Case report: Uncommon multiple metastases from occult breast cancer revealed by 68Ga-DOTATATE PET/CT

Abstract

Occult breast cancer is an uncommon type of breast cancer and its diagnosis is challenging. It is usually invisible on multiple imaging examines. Metastases to the rectum and inguinal lymph nodes from occult breast lobular cancer are even rarer. 68Ga-DOTA peptides can image neuroendocrine tumors by targeting specific somatostatin receptors. Besides, other tumors, including breast cancer, have been shown to express somatostatin receptors. In this case, we presented a 63-year-old woman who underwent both 18F-FDG and 68Ga-DOTATATE PET/CT due to a rectal polyp. An endoscopic excision biopsy confirmed metastatic carcinoma of suspected breast origin, but subsequent ultrasound and MRI showed no signs of malignancy in the breast and adnexa uteri. PET/CT showed obvious 68Ga-DOTATATE activity in bilateral axillary and right inguinal lymph nodes with mild 18F-FDG uptake. Final histopathology at the left axillary, right inguinal lymph nodes, and rectum indicated metastases from breast cancer while the origin remained radiologically occult. Additionally, one uterine fibroids was found with positive uptake of 68Ga-DOTATATE and negative uptake of 18F-FDG. This case suggested that 68Ga-DOTATAE PET/CT may be an effective supplement in diagnosing OBC lymph node metastases with mild 18F-FDG uptake, and it may provide a new technology for the clinical diagnosis of occult breast cancer.

Metastatic Esophageal Adenocarcinoma Showing 68Ga-DOTATATE Uptake

“…5 Nevertheless, although 68 Ga-DOTATATE uptake has been described in many nonneuroendocrine tumors, no case of esophageal adenocarcinoma displaying 68 Ga-DOTATATE uptake has been reported before. [6][7][8][9] This particular case of metastatic esophageal adenocarcinoma showing 68 Ga-DOTATATE uptake highlights the potential of 68 Ga-DOTATATE PET/CT in imaging nonneuroendocrine tumors.…”

“…The presence of a significant number of somatostatin ( D ) cells in the columnar epithelium of the stomach and the association of Barrett esophagus as a precursor lesion in the majority of esophageal adenocarcinomas are considered to explain this SSTR expression 5 . Nevertheless, although 68 Ga-DOTATATE uptake has been described in many nonneuroendocrine tumors, no case of esophageal adenocarcinoma displaying 68 Ga-DOTATATE uptake has been reported before 6–9 . This particular case of metastatic esophageal adenocarcinoma showing 68 Ga-DOTATATE uptake highlights the potential of 68 Ga-DOTATATE PET/CT in imaging nonneuroendocrine tumors.…”