Oesophageal cancer: location, location, location.

At the request of the American Joint Committee on Cancer (AJCC), non-anatomic (non-TNM) classifications were evaluated and important classifications incorporated into staging recommendations for oesophageal cancer in the 7th edition of the Cancer Staging Manual [1]. Cancer location, histopathological cell type and histological grade were demonstrated to enhance cancer staging [2]. Adenocarcinoma location was overwhelmingly in the lower thoracic oesophagus (96%), and thus the influence of cancer location on adenocarcinoma staging could not be evaluated [2, 3]. However, location was an important classification for squamous cell cancer. Distribution of squamous cell cancer location in worldwide data was upper thoracic (10%), middle thoracic (58%) and lower thoracic (32%) [3]. Only addition of histological grade to TNM improved staging of squamous cell cancers confined to the mucosa and submucosa (pT1). However, a complex interplay of cancer location and histological grade added to staging of pT2-T3N0M0 squamous cell cancer, such that four combinations were identified (Fig. 1). These ranged from lower thoracic well-differentiated (G1) squamous cell cancers (stage IB), which had the best survival, to middle and upper thoracic moderately differentiated to poorly differentiated (G2–G3) squamous cell cancers (stage IIB), which had the worst survival. G2– G3 lower thoracic squamous cell cancers and G1 upper and middle thoracic squamous cell cancers were grouped together (stage IIA), with intermediate survival. Non-anatomical classifications, including cancer location, did not influence staging of advanced squamous cell oesophageal cancer (T4 and N+) [1, 3]. Shi et al. [4] present their single-institution experience, analysing the importance of cancer location in squamous cell cancer. Prompted by the famous real estate quote, we reviewed their data and analysis (cancer location), the Asian experience (geographic location) and timing of this publication (temporal location).