Table 3. Summary of main findings.

ILC: invasive lobular carcinoma; HIPEC: hyperthermic intraperitoneal chemotherapy

Key findings

ILC, high tumor grade and loco-regional involvement are associated with peritoneal metastases.

HER2-enriched, luminal B and basal-like tumors have a greater propensity to spread to the peritoneum.

Findings in othotopic xenografts suggest a role for somatic loss of p53 and E-cadherin in the development of breast cancer peritoneal metastases.

There is variability in the definition and diagnostic criteria used for breast cancer peritoneal metastases including the presence of ascites, positive ascites cytology and peritoneal lesions on CT.

Studies evaluating the role of surgery are mainly small and retrospective.

Cytoreduction and HIPEC demonstrated encouraging results in small cohorts. Larger and more robust studies are needed in order to determine their impact on breast cancer-specific survival.

Studies suggest a role for palliative cytoreductive surgery in selected patients when there is minimal or no residual disease.