How to prioritize treatment in dual malignancy: A case report of patient with non-Hodgkin lymphoma and breast cancer.

INTRODUCTION: Clinicians often encounter dilemma upon treating multiple primary malignancies. CASE PRESENTATION: We report a case of a female patient, 72, complained of a lump under her left eye since January 2019. Patient was diagnosed with infiltrating ductal carcinoma grade III of the right breast in June 2018 with ER+, PR+, and HER2-, treated with hormonal treatment. Histopathology examination of the lump revealed Non Hodgkin Lymphoma (NHL), B cell type, high grade. Patients received rituximab, cyclophosphamide, epirubicin, vincristin, and prednisone (RHCOP) for 6 cycles to overcome lymphoma then received hormonal therapy afterwards. CLINICAL DISCUSSION: According to earlier published case reports, it's advised to start hormonal therapy after RHCOP. The survival time was 21 months (5.1-114.7 months) with 5-year overall survival 29. CONCLUSION: Unfortunately, we could not have a follow-up on the patient after finishing 6 cycles of RHCOP due to the COVID-19 pandemic situation.