International Endocervical Adenocarcinoma Criteria and Classification (IECC): correlation with adverse clinicopathological features and patient outcome

Aims The International Endocervical Adenocarcinoma Criteria and Classification (IECC) was recently proposed as an improved method for categorising endocervical adenocarcinoma (EA) into human papillomavirus (HPV)-associated adenocarcinomas (HPVAs) and non-HPV-associated adenocarcinomas (NHPVAs). Such categorisation correlates with patient age and tumour size; however, its association with patient outcome remains to be established. Methods Institutional cases of EA with histological material available were selected. Three gynaecological pathologists independently classified all tumours according to the IECC with consensus review used when necessary. Clinicopathologic variables were recorded for each case. Results Of a total of 87 EAs, 71 (82%) were classified as HPVA and 16 (18%) as NHPVA. Among HPVA, most were usual type (51/71, 72%) followed by mucinous not otherwise specified (10/71, 14%) and invasive stratified mucin-producing carcinoma (ISMC, 8/71, 11%). Most NHPVAs were of gastric type (12/16, 71%) followed by clear cell and mesonephric (two each, 12%). Compared with HPVAs, NHPVAs were significantly associated with older age (p<0.001), larger horizontal extent (p=0.013), greater depth of invasion (p=0.003), lymphovascular space invasion (p<0.001), advanced stage (p<0.001) and invasive pattern C (p<0.001). On univariate analysis, worse disease-free survival (DFS) and disease-specific survival (DSS) correlated with NHPVA group. Among the HPVA subtypes, ISMC showed worse DFS and DSS compared with other HPVA types. Conclusions The simple morphological approach of the IECC appears to be prognostically valuable. NHPVA (in particular gastric type) and ISMC (a recently recognised subset of HPVA) have an adverse outcome and their recognition following the IECC is important. We provide further evidence to replace the current WHO classification with the IECC.