High SUVmax on PET-CT in breast lesions: two intraductal papillomas mimicking malignancy – a two-case report

Introduction and importance: PET‑CT SUVmax is often used to triage breast lesions, but benign entities can show high FDG uptake and mimic malignancy. Case presentation: We describe two women (78 and 45 years old) presenting with pathological nipple discharge. PET‑CT suggested malignancy with high SUVmax (6.1 and 6.3); however, histopathology confirmed intraductal papilloma in both. We also reviewed seven additional patients with breast cancer who underwent preoperative PET‑CT. Clinical discussion: In this nine-patient series (seven cancers, two papillomas), SUVmax values overlapped between malignant and benign lesions. A Mann–Whitney U test showed no significant difference ( P > 0.05), underscoring that SUVmax alone is insufficient to discriminate cancer from intraductal papilloma and should be interpreted with morphology and, where appropriate, pathology. Conclusion: Do not rely on SUVmax as a key stand-alone criterion to differentiate breast cancer from intraductal papilloma; a multimodal approach is recommended to avoid misdiagnosis.