment for vulvar carcinoma, with postoperative irradiation directed only to the nodes. Although designed to protect the radiosensitive vulva, use of a midline block in this series resulted in a 48% (13/27) central recurrence rate, much higher than the 8.5% rate previously reported with this technique. Routine use of the midline block should be abandoned and, instead, postoperative irradiation volumes should be tailored to the individual patient.