Low-dose fractionated radiation as a chemopotentiator of neoadjuvant paclitaxel and carboplatin for locally advanced squamous cell carcinoma of the head and neck: results of a new treatment paradigm

Abstract

Purpose: Current therapies for locally advanced squamous cell carcinoma of the head and neck (SCCHN) result in 50% long-term remission. Low-dose radiotherapy (<100 cGy) induces enhanced cell killing in vitro via the hyper-radiation sensitivity phenomenon but has not been used in the clinical setting. On the basis of the demonstrated synergy between chemotherapy and low-dose fractionated RT, a novel neoadjuvant therapy was designed using low-dose fractionated RT as a chemopotentiator for locally advanced SCCHN.

Methods and materials: Forty patients with locally advanced SCCHN received paclitaxel (225 mg/m2), carboplatin (area under the curve of 6), and four 80-cGy fractions of radiotherapy (two each on Days 1 and 2). This sequence was repeated on Days 22 and 23.

Results: Of the 40 patients enrolled, 39 were assessable. Grade 3 or worse toxicities included neutropenia (50%), infection (13%), arthralgias/myalgias (3%), skin (8%), lung (3%), and allergic reaction (3%), with no Grade 5 toxicity. The response was assessed radiographically and by panendoscopy. At the primary site, 11 patients (28%) had a complete response, 24 (62%) had a partial response, and 4 (10%) had stable disease. Of those with lymph node involvement, 10 (31%) had a complete response, 12 (38%) a partial response, 9 (28%) had stable disease, and 1 (3%) had progressive disease. The overall response rate was 82%.

Conclusion: Low-dose fractionated RT combined with paclitaxel and carboplatin is effective in SCCHN and has a similar toxicity profile to chemotherapy alone. This novel approach provided a response rate of 90% at the primary site and a nodal response rate of 69%. Additional scientific investigation of this new treatment paradigm is warranted.