Interstitial brachytherapy with or without external beam irradiation in head and neck cancer: Institute rotary cancer hospital experience

Iridium-192 interstitial brachytherapy is practiced infrequently in develop ing countries, even where head and neck cancer is a major neoplasm and the technique could provide good results. This report from India is presented a s an audit to validate the benefit of brachytherapy. One hundred and six head and neck cancer patients were treated by interstit ial brachytherapy alone (n = 29) or combined with external irradiation (n = 77). The oral cavity and the oropharynx together constituted 82% of the si tes of implanted tumours; 75% were T1-2N0 status. Brachytherapy was carried out using afterloaded plastic catheters and the Paris dose prescription sy stem was followed. External cobalt-60 beam portals covered the primary and the neck. The median duration of follow-up was 22 months. The median dose of brachyth erapy used alone was 60 Gy. With combined treatment, the median external ra diotherapy and brachytherapy doses were 50 Gy and 25 Gy respectively. The m edian brachytherapy dose rate was 0.5 Gy/h. Primary and nodal recurrences w ere recorded in 41/106 (38.7%) and 18/106 (17.0%) patients at median interv als of 15 and 13 months respectively. Implant site failure was more common after combined treatment than with brachytherapy alone (42.8% versus 27.5%) , but it did not reach statistical significance in this analysis (P = 0.15) . Kaplan-Meier actuarial 5-year estimates showed 52% and 87% disease-free a nd overall survivals. Iridium-192 interstitial implants in suitably selected head and neck cancer patients can improve the radiotherapeutic results, with the promise of org an conservation in 50%. In India, the practice should be established in mor e radiotherapy centres and could be utilized in 10 000-25 000 head and neck cancer patients annually.