The clinicopathological features of breast cancer in Peutz-Jeghers syndrome: results from an international survey.

Background: Female patients with Peutz-Jeghers syndrome (PJS) have an increased risk of breast cancer (BrCa), and surveillance is recommended. However, clinicopathological features of their tumors and prognosis are lacking. To facilitate more precise future guideline development, we evaluated these data.

Methods: We conducted an international survey for InSiGHT members to collect retrospective data on PJS patients with diagnosed breast cancer.

Results: We received 23 responses, including three centers with data on BrCa patients. All reported BrCa patients were female. In total, the cohort comprised 27 patients with 34 BrCa (five bilateral synchronous, one bilateral metachronous, and one metachronous unilateral tumours). The median age at first cancer diagnosis was 45 years (range 26-67). Most cancers were ductal carcinoma, either invasive (13) or in situ (DCIS; 19). TNM staging for invasive cancer was available in thirteen cases, of which nine were T1N0M0. Among tumors with histological reports, 14/15 were oestrogen receptor positive, 8/15 were progesterone receptor positive, and 4/15 were HER2 positive. There were no triple negative breast cancers. Twenty-five patients had follow-up data, comprising 229 patient years. Eleven patients had died of any cause during follow-up. Survival at 5 years was 73%.

Conclusion: Overall, breast cancers that occur in this PJS population seem to have favorable characteristics and prognosis. These data will help inform discussions about risk management in patients with PJS. Further research is needed to better understand lifetime risk, the optimal surveillance modality and its outcomes.