Previously undiagnosed neuroendocrine tumour mimicking breast cancer metastasis to the orbit

Research output: Contribution to journalArticlepeer-review

1 Scopus citations


Metastatic neuroendocrine neoplasms to the breast are rare and histopathologic overlap with mammary carcinomas has led to misdiagnosis. We present a case of a middle-aged woman with diplopia and a right medial rectus mass. Metastatic breast cancer was initially suspected based on a history of invasive ductal carcinoma. Detailed immunohistochemistry of the orbital biopsy, gallium-68 dotatate positron emission tomography-CT, and reevaluation of her prior breast specimen, demonstrated that her initial breast carcinoma diagnosis was in error and she was ultimately diagnosed with a previously unknown gastrointestinal neuroendocrine tumour metastatic to both the orbit and breast. This case highlights the challenges of differentiating between metastatic neuroendocrine tumours and invasive mammary carcinomas with neuroendocrine differentiation both in the breast and in the orbit. It is important to recognise the overlap so that a primary neuroendocrine neoplasm is not missed, or treatment significantly delayed.

Original languageEnglish (US)
Article numbere234629
JournalBMJ Case Reports
Issue number5
StatePublished - May 20 2020


  • oncology
  • ophthalmology
  • pathology

ASJC Scopus subject areas

  • Medicine(all)


Dive into the research topics of 'Previously undiagnosed neuroendocrine tumour mimicking breast cancer metastasis to the orbit'. Together they form a unique fingerprint.

Cite this