Nanocarbon localization and 68Ga-DOTA-NOC scan in the diagnosis and management of neuroendocrine tumors (NETs): A case report.

Introduction: Reports of rectal neuroendocrine tumor (R-NET) are relatively rare. There is a lack of experience in how to accurately locate and resect metastatic lateral lymph nodes.

Case presentation: We present a challenging case. The patient was diagnosed with rectal neuroendocrine tumor. After endoscopic submucosal dissection (ESD), this patient came to hospital for reexamination. The imaging results indicated the presence of left lateral lymph node metastasis, so total mesorectal excision (TME) plus lateral lymph node dissection(LLND) was performed. One year later, PET-CT was reexamined again, using a contrast agent targeted at somatostatin receptor. The result showed residual metastatic lymph nodes. We used nanocarbon combined with coil to accurately locate the metastatic lymph nodes and finally successfully resected the lymph node. The patient recovered and was discharged 5 days after the operation.

Discussion: Surgery is the most effective method for treating rectal neuroendocrine tumors. However, it is still challenging to accurately detect and locate metastatic lymph nodes after surgery. 68Ga-DOTA-NOC is a special contrast agent that targets somatostatin receptors, and somatostatin receptors are highly expressed in NETs. Using it can clearly trace whether the lateral lymph nodes are metastasized. Nanocarbon localization has been used for the localization of various tumors. We combined it with coils and effectively located the metastatic lymph nodes. This localization method has great potential.

Conclusion: Surgical resection is the most effective way to treat rectal neuroendocrine tumors. Nanocarbon combined with coils can effectively locate metastatic lymph nodes, which is helpful for accurate resection later. And 68Ga-DOTA-NOC can assist in detection of metastatic lymph nodes.