Breast cancer combined with contralateral neck lymph node metastasis: a case report

BACKGROUND: Contralateral neck lymph node metastasis is rare in primary breast cancer. Its clinical staging and treatment principles lack authoritative guidelines. A case of a 30-year-old breast cancer patient with contralateral neck lymph node metastasis is presented. The clinical treatment is discussed in combination with current research. CASE PRESENTATION: A 30-year-old woman presented with a right breast mass for 5 months and left neck lymph node enlargement for 5 days. Mammography showed a 33 mm*14.3 mm mass in the inner quadrant of the right breast. The ultrasound showed several hypoechoic nodules on the left side of the neck. Rapid intraoperative pathological examination diagnosed a right breast malignant tumor and poorly differentiated carcinoma of the left cervical lymph nodes. Then, right mastectomy was performed immediately. The patient was scheduled to undergo chemotherapy, molecular targeted therapy, radiotherapy and endocrine therapy after the operation. The long-term efficacy remains to be seen. CONCLUSION: The infrequent presentation of breast cancer with metastasis to the contralateral neck lymph node can be challenging for standard therapies.