Recommendations for the reporting of surgically resected specimens of colorectal carcinoma.

The reporting of colorectal cancer is facilitated by the provision of a checklist giving the features required for good patient care. However, the practicalities of applying such a checklist may not be straightforward. Familiar examples include finding the prescribed number of lymph nodes, distinguishing mesenteric tumor deposits from replaced lymph nodes, and deciding if a cluster of malignant cells in a lymph node sinus counts as metastasis. Checklists have traditionally focused on prognostic factors and, particularly, tumor stage. It is becoming increasingly clear that additional factors, whether morphological or molecular, will be needed for future clinical management. It is also evident that prognosis is strongly influenced by the surgical technique used, most notably by the introduction of total mesorectal excision in the case of rectal cancer. Adjuvant therapy is playing an increasingly important role in the management of colorectal cancer, and it is inevitable that morphological and molecular markers will be used to predict responses to the expanding range of therapeutic modalities. Neoadjuvant or preoperative radiotherapy is being offered to patients with advanced rectal cancer and can greatly modify the pathologic findings in operative specimens. For all the preceding reasons, the work of diagnostic pathologists has become increasingly complex and demanding. The 6th edition of the TNM classification fails to meet many of the challenges posed by the realities of modern cancer management. In fact, by changing the rules for staging without strong justification and introducing diagnostic criteria that are unhelpful and lack a good evidence base, there is a real danger that the community of pathologists will fail to engage with reporting recommendations in a standardized manner and that the quality of reporting will decline.