Proton beam radiation therapy for skull base adenoid cystic carcinoma.
OBJECTIVE
To determine the treatment outcome and prognostic factors in patients with adenoid cystic carcinoma of the skull base treated with proton beam radiation therapy.


METHODS
Retrospective analysis.


METHODS
Massachusetts General Hospital, Massachusetts Eye and Ear Infirmary, and Harvard Medical School, Boston.


METHODS
From 1991 to 2002, 23 patients with newly diagnosed adenoid cystic carcinoma with skull base extension were treated with combined proton and photon radiotherapy. There was tumor involvement of the sphenoid sinus in 61% of patients (14), nasopharynx in 61% (14), clivus in 48% (11), and cavernous sinus in 74% (17). The extent of surgery was biopsy alone in 48% (11), partial resection in 39% (9), and gross total resection with positive margins in 13% (3). The median total dose to the primary site was 75.9 cobalt-gray equivalent. The median follow-up of all surviving patients was 64 months.


METHODS
Locoregional control and disease-free survival and overall survival rates.


RESULTS
Tumors recurred locally in 2 patients at 33 and 68 months, respectively. No patients developed neck recurrence. Eight patients had distant metastasis as the first site of recurrence. The local control rate at 5 years was 93%. The rate of freedom from distant metastasis at 5 years was 62%. The disease-free and overall survival rates at 5 years were 56% and 77%, respectively. In multivariate analysis, significant adverse factors predictive for overall survival were change in vision at presentation (P = .02) and involvement of sphenoid sinus and clivus (P = .01).


CONCLUSIONS
High-dose conformal proton beam radiation therapy results in a very encouraging local control rate in patients with adenoid cystic carcinoma of the skull base. Changes in vision at presentation and tumor involvement of the sphenoid sinus and clivus are important prognostic factors.
Pommier
Pascal
P
Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA 02114, USA.
Liebsch
Nobert J
NJ
Deschler
Daniel G
DG
Lin
Derrick T
DT
McIntyre
James F
JF
Barker
Fred G
FG
Adams
Judy A
JA
Lopes
Vrishali V
VV
Varvares
Mark
M
Loeffler
Jay S
JS
Chan
Annie W
AW
D000328:Adult; D000368:Aged; D002244:Carbon; D003528:Carcinoma, Adenoid Cystic / Q000401:mortality / Q000532:radiotherapy*; D002426:Cavernous Sinus; D003388:Cranial Fossa, Posterior; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000473:pathology; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D009502:Neutrons; D010255:Paranasal Sinus Neoplasms / Q000473:pathology; D011379:Prognosis; D011522:Protons; D011878:Radiotherapy / Q000009:adverse effects; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D016879:Salvage Therapy; D019292:Skull Base Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D013101:Sphenoid Sinus; D015996:Survival Rate; D016896:Treatment Outcome
D011522:Protons; D002244:Carbon