Table 1.

Molecular profiling studies revealing MEN1 alterations in pNETs.

Technique	Reference	Key Findings
Exome/genome sequencing	[24]	Somatic MEN1 mutations in 44.1% of 68 sporadic pNETs. MEN1 mutations correlated with poor patient survival.
	[23]	Somatic MEN1 mutations in 41% of 102 primary pNETs. Abnormal telomere length observed in MEN1-mutated tumors.
	[39]	In total, 26% of 57 sporadic well differentiated pNETs had recurrent LOH of 10 specific chromosomes and biallelic MEN1 inactivation. Another 40% had chromosome 11 LOH and biallelic MEN1 inactivation. The first patient group had worse clinical outcomes compared to the second.
	[40]	MEN1 mutations in 43% of 65 pNETs.
	[43]	Somatic MEN1 mutations in 56% of 80 patient pNETs. In total, 1 of 17 patients carried a germline MEN1 mutation.
Allelotyping/LOH analysis	[31]	Loss of chromosomal segment 11q (where MEN1 is located) in >60% cases.
	[34]	LOH of 11q13 in 70% and MEN1 mutations in 27% of 11 advanced pNETs (9 NF and 2 glucagonomas).
	[29]	MEN1 mutatons in 6 (mostly pNETs) of 43 sporadic GEPNETs.
	[37]	MEN1 allelic deletions in 93% of gastrinomas and 50% of 12 insulinomas; mutations in 33% gastrinomas and 17% insulinomas.
Microarray	[35]	Consensus cluster analysis of microarray results showed clustering of 5 out of 9 sporadic NF-pNETs with MEN1-associated familial pNETs. In total, 4 of those 5 sporadic pNETs had MEN1 LOH.