1086 www.thelancet.com/oncology Vol 10 November 2009 Review Management of the neck after chemoradiotherapy for head and neck cancers in Asia: consensus statement from the Asian Oncology Summit 2009 Joseph T Wee, Benjamin O Anderson, June Corry, Anil D’Cruz, Khee C Soo, Chao-Nan Qian, Daniel T Chua, Rodney J Hicks, Christopher H K Goh, James B Khoo, Seng C Ong, Arlene A Forastiere, Anthony T Chan The addition of a planned neck dissection after radiotherapy has traditionally been considered standard of care for patients with positive neck-nodal disease. With the acceptance of chemoradiotherapy as the new primary treatment for patients with locally advanced squamous-cell head and neck cancers, and the increasing numbers of patients who achieve a complete response, the role of planned neck dissection is now being questioned. The accuracy and availability of a physical examination or of different imaging modalities to identify true complete responses adds controversy to this issue. This consensus statement will address some of the controversies surrounding the role of neck dissection following chemoradiotherapy for squamous-cell carcinomas of the head and neck, with particular reference to patients in Asia. Introduction Cervical metastasis is the most important prognostic factor in the treatment of head and neck cancers (figure); therefore, appropriate management of the neck is paramount. Early stage nodal disease can be controlled using single modality therapy, but more advanced nodal disease usually requires a multimodality approach. When surgery is the primary treatment for squamous-cell carcinoma of the head and neck (HNSCC), modified neck dissection followed by adjuvant radiation therapy is considered the standard for node-positive disease in the neck. Chemoradiotherapy is increasingly being accepted as the primary treatment strategy for many locoregionally advanced HNSCC (National Comprehensive Cancer Network guidelines) 1 and surgery is usually added electively, particularly for larger neck metastasis. However, more patients are showing a complete response to chemoradiotherapy and the continued role of a planned neck dissection after achievement of a complete response has been questioned. Prophylactic neck dissection Evidence based on long-term clinical outcomes, rather than extrapolations from prophylactic neck-dissection pathology, now shows that patients who achieve a complete clinical and radiological response to chemoradiation have a low (<5%) risk of isolated neck recurrence (table 1). 2–25 This data, initially from physical assessment only, comes from use of post-treatment CT scanning. The accuracy of a CT assessment of complete response has been questioned—a concern based on series that showed high rates of pathological positivity (30–40%) in neck specimens from patients who had a radiological complete response. 26–31 However, neck dissections were done early in these studies (4–6 weeks after treatment) and the viability and clonogenic capacity of the tumour cells was uncertain. With time, these cells become non-viable, otherwise we would see 30–40% regional failure rates in the neck following a radiological (CT) complete response. Studies of patients with a complete response as assessed by CT have mature long-term clinical follow-up and show very low regional relapse rates (median 5%, range 0–10%). These rates are very similar to the regional failure rates reported in the planned neck dissections series (median 8%, 0–25%). 32–43 One issue for patients with a CT-assessed complete response is the accuracy and availability of physical examination or imaging modalities to identify true complete responders. Several studies 17,18,44 have compared imaging modalities with pathological findings or long-term follow up. The sensitivities, specificities, positive and negative predictive values are summarised in table 2. Recent data also suggests an increasing trend towards post-chemoradiotherapy imaging using hybrid PET-CT, although there is no consensus with respect to the optimum timing or the clinical utility of this approach. With an absence of prospective randomised data, and conflicting results in some retrospective studies, this Lancet Oncol 2009; 10: 1086–92 See Reflection and Reaction page 1029 This is the second in a series of six consensus statements National Cancer Centre, Singapore (J T Wee FRCR, Prof K C Soo FRACS, J B Khoo FRCR); University of Washington, Seattle, WA, USA (Prof B O Anderson MD); Peter MacCallum Cancer Centre, Melbourne, Australia (J Corry FRANZCR, Prof R J Hicks FRACP); Tata Memorial Hospital, Mumbai, India (Prof A D’Cruz MS); State Key Laboratory of Oncology in Southern China, Sun Yat-sen University Cancer Center, Guangzhou, China (Prof C-N Qian MD); Queen Mary Hospital, University of Hong Kong, China (D T Chua FRCR); Singapore General Hospital, Singapore (C H K Goh FRCS); Mount Elizabeth Hospital, Singapore (S C Ong FRCR); Johns Hopkins University School of Medicine, Baltimore, MD, USA (Prof A A Forastiere MD); and Prince of Wales Hospital, Chinese University of Hong Kong, China (Prof A T Chan FRCP) Correspondence to: Dr Joseph T Wee, Division of Clinical Trials and Epidemiological Sciences, National Cancer Centre, 11 Hospital Drive, Singapore 169610 trdwts@nccs.com.sg Figure: Coloured CT scan of the neck of a patient with cancer (orange) of the larynx Sovereign, ISM/Science Photo Library