[A case of acute appendicitis which occurred during chemotherapy for breast cancer]

The patient was a 66-year-old woman with left breast cancer who underwent left segmental mastectomy with sentinel lymph node biopsy. The histopathological diagnosis was estrogen receptor-positive (ER+), progesterone receptor-positive( PgR+), human epidermal growth factor receptor-2-equivocal( HER2()2+)( with no HER2 gene amplification by fluorescence in-situ hybridization analysis) invasive ductal carcinoma (scirrhous carcinoma) with Ki-67 expression of less than 10% (pathological T1c, N0, M0, stage I). The patient requested chemotherapy, and 4 cycles of docetaxel plus cyclophosphamide (TC) were scheduled. Fever and epigastric pain developed on day 13 of cycle 2. On day 22, the patient was examined before the third cycle of TC, and right lower abdominal pain was reported. Computed tomography revealed appendicitis and an intraperitoneal abscess. She was admitted to the hospital and underwent partial ileocecal resection. The patient was discharged on the 12th postoperative day with no further complications. Acute abdomen during chemotherapy for malignant tumors has been reported sporadically in patients with leukemia. A diagnosis of acute abdomen in patients undergoing cancer treatment requires careful assessment of gastrointestinal symptoms such as nausea and vomiting during chemotherapy, fever associated with granulocytopenia, and findings indicative of local inflammation. The patient in this case recovered uneventfully because imaging studies and surgery were performed promptly after presentation.