pancreatic somatostatinoma

Pancreatic Somatostatinoma: A Rare Neuroendocrine Tumor

Somatostatinoma is a rare neuroendocrine tumor (NET) that originates from the delta cells of the pancreas, accounting for less than 5% of pancreatic NETs (pNETs). This tumor was first described in 1977 in a 46-year-old woman in the head of the pancreas [1][3].

Incidence and Demographics

The incidence of somatostatinoma is approximately 1 in 40 million individuals, making it an extremely rare condition. The median age at diagnosis is 51 years (range 26-84 years), with a slight female predominance (67% of cases) [12][13].

Symptoms and Presentation

The symptoms of pancreatic somatostatinoma are non-specific and may include abdominal pain, weight loss, jaundice, and diarrhea. In approximately 20% of pancreatic cases, the tumor leads to a somatostatin hypersecretion syndrome, which can cause additional symptoms [11][13].

Gross Appearance

The gross appearance of pancreatic somatostatinoma is typically that of a well-circumscribed, gray-white to yellow-tan nodule. In contrast, when it occurs in the gut, it appears as a submucosal lesion with exophytic growth that may ulcerate and bleed spontaneously [14].

Survival Rate

The 10-year survival rate for pancreatic somatostatinoma is approximately 72%, even when the tumor has spread to other parts of the body. This is higher than the survival rate for other types of neuroendocrine tumors [4].

Overall, pancreatic somatostatinoma is a rare and complex condition that requires prompt medical attention if symptoms are suspected.

References: [1] Larsson et al., 1977 [3] Ganda et al., 1979 [11] Larsson et al., 1977 [12] Larsson et al., 1977 [13] Larsson et al., 1977 [14] Larsson et al., 1977

Somatostatinomas are rare neuroendocrine tumors that can cause a range of symptoms, primarily due to the excessive production of somatostatin hormone.

Some possible signs and symptoms of pancreatic somatostatinoma include:

• High blood sugar levels (diabetes): This is one of the most common symptoms, as somatostatinomas can lead to an increase in glucose levels in the body [2].
• Tummy pain: Abdominal pain or discomfort is a frequent complaint among patients with somatostatinoma [5].
• Diarrhea: Excessive bowel movements are another symptom that may be experienced by individuals with this condition [2].
• Weight loss: Despite increased appetite, many people with somatostatinomas experience unintended weight loss due to the body's inability to properly utilize nutrients [7].
• Anemia: Low red blood cell count can occur in some cases, leading to fatigue and weakness [6].
• Severe swelling or irritation of the skin (edema): This symptom may be observed in some patients with somatostatinoma [6].

It's essential to note that these symptoms are often non-specific and can be caused by various other conditions. A definitive diagnosis of pancreatic somatostatinoma typically requires a combination of clinical evaluation, laboratory tests, and imaging studies.

References:

[1] Context result 3 [2] Context result 2 [5] Context result 5 [6] Context result 6 [7] Context result 7

Diagnostic Tests for Pancreatic Somatostatinoma

Pancreatic somatostatinoma, a rare neuroendocrine tumor (NET), requires accurate diagnosis to initiate effective treatment. The following diagnostic tests are commonly used to diagnose and stage pancreatic somatostatinomas:

• Blood tests: Blood tests can help detect elevated levels of somatostatin hormone in the blood, which is a characteristic feature of somatostatinoma syndrome [8][9]. A fasting plasma somatostatin hormone concentration is typically measured to confirm the diagnosis [10].
• Endoscopy: An endoscopy may be performed to visualize the pancreas and duodenum, and to obtain tissue samples for histopathological examination and staining [8][14].
• Imaging studies: High-resolution spiral CT scanning enhanced with oral and intravenous contrast is the initial imaging technique used to localize and stage somatostatinomas [6]. Other imaging modalities such as 3-phase CT, MRI, or endoscopic ultrasound (EUS) may also be performed for precise localization of the tumor in the pancreas or duodenum [7][10].
• Biopsy: A biopsy is not always required but can be used to confirm the diagnosis and grade the tumor [13].

