Malignant fibrous histiocytoma of the axilla with breast cancer: A case report

BACKGROUND: Multiple primary malignant neoplasms refer to multiple tumors with different origins. They may be synchronous or metachronous. The incidence is 0.73%– 11.7%. Synchronous cases of breast cancer with sarcoma are rare. CASE SUMMARY: Here, we report a 78-year-old female patient admitted to hospital after accidental discovery of a left axillary mass. Preoperative examination revealed a breast mass. Pathology showed left breast cancer and left axillary sarcoma. The patient underwent surgery, endocrine therapy and radiotherapy. She has been followed up for 1 year, and no local recurrence or distant metastasis was observed. CONCLUSION: Attention should be paid to multiple primary malignant neoplasms, not limited to the current diagnosis and analysis, avoiding missed diagnosis and misdiagnosis.