Treatment of oncological patients must be based upon multidisciplinary approach, and takes place in specialized oncological centers. By the end of a specific oncological treatment further follow-up is being managed mostly by the oncologists, but the role of the general practitioners becomes more important every day and therefore should be precisely defined. Nowadays, most of the existing follow-up guidelines are not being based on prospective studies, yet on the expert’s opinion of a precise oncological center or specialists. The aim of the Croatian Society of Medical Oncology (CSMO) with these recommendations is to standardize and rationalize the diagnostic procedures’ algorithm in follow–up of oncological patients after primary treatment, in patients with planocellular head and neck cancer, oesophageal cancer, gastric cancer and colorectal cancer.