Management strategies in Lynch syndrome and familial adenomatous polyposis: a national healthcare survey in Japan.

Lynch syndrome (LS) and familial adenomatous polyposis (FAP) are major sources of hereditary colorectal cancer (CRC) and are associated with other malignancies. There is some heterogeneity in management strategies in Japan. We undertook a survey of management of hereditary CRC in hospitals that are members of the Japan Society of Colorectal Cancer Research. One hundred and ninety departments responded, of which 127 were from designated cancer care hospitals (DCCHs) according to the Japanese government. There were 25 488 operations for CRC in these departments in 2015. The DCCHs performed better with regard to usage of Japan Society of Colorectal Cancer Research guidelines, referring new CRC patients for LS screening, and having in-house genetic counselors and knowledge of treatment for LS. There were 174 patients diagnosed with LS and 602 undergoing follow-up in 2011-2015, which is fewer than the number expected from CRC operations in 2015. These numbers were not affected by whether the institution was a DCCH. Universal screening for LS was carried out in 8% of the departments. In contrast, 541 patients were diagnosed with FAP and 273 received preventive proctocolectomy/colectomy in 2011-2015. The DCCH departments undertook more surgery than non-DCCH departments, although most of the management, including surgical procedures and use of non-steroidal anti-inflammatory drugs, was similar. Management of desmoid tumor in the abdominal cavity differed according to the number of patients treated. In conclusion, there was heterogeneity in management of LS but not FAP. Most patients with LS may be overlooked and universal screening for LS is not common in Japan.