Exploring the Link Between Cancer Genetics and PPSP

This study will be a retrospective, case-control study. There will be two groups of patients identified retrospectively: The first group will be patients who have been referred to the pain management team for persistent-post surgical pain following breast cancer treatment. The second group, will consist of patients who have been matched for age, procedure and time-lapsed since operation. These patients will not have persistent post-surgical pain. Archived paraffin-embedded tissue samples, that have previously been taken from these patients, will be required. Samples accessed will be from patients who have previously provided consent for their samples to be used for research purposes. Once appropriate samples have been identified by the tissue banks, all data will be pseudonymised. This will include details that patients have consented to providing for research purposes via the Pain Management Database, which has Trust (CCR 442) and Research Ethics Committee (REC 16/LO/1989) approval. Laboratory studies will then be conducted to A) investigate the underlying variations of the PIK3CA gene of tumours within the two cohorts of patients, B) investigate other genetic variations between these two groups and C) establish the key genetic and signalling pathway alterations between these two groups. The methods by which these investigations will be conducted will be by performing PIK3CA genomics, genetic profiling, next generation sequencing and finally immunohistochemistry for activation of signalling pathways. This study will analyse archived paraffin embedded tissue samples in a laboratory only. The anticipated time-scale for this project would be approximately one year.