To demonstrate the feasibility of helical tomotherapy (HT)-based intensity-modulated radiotherapy (IMRT) for the treatment of synchronous primary cancers arising from the head and neck.
14 consecutive patients with histologically proven squamous cell carcinoma of the head and neck were determined to have a second primary cancer in the upper aerodigestive tract on further evaluation and were treated with HT using simultaneous integrated boost IMRT. Megavoltage CT scans were acquired daily as part of an image-guided registration protocol. Concurrent platinum-based systemic therapy was given to nine patients (64%).
HT resulted in durable local control in 21 of the 28 primary disease sites irradiated, including a complete clinical and radiographic response initially observed at 17 of the 20 sites with gross tumour. The mean displacements to account for interfraction motion were 2.44 ± 1.25, 2.92 ± 1.09 and 2.31 ± 1.70 mm for the medial–lateral (ML), superior–inferior (SI) and anteroposterior (AP) directions, respectively. Table shifts of >3 mm occurred in 19%, 20% and 22% of the ML, SI and AP directions, respectively. The 2-year estimates of overall survival, local-regional control and progression-free survival were 58%, 73% and 60%, respectively.
The effectiveness of HT for the treatment of synchronous primary cancers of the head and neck was demonstrated.
Advances in knowledge:
HT is a feasible option for synchronous primary cancers of the head and neck and can result in long-term disease control with acceptable toxicity in appropriately selected patients.