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detected at the age of 42 years. Multiglandular parathyroid involvement is character-
istic of MEN1 syndrome either as parathyroid adenoma or hyperplasia or as a combi-
nation of both. Preoperative imaging is of limited value as the sensitivity to localize
multiglandular disease by any imaging modality, whether ultrasonography or sesta-
mibi scan, is only 55–65 % as compared to 80–95 % for localization of single-gland
disease. This is because ultrasonography cannot detect small-sized adenomas/hyper-
plasic gland, whereas localization of abnormal gland by sestamibi scan depends on
mitochondrial content of the abnormal gland which may be variable in multiglandular
disease. Therefore, patients with MEN1 should be subjected for bilateral neck explo-
ration irrespective of localization. Further, 3.5 gland excision is recommended to pre-
vent the recurrence of disease as the presence of multiglandular disease may be
synchronous or metachronous. In the index patient, ultrasonography did not localize
any abnormal gland, whereas sestamibi scan localized three abnormal parathyroid
glands. On bilateral neck exploration, three abnormal parathyroid glands were identi-
fied and excised accordingly. Like other neoplasias, parathyroid carcinoma is rare in
MEN1 syndrome. Approximately 40 % of patients with MEN1 syndrome have gastri-
nomas, and 60 % of these gastrinomas are present in the duodenum, while the rest are
present in the pancreas. The index patient had increased basal acid output and hyper-
gastrinemia, and there were two hypodense lesions in the head and body of the pan-
creas suggestive of gastrinomas. Surgical enucleation of these lesions resulted in
normalization of serum gastrin levels. Bilateral symmetrical/asymmetrical nonfunc-
tional adrenomegaly is the characteristic feature of MEN1 syndrome and has been
reported in approximately 40 % of patients. However, single or multiple adenomas
have also been reported, but only 10 % of patients with adrenal lesions have hormonal
hypersecretion. Adrenal lesions >4 cm require surgical excision. Occurrence of mul-
tiple endocrine neoplasia in a same patient, either synchronous or metachronous, has
been attributed to loss-of-function of MEN1 gene, which is a tumor suppressor gene.
In our patient, duplication of C1546 gene in exon 10 and frame-shift mutation at
P-Arg 516 was found, and it was consistent with MEN1 syndrome.
11.3 Clinical Rounds
- What is multiple endocrine neoplasia?
Multiple endocrine neoplasia (MEN) is a heterogeneous group of autosomal
dominant inherited disorder characterized by the presence of tumors involving
≥2 endocrine organs, either synchronous or metachronous, in a same patient.
The clinical manifestations of MEN syndrome depend on the involvement of
endocrine organs and the hormone/s secreted by them.- What are the types of MEN syndrome?
Multiple endocrine neoplasia is conventionally classified into type 1 and type 2
MEN syndrome. Type 2 is further subclassified into 2A and 2B (also called as11 Multiple Endocrine Neoplasia