Pneumocystis jirovecii Pneumonia Infection in Breast Cancer Receiving Dose-dense Chemotherapy: A Case Report and Literature Review

We herein report 3 cases of breast cancer who developed Pneumocystis Jirovecii Pneumonia during dose-dense chemotherapy. The patients developed fever, fatigue, and cough on the 4th to 5th cycle of chemotherapy. Chest computed tomography (CT) scan showed ground-glass opacities, later on confirmed PCP as bronchoalveolar lavage (BAL) was performed. They were treated with Trimethoprim-Sulfamethoxazole (TMP-SMX) for 3 weeks, with clinical improvement. The first case was able to complete subsequent cycles of chemotherapy with TMP-SMX prophylaxis. The second case omitted the remaining cycles of chemotherapy and proceeded with adjuvant hormonal and radiotherapy. The third case also discontinued subsequent cycles and proceeded with surgery. All 3 cases didn’t developed complications nor recurrence of infection on their subsequent treatments. Clinicians must be vigilant in recognizing those at risk for PCP especially among cancer patients undergoing dose-dense chemotherapy. Moreover, as the infection is life-threatening, early treatment must be initiated to prevent serious complications. Prophylactic antibiotic must be considered if there is a high-risk for recurrence of infection, thus preventing delay in surgery or adjuvant therapies.