PT  - JOURNAL ARTICLE
AU  - Rubio, Carlos A
AU  - Schmidt, Peter T
TI  - Asymmetric crypt fission in sessile serrated lesions
AID  - 10.1136/jclinpath-2020-207008
DP  - 2021 Nov 01
TA  - Journal of Clinical Pathology
PG  - 712--717
VI  - 74
IP  - 11
4099  - http://jcp.bmj.com/content/74/11/712.short
4100  - http://jcp.bmj.com/content/74/11/712.full
SO  - J Clin Pathol2021 Nov 01; 74
AB  - Objective Sessile serrated lesions without dysplasia (SSL-ND) are epitomised by dilated crypts with epithelial serrations and architectural distortions portraying boot-shapes, L-shapes or inverted-T shapes. Recently, crypts in asymmetric fission were detected in SSL-ND. The purpose was to assess the frequency of crypts in asymmetric fission in a cohort of SSL-ND.Methods The frequency of crypts in fission was assessed in 60 SSL-ND, the distribution of cell proliferation in 48 SSL-ND and the expression of maspin, a tumour-suppressor protein, in 29 SSL-ND.Results Out of the 60 SSL-ND, 40 (66.7%) showed crypts in fission: 39 (65%) SSL-ND had crypts in asymmetric fission and one SSL-ND (1.7%), in symmetric fission (p<0.05). Of 1495 crypts recorded in the 60 SSL-ND, 73 (4.9%) were in asymmetric fission but only one (0.06%), in symmetric fission (p<0.05). Out of the 48 Ki67-immunostained SSL-ND,15 (31%) showed randomly distributed proliferating cell-domains. All 29 SSL-ND revealed maspin-upregulation (including crypts in asymmetric and symmetric fission). In contrast, the normal colon mucosa showed occasional single crypts in symmetric fission, proliferating cell-domains limited to the lower thirds of the crypts, absence of crypts in asymmetric fission and remained maspin negative.Conclusions SSL-ND thrive with crypts in asymmetric fission displaying randomly distributed proliferating cell-domains and maspin-upregulation. These histo-biological aberrations disclose pathological cryptogenesis and suggest possibly unfolding somatic mutations in SSL-ND. The present findings may open new vistas on the parameters pertinent to the susceptibility of SSL-ND to develop dysplasia and carcinoma.Data are available upon reasonable request. All data relevant to the study are included in the article. The present findings highlight a previously unreported structural histological change in sessile serrated lesions without dysplasia, namely the occurrence of asymmetric crypts in fission.