Types of Neuroendocrine Tumors

Neuroendocrine tumors can originate from many different sites in the body. The most common types include:

– Gastrointestinal NETs (GI-NETs): These tumors start in the digestive tract and are the most common type of NET. Common sites include the small intestine, rectum, and stomach.

– Lung NETs: These NETs start in lung tissue such as the bronchi or elsewhere in the lungs. Types include typical and atypical carcinoid tumors.

– Pancreatic NETs: Also known as islet cell tumors or pancreatic Neuroendocrine Tumor Treatment, these NETs form in the pancreas. Subtypes include insulinomas and gastrinomas.

– Unknown Primary NETs: In some cases, a NET is found with no obvious primary site of origin after extensive testing. This means the original source remains unknown.

Staging Neuroendocrine Tumors

Staging a NET helps doctors determine the extent of disease spread from the primary site. The most widely used staging system is the ENETS staging system specific to neuroendocrine tumors:

– Stage I: The tumor is localized to the primary site without spread.

– Stage II: The tumor has spread locally to nearby tissues or organs.

– Stage III: There is regional lymph node involvement with or without local spread.

– Stage IV: The cancer has metastasized to distant lymph nodes, organs, or other parts of the body.

Surgery for Neuroendocrine Tumors

Surgical removal of the primary tumor through an operation is often the first treatment option considered, if feasible. The type of surgery depends on the tumor’s location and stage. Some common procedures include:

– Biopsy to confirm diagnosis and obtain tumor samples for analysis.

– Polypectomy to remove intestinal polyps.

– Resection/excision to remove the tumor with some surrounding tissue margins.

– Segmental/partial resection of the affected organ part.

– lymph node dissection to examine lymph nodes for cancer involvement.

Surgery aims to completely remove the tumor with minimal damage to the organs. It is often curative for early-stage localized NETs. Even for advanced NETs, debulking large tumors can relieve symptoms.

Systemic Neuroendocrine Tumor Therapy

For patients whose NETs cannot be fully removed surgically or have spread to distant sites, systemic therapies are needed. Common options include:

– Chemotherapy uses anti-cancer drugs to shrink tumors and destroy cancer cells. A few chemo drugs like cisplatin, 5-FU, and streptozocin have shown modest success against aggressive NETs. However, well-differentiated low-grade NETs usually do not respond as well.

– Somatostatin analogs (SSAs) help control symptoms by regulating hormone oversecretion from NETs. Drugs like octreotide and lanreotide bind to somatostatin receptors on tumor cells. They are the first treatment option for functional pancreatic NETs. SSAs may also help slow tumor growth.

– Targeted therapy uses drugs that target specific molecular abnormalities within cancer cells. Popular agents for advanced NETs include everolimus and sunitinib that block molecular pathways driving cancer progression.

– PRRT or peptide receptor radionuclide therapy utilizes radiolabeled somatostatin analogs to deliver radiation directly to NET cells expressing somatostatin receptors. This personalized therapy can induce remission in refractory NETs.

– Hepatic arterial embolization works for liver-dominant neuroendocrine metastases. It blocks the hepatic artery, cutting off the blood supply and oxygen/nutrients to cancer cells in the liver.

Managing Neuroendocrine Tumor Symptoms

Neuroendocrine tumors often secrete various hormones causing distinct clinical syndromes. Managing these functional symptoms is an important part of care:

– For carcinoid syndrome from serotonin-secreting tumors, preventative options like octreotide help reduce flushing and diarrhea.

– High blood sugar and diabetes resulting from insulinomas require monitoring blood glucose levels and possible insulin therapy.

– Gastrinomas which overproduce gastrin cause Zollinger-Ellison syndrome with severe ulcers requiring long-term antacids.

– Treatment with somatostatin analogs, everolimus, PRRT, or surgery control symptoms from VIPomas, glucagonomas and other rare tumors.

– Medications, celiac plexus or splanchnic nerve block help alleviate severe pain from non-functioning pancreatic neuroendocrine tumors.

*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it