Phase II/III Randomized Controlled Trial of Concomitant Hyperfractionated Radiotherapy plus Cetuximab (Anti-EGFR Antibody) or Chemotherapy in Locally Advanced Head and Neck Cancer.

Introduction: Globally, there is marked variation in overall incidence and presentation of head and neck cancers, these cancers account for 11.5 per 100,000 population in G.C.C states. Concomitant chemotherapy and external beam radiotherapy (EBRT) is indicated in such cancers with aim of organ preservation, control and possible cure. Hyper fractionated radiotherapy with concomitant chemotherapy or cetuximab is a lesser explored option. In this study we wish to assess the tolerability and efficacy of cetuximab with altered fractionation and compare this with the chemotherapy (cisplatin).

Materials And Methods: This is a randomized controlled study from a single institute in Kuwait. Locally advanced head and neck cancer cases excluding cancer nasopharynx are enrolled for the study. Stage III or stage IV-A cases were enrolled with histopathology squamous cell carcinoma. Patients were randomized into 2 arms. Arm A: to receive platinum-based CT i.e. cisplatin in a dose of 100 mg/m2 3-weekly or 40 mg/m2 weekly during radiation; Arm B: received cetuximab with a loading dose 400 mg/m², one week before radiation followed by weekly dose of 250 mg/m² during radiation. Radiotherapy was delivered using intensity modulated radiotherapy (IMRT) or 3D-conformal radiotherapy (CRT). The primary objective was to evaluate whether the use of cetuximab with concurrent hyperfractionated radiation regimen will have loco regional control rates (LC) and Disease-free survival (DFS) that are comparable to concurrent cisplatin in patients with LAHNC. The secondary endpoints were to compare the impact of using concurrent cetuximab vs chemotherapy regimen on Overall Survival of patients (OS) and acute and late adverse events.

Results: From November 2012 to November 2017, 40 patients were randomized. The median age of was 51 years (range 27-72 years). Thirty-five patients are male and remaining was female. 14 patients have their primaries in larynx, 11 in oropharynx, 8 in oral cavity, and 5 has tumor in hypopharynx. Two patients had disease in nasal sinus or overlapping subsides. 50% has T4 lesions while 35% has T3 lesions, Nodal status was (N0-1) in 20 patients and (N2-3) in 20 patients. Overall staging showed a majority to have stage IV disease (63%). HPV was negative in 2 cases in Arm 1 and positive in 2 cases in Arm 2. 22 patients were randomly allocated in Arm A (platinum-based) while 18 were in Arm B (cetuximab). CR was achieved in 59% in arm A vs 50% in Arm B, while PR was 27.3% and 27.8% respectively. Disease progressed in 2 patients in Arm B only. Out of these 40 patients, 14 patients failed (6 and 8 in arm A and B respectively). Locoregional failure was documented in 6 (27.3%) vs 7 (38.9%) of arm A and B respectively, which was statistically not significant possibly related with lower number of cases. 2 years DFS was 56.5% vs 77.3% in cisplatin vs cetuximab arm (denoting nonsignificant increase of relapse rate in cisplatin arm). However, 2 years OS was 80.7% vs 57.3% in cisplatin and cetuximab arm respectively (p value=0.04).

Conclusion: Though cetuximab has lesser side effects but it is not indicated in treatment of LAHNC. Concurrent cisplatin is a trusted option for concomitant setting regardless of the HPV status and tumor location. However, in the context of cisplatin ineligible patients, cetuximab should be used only with hyper fractionation. This preliminary study could represent a good core of large international multicenter RCT.