Answer: C. Recommended treatment for a high-grade neuroendocrine tumor of unknown primary site is platinum-based chemotherapy.
This patient has high-grade poorly differentiated neuroendocrine tumors arising from an unknown primary site. These tumors often respond rapidly to systemic platinum-based chemotherapy, such as the regimens used to treat small cell lung cancer. Small cell lung cancer is the most likely primary site for the infection even though it is not seen on the CT scan of the chest.
These regimens may lead to substantial side effects, however, the potential for clinical benefit, including improved symptom control and prolonged survival, is significant. The bone metastases are also likely to respond to this chemotherapy regimen.
Hepatic artery embolization is a locoregional therapy that is often used to treat patients with low-grade neuroendocrine tumors, but this technique is not effective for treating patients with high-grade neuroendocrine tumors. Therefore this would not provide therapy for the bone metastases.
Octreotide is useful for treating patients with low-grade neuroendocrine tumors and specifically for managing hormonal symptoms caused by hormonally functional tumors, but it is not effective for treating patients with high-grade neuroendocrine tumors. Therefore, it would not likely be effective in this patient.
Starting radiation therapy for bone metastases is inappropriate because it would delay chemotherapy for the visceral metastases, which are clinically more important. Also, chemotherapy may also treat the bone metastases.
Radiofrequency ablation is useful for treating patients with a limited number of small metastases of low-grade neuroendocrine tumors but would not be appropriate for treating patients with high-grade neuroendocrine tumors or for managing patients with bulky liver metastases.
Reference:
Reidy DL, Tang LH, Saltz LB. Treatment of advanced disease in patients with well-differentiated neuroendocrine tumors. Nat Clin Pract Oncol. 2009 Mar;6(3):143-52. PMID: 19190591