Multiple Endocrine Neoplasm (MEN) is a rare, complex and familial disease. There are MEN syndromes are inherited in an autosomal dominant fashion with high penetrance. The variations in the RET gene play an important role in the MEN syndromes. Recent advances in diagnosis, treatment and genetic study of patients with MEN in Korean are reviewed.

There were 79 cases and 20 families with MEN syndromes in Korea which based on my experiences and 27 published papers. According to subtypes, there were classified and analyzed.

Mean age was 37.9±11.5 years old. Sex ratio was 1:2.6. There were 7 families and 23 cases with MEN type I in Korean. The clinical characteristics of MEN I in Korean are mostly not different from the previous reports except older age (mean=43.2 old-year) at diagnosis. The frequency of the MEN I germ-line mutation in Korean MEN I (80%) families was similar to those reported previously. There were 13 families and 52 cases with MEN type II A in Korean. Three-quarters (9/12) of the Korean patients with MEN IIa had RET mutations on codon 634 of exon 11 (4 patients, C634; 4 patients, C634Y; 1 patient, C634W), but a quarter (3/12) had mutations on codon 618 of exon 10 (2 patients, C618R; 1 patient, C618S). A small medullary carcinoma in a patient of MEN type II A family was detected by genetic mutation screening in SMC. MEN IIb was reported only 4 cases. A case showed a codon 918 mutation (M918T) at exon 16 of RET proto-oncogene.

Multiple endocrine neoplasia is rare hereditary cancer syndromes expressing a variety of tumors. With understanding of the molecular and clinical pathology of MEN syndromes, genetic screening is now feasible, and treatments have become more individualized based on genetic information of Korean.