Perineural invasion as a prognostic marker in breast cancer: a systematic literature review

• Grant number: 25/09747-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2025
• End date: June 30, 2026
• Field of knowledge: Biological Sciences - Morphology - Histology
• Principal Investigator: Sílvio Roberto Consonni
• Grantee: Bruno Sodré Serra Antunes
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Perineural invasion (PNI) is a mechanism of tumor dissemination characterized by the infiltration of neoplastic cells along peripheral nerves, frequently associated with unfavorable clinical outcomes in several types of cancer. Although well established in neoplasms such as prostate and pancreas, the prognostic relevance of PNI in breast cancer is still unclear. Therefore, this project proposes, in an unprecedented way to our knowledge, a systematic review of the literature with the objective of identifying and critically synthesizing the available evidence on the association between the presence of PNI and prognosis in patients with invasive breast cancer. The methodology will follow the PRISMA guidelines and the protocol will be registered on the PROSPERO platform. Searches will be conducted in PubMed, EMBASE, Scopus and Web of Science databases. Observational and experimental studies in English that evaluate the presence of PNI in breast cancer and report clinical outcomes, such as overall, disease-free or recurrence survival, will be included. Two independent reviewers will perform screening, data extraction and bias risk assessment using validated instruments. Ultimately, the aim is to consolidate the available knowledge and clarify whether PNI can be considered an independent prognostic marker in breast cancer. (AU)