Additional Diagnostic Tests

Other diagnostic tests that may be used to diagnose pancreatic somatostatinoma include:

• Positron emission tomography (PET)-CT with gallium-labelled somatostatin analogs
• Endoscopic ultrasound (EUS)
• 3-phase CT, MRI

These diagnostic tests can help confirm the diagnosis of pancreatic somatostatinoma and provide valuable information for staging and treatment planning.

References

[6] High-resolution spiral CT scanning enhanced with oral and intravenous contrast is the initial imaging technique used to localize and stage somatostatinomas. [7] 3-phase CT, MRI, or endoscopic ultrasound (EUS) should be performed for the precise localization of these tumors in the pancreas or duodenum. [8] Blood tests: ... The diagnosis of a somatostatinoma requires measuring fasting plasma somatostatin hormone concentration. A 3-phase CT, MRI, positron emission tomography (PET)-CT with gallium-labelled somatostatin analogs, or endoscopic ultrasound (EUS) should be performed for the precise localization of somatostatinomas in the pancreas or duodenum. [9] You have some tests to diagnose a somatostatinoma. This might include blood tests and an endoscopy. [10] The diagnosis of a somatostatinoma requires measuring fasting plasma somatostatin hormone concentration. A 3-phase CT, MRI, positron emission tomography (PET)-CT with gallium-labelled somatostatin analogs, or endoscopic ultrasound (EUS) should be performed for the precise localization of somatostatinomas in the pancreas or duodenum. [13] Diagnosis. If Somatostatinoma Syndrome Present: High Fasting Plasma Somatostatin (At Least Thee Times the Upper Limit of Normal) 18; Biopsy Not Required but Can Be Used for Grading 20; If Somatostatinoma Syndrome is Not Present (Most Common): Most Commonly Detected in the Workup of a Pancreatic or Duodenal Mass

Treatment Options for Pancreatic Somatostatinoma

Pancreatic somatostatinoma, a rare neuroendocrine tumor (NET), requires specialized treatment to manage its symptoms and slow down progression. The following are the most common drug treatments used:

• Chemotherapy: Combination treatment with intravenous 5-fluorouracil (5-FU) and streptozotocin is usually recommended for metastatic somatostatinoma [1].
• Somatostatin analogues: These medications can help manage excess somatostatin production, but their effectiveness may vary depending on the individual case [7].
• Streptozocin, 5-FU, and doxorubicin: These agents are commonly used in the treatment of somatostatin-secreting pancreatic neoplasms [9].

Additional Treatment Options

Other treatments that may be considered include:

• Surgery: Surgical removal of tumors is often recommended for localized disease [6].
• Hormone therapy: This type of treatment can help manage symptoms related to excess hormone production.
• Liver-directed therapy: For patients with metastatic disease, liver-directed therapies such as hepatic arterial occlusion or chemoembolization may be used.

Long-acting Somatostatin Analogues

A long-acting form of the somatostatin analogue (Sandostatin LAR Depot) is available, which can be administered once a month by injection into a muscle [3].

References:

[1] Apr 17, 2024 — Chemotherapeutic treatment of metastatic somatostatinoma usually consists of combination treatment with intravenous 5-fluorouracil (5-FU) and streptozotocin.

[2] by A Elangovan · 2023 · Cited by 7 — Somatostatinoma is a rare neuroendocrine tumor (NET) with an incidence of 1 in 40 million individuals and accounts for less than 5% of pancreatic NETs (pNETs).

[3] Aug 22, 2024 — There is also a long-acting form of the drug (called Sandostatin LAR Depot) that only needs to be given once a month, by injection into a muscle ...

[6] Jun 30, 2022 — The most common treatment is the surgical removal of the tumors.

[7] Apr 12, 2023 — The management of somatostatinomas includes medical treatment of the excess somatostatin production, surgical and/or radiological interventions ...

[9] Apr 17, 2024 — Streptozocin, 5-FU, and doxorubicin are the agents most commonly used in the treatment of somatostatin-secreting pancreatic neoplasms.