World Endometriosis Research Foundation Endometriosis Phenome and Biobanking Harmonisation Project: IV. Tissue collection, processing, and storage in endometriosis research.

OBJECTIVE: To harmonize standard operating procedures (SOPs) and standardize the recording of associated data for collection, processing, and storage of human tissues relevant to endometriosis.

DESIGN: An international collaboration involving 34 clinical/academic centers and three industry collaborators from 16 countries on five continents.

SETTING: In 2013, two workshops were conducted followed by global consultation, bringing together 54 leaders in endometriosis research and sample processing from around the world.

PATIENT(S): None.

INTERVENTION(S): Consensus SOPs were based on: 1) systematic comparison of SOPs from 24 global centers collecting tissue samples from women with and without endometriosis on a medium or large scale (publication on >100 cases); 2) literature evidence where available, or consultation with laboratory experts otherwise; and 3) several global consultation rounds.

MAIN OUTCOME MEASURE(S): Standard recommended and minimum required SOPs for tissue collection, processing, and storage in endometriosis research.

RESULT(S): We developed "recommended standard" and "minimum required" SOPs for the collection, processing, and storage of ectopic and eutopic endometrium, peritoneum, and myometrium, and a biospecimen data collection form necessary for interpretation of sample-derived results.

CONCLUSION(S): The EPHect SOPs allow endometriosis research centers to decrease variability in tissue-based results, facilitating between-center comparisons and collaborations. The procedures are also relevant to research into other gynecologic conditions involving endometrium, myometrium, and peritoneum. The consensus SOPs are based on the best available evidence; areas with limited evidence are identified as requiring further pilot studies. The SOPs will be reviewed based on investigator feedback and through systematic triannual follow-up. Updated versions will be made available at: http://endometriosisfoundation.org/ephect.