Related Experiment Video
Updated: Apr 8, 2026
Gene Regulation and Targeted Therapy in Gastric Cancer Peritoneal Metastasis: Radiological Findings from Dual Energy CT and PET/CT
Published on: January 22, 2018
A Unique Case of Diffuse Metastatic Neuroendocrine Cancer with Subcutaneous Nodules on (18)F-Fluorodeoxyglucose
Mickaila J Johnston1, Archana Sachedina2, James E McDonald2
1Department of Radiology, Nuclear Medicine Division, Naval Medical Center, San Diego, California, USA.
Abstract:
Neuroendocrine tumors (NETs) account for 8-10% of cases of carcinomas of unknown primary. Most of these cases are poorly differentiated with metastatic disease at the time of diagnosis. However, cutaneous metastatic presentation is rare. We present an interesting case of a 74-year-old woman presenting with cutaneous metastatic involvement from high grade poorly differentiated NET of unknown origin. She was referred to us with a diagnosis of lymphoma. (18)F-fluorodeoxyglucose positron emission tomography/computer assisted tomography imaging at our institution offered a differential diagnosis, including neuroendocrine cancer. Repeat skin lesion biopsy demonstrated "non-Merkel cell" carcinoma, favoring metastatic high-grade neuroendocrine carcinoma.
Insights
Cutaneous metastatic neuroendocrine tumors (NETs) are rare, often presenting as lymphoma. This case highlights NETs of unknown origin presenting with skin metastases, emphasizing diagnostic challenges.
Area of Science:
- Oncology
- Dermatology
- Nuclear Medicine
Background:
- Neuroendocrine tumors (NETs) represent 8-10% of carcinomas of unknown primary, frequently diagnosed at advanced stages.
- Metastatic disease is common in poorly differentiated NETs, but cutaneous involvement is an infrequent presentation.
Observation:
- A 74-year-old woman initially diagnosed with lymphoma presented with skin lesions.
- Imaging with (18)F-fluorodeoxyglucose positron emission tomography/computer assisted tomography suggested neuroendocrine cancer.
- Repeat skin biopsy confirmed metastatic high-grade neuroendocrine carcinoma, not otherwise specified.
Findings:
- The case illustrates a rare instance of cutaneous metastasis from a high-grade, poorly differentiated neuroendocrine tumor of unknown primary origin.
- Diagnostic confusion with lymphoma highlights the importance of considering NETs in atypical presentations.
Implications:
- This case underscores the diagnostic challenges posed by rare cutaneous NET metastases.
- It emphasizes the utility of advanced imaging and repeat biopsies in identifying neuroendocrine malignancies.
- Increased awareness may improve early diagnosis and management of such rare presentations.
