Effects of intralesional ³²P in refractory patients with head and neck tumors

Abstract

16529 Background: The clinical outcome of refractory head and neck cancer patients remains poor despite novel treatment strategies. In this pilot study we investigated the efficacy of intratumoral injection of 32-P chromic phosphate in 14 patients with refractory head and neck cancers in terms of response rates and overall survival. Methods: Fourteen patients (median age: 59 years) with either cytostatic drug-resistant tumors or tumors known to be primarily chemotherapy-resistant were entered into the study. After sonographic determination of the tumor volume, 32-P chromic phosphate (74–555 MBq) was injected into the central part of the tumor under sonographic guidance. Follow-up investigations included serial scintigraphy, sonographic examinations, and hematologic studies. Results: Injection of 32-P chromic phosphate into refractory head and neck tumors resulted in remarkable regression. The median survival of all patients was 7.8 months (range: 4–16). The response rate (partial response) was 57% (8 patients). However, 6 patients (43%) did not respond to the treatment. In 3 patients thrombocytopenia (grade I/II) was observed, but no other side effects were apparent. Significant pathologic and anatomic changes within the tumor tissue were demonstrated. In all cases examined, formation of a cyst within the area of central activity, surrounded by a centrifugal necrotic ring and a marginal fibrotic structure, was found. Conclusions: Lack of persistent systemic or local side effects, as well as noteworthy efficacy, are properties of this novel regional treatment modality with 32-P chromic phosphate. This modality deserves consideration for further clinical trials. No significant financial relationships to disclose.