Outcomes of high dose rate interstitial boost brachytherapy after external beam radiation therapy in head and neck cancer--an Indian (single institutional) learning experience.
OBJECTIVE
This study is to assess efficacy and toxicity associated with external beam radiation therapy (EBRT) and high dose rate (HDR) interstitial Iridium-192 ((192)Ir) brachytherapy for the treatment of squamous carcinoma of the oropharynx and oral cavity.


METHODS
Between July 2004 and June 2006, 33 patients with oropharynx and oral cavity carcinomas were treated with (192)Ir interstitial implants after EBRT at Medical College Hospital, Kolkata. Fifteen patients had early stage disease (Stage I and II) and 18 had advanced stage disease (Stage III and IV). All received EBRT to a median dose of 50Gy (range, 46-66Gy) to the primary tumor and regional lymph nodes before brachytherapy. Node-positive patients with residual neck disease also underwent neck dissection. Brachytherapy dose (HDR) in combination with EBRT varied from 14 to 21Gy, 3-3.5Gy per fraction, two fractions daily. Locoregional control, freedom from disease, and complications were assessed.


RESULTS
Followup duration was between 18 and 40 months. At the end of treatment with radiation, 79% achieved complete response (CR) (p<0.009), 21% achieved partial response (PR) and the ultimate control rate (including surgical salvage) was 100% and 78% for early and advanced disease, respectively (p<0.108). Three (9%) patients failed locally after CR. No distant metastasis was seen during followup. Grade 3 mucositis was seen in 12% cases. Transient hemorrhage occurred in 3 (9%) patients and local infection in 1 (3%) patient. Severe dysphagia was seen in 1 (3%) patient. 5/33 (15%) patients experienced xerostomia (Grade 3-4), but almost all patients had Grade 1-2 xerostomia.


CONCLUSIONS
Oropharyngeal and oral cavity tumors can be effectively treated with (192)Ir implant boost after EBRT. Local control is excellent and complication rates are acceptable.
Patra
Niladri B
NB
Department of Radiotherapy, Medical College Hospital, Kolkata, India. Electronic address: nbpatra@yahoo.co.in.
Goswami
Jyotirup
J
Department of Radiotherapy, Medical College Hospital, Kolkata, India.
Basu
Swapnendu
S
Department of Radiotherapy, Medical College Hospital, Kolkata, India.
Chatterjee
Kaushik
K
Department of Radiotherapy, Medical College Hospital, Kolkata, India.
Sarkar
Shyamal K
SK
Department of Radiotherapy, Medical College Hospital, Kolkata, India.
D000328:Adult; D000368:Aged; D001918:Brachytherapy / Q000379:methods*; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000532:radiotherapy*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*; D006801:Humans; D007194:India; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome