Author's response to reviews Title: Preoperative serum CA 72.4 as prognostic factor of recurrence and death, especially at TNM stage II, for colorectal cancer Authors: Daniel Ayude (d.ayude@czveterinaria.com) Francisco Javier Rodriguez-Berrocal (berrocal@uvigo.es) José Ayude (jayude@uvigo.es) Sonia Blanco-Prieto (soniabp@uvigo.es) Marta Vázquez-Cedeira (martavzc@usal.es) Lorena Vázquez-Iglesias (lorena.vazquez@uvigo.es) María Páez de la Cadena (mpaez@uvigo.es) Version: 2 Date: 5 October 2012 Author's response to reviews: see over María Páez de la Cadena Department of Biochemistry, Genetics and Immunology Facultad de Biología, Universidad de Vigo. 36310 Vigo. Spain. Phone: +34 986812571 Email: mpaez@uvigo.es Vigo, October 04th, 2012 Editor-in-Chief BMC Cancer Dear Editor, Hereby we are submitting the manuscript entitled: “Preoperative serum CA 72.4 as prognostic factor of recurrence and death, especially at TNM stage II, for colorectal cancer”, by Daniel Ayude, Francisco Javier Rodriguez Berrocal, José Ayude, Sonia Blanco-Prieto, Marta Vázquez-Cedeira, Lorena Vázquez-Iglesias and María Paez de la Cadena, to consider for publication in BMC Cancer. This work has demonstrated the prognostic value of CA 72.4 at stage II colorectal cancer that could improve the risk stratification of patients for the administration of adjuvant chemotherapy. We have added the approval of the study by an appropriate ethics committee in the Methods section of the manuscript. Sincerely, María Páez de la Cadena