Skull base chordomas: a management challenge

Abstract

✓ Because of their critical location, invasive nature, and aggressive recurrence, skull base chordomas are challenging and, at times, frustrating tumors to treat. Both radical surgical removal and high-dose radiation therapy, particularly proton beam therapy, reportedly are effective in tumor control and improve survival rates. The authors posit that these tumors are best treated with radical surgery and proton—photon beam therapy. During the last 5 years, they treated 25 patients (15 females and 10 males) who harbored pathologically diagnosed skull base chordomas. The mean age of the patients was 38.4 years (range 8–61 years). Previous surgery or radiation therapy was performed at other institutions in seven and two patients, respectively. The authors performed 33 surgical procedures on 23 patients. Radical removal (defined as absence of residual tumor on operative inspection and postoperative imaging) was achieved in 10 patients; subtotal resection (defined as resection of > 90% of the tumor) was achieved in 11 patients; and partial resection (defined as resection of < 90% of the tumor) was achieved in two patients. Radical surgical removal included not only the excision of soft-tumor tissue, but also extensive drilling of the adjacent bone. Adjuvant therapy consisted of postoperative combined proton—photon beam therapy (given to 17 patients and planned for one patient) and conventional radiation therapy (two patients); three patients received no adjunct therapy. To date, four patients have died. One patient who had undergone previous surgery and sacrifice of the internal carotid artery died postoperatively from a massive stroke; one patient died from adenocarcinoma of the pancreas without evidence of recurrence; and two patients died at 25 and 39 months of recurrent tumor. Permanent neurological complications included third cranial nerve palsy (one patient) and hemianopsia (one patient); radiation necrosis occurred in three patients. Of the 21 patients followed for more than 3 months after surgery, 16 have had no evidence of recurrence and five (including the two mortalities noted above) have had recurrent tumors (four diagnosed clinically and one radiologically). The mean disease-free interval was 14.4 months. A longer follow-up period will, hopefully, support the early indication that radical surgical removal and postoperative proton—photon beam therapy is an efficacious treatment. The use of skull base approaches based on the tumor classification introduced in this paper is associated with low mortality and morbidity rates.