Vipoma (Verner-Morrison's syndrome)

Description:

Vipoma represents not beta-cellular tumor of insular cells of a pancreas cosecreting the vasoactive intestinal peptide (VIP), leading to a syndrome of watery diarrhea, a hypopotassemia and an achlorhydria (WDHA syndrome). The diagnosis is established by determination of the VIP level of serum, localization of a tumor is determined by KT and endoscopic ultrasonography. Treatment of a vipoma consists in a surgical resection.

Vipoma reasons (Verner-Morrison's syndrome):

From these tumors of 50-75% are malignant and some of them can be rather big (7 cm). Approximately develops in 6% of a vipom as a part of a multiple endocrine neoplasia.

Vipoma - the APUD-system tumor producing excess amount of vasoactive intestinal polypeptide. In 90% of cases the tumor is localized in a pancreas, in 10% - has extra pancreatic localization (in the field of a sympathetic trunk). Approximately in half of cases the tumor is malignant.

In 1958 Mr. Verner and Morrison described a syndrome of water diarrhea at the patient with not beta-cellular tumor of a pancreas. Before this disease was option of a syndrome of Zollingera-Ellison, his atypical bezjyazvenny form with a hypopotassemia. Further researches showed that secretion not of gastrin is the reason of clinical manifestations in these cases, as at patients with an ulcerogenic syndrome, and the vasoactive intestinal peptide (VIP), from here and the name of a tumor - Vipoma. Sometimes this disease is called pancreatic cholera or on initial letters of the English words: water diarrhea, a hypopotassemia, an achlorhydria - a WDHA syndrome.

More than 70% the VIP malignant from % at the time of which diagnosis already have hepatic metastasises. At 20% of patients the symptom complex can be result of a hyperplasia of the insular device.

Supersecretion the VIP stimulates the expressed excretion with a small bowel and a pancreas of liquid and electrolytes which do not manage to be soaked up in a large intestine. Clinically it is expressed by profuse ponosa - not less than 700 ml/days, quite often exceeding 3-5 l that leads to dehydration. Loss of potassium, bicarbonates and magnesium promotes development of acidosis, the expressed weakness and tetanic spasms. Owing to dehydration and a gipokaliyemichesky nephropathy there is an azotemia. Approximately at a half of patients come to light hypo - and an achlorhydria. Among other manifestations of a syndrome it should be noted the hyperglycemia and a hypercalcemia which is not connected with the increased parathormone level.

Vipoma proceeds with the periods of remission and an aggravation. The VIP levels in the blood exceeding 80 pmol/L always have to guard concerning the tumoral nature of a disease.

Vipoma usually big therefore well come to light angiographically or by means of a computer tomography.

Vipoma symptoms (Verner-Morrison's syndrome):

The main symptoms of a vipoma include long plentiful watery diarrhea (on an empty stomach chair volume more than 750 - 1000 ml/day, and at the use of food is more than 3000 ml/day) and signs of a hypopotassemia, acidosis and dehydration. In half of cases diarrhea is constant; in the others weight of diarrhea changes for a long time. In 33% diarrhea lasted less than 1 year before establishment of the diagnosis, but in 25% cases it remained more than 5 years before establishment of the diagnosis. The lethargy, muscular weakness, nausea, vomiting and spastic abdominal pains are often observed. The hyperemia of the person like a carcinoid syndrome occurs at 20% of patients during diarrhea attacks.

1. Massive water diarrhea; the quantity lost during a day of water can make about 4-10 liters. At the same time along with water sodium and potassium are lost. Heavy dehydration, loss of body weight, a hypopotassemia develops. Diarrhea is caused by high secretion of sodium and water in an intestines gleam under the influence of vasoactive intestinal polypeptide.

2. Abdominal pains of uncertain, diffuse character.

3. Oppression of gastric secretion.

4. Rushes of blood and pristupoobrazny face reddening (owing to the expressed vasodilating effect of vasoactive intestinal polypeptide); the symptom is not constant, it is observed at 25-30% of patients.

5. The tendency to a lowering of arterial pressure, is possible the expressed arterial hypotension.

6. Increase in a gall bladder and education of stones in it (in connection with development of the expressed atony of a gall bladder under the influence of vasoactive intestinal polypeptide).

7. A convulsive syndrome (in connection with loss of a large amount of magnesium at diarrhea).

8. Disturbance of tolerance to glucose (the non-constant symptom, is caused by the strengthened disintegration of a glycogen and hypersecretion of a glucagon under the influence of vasoactive intestinal polypeptide).

Diagnosis:

Duration of diarrhea is not less than 3 (three) weeks.

2. The daily volume of a chair is not less than 700 ml or 700 g.

3. Starvation within 3 days does not reduce the daily volume of a chair less than 0,5 l (during starvation loss of water and electrolytes needs to be filled with intravenous administration of isotonic solution of table salt and electrolytes).

4. Hypo - or an achlorhydria of a gastric juice.

5. High content in blood of vasoactive intestinal polypeptide.

6. Detection of a tumor of a pancreas by means of a computer tomography or a magnetic resonance tomography (is more rare – sonografiya).

Treatment of a vipoma (Verner-Morrison's syndrome):

First of all transfusion of liquids and electrolytes is required. Completion of bicarbonate in connection with its loss with a chair is necessary for prevention of acidosis. As considerable losses of water and electrolytes with a stake are observed, the regidratation continuous intravenous infusions can become difficult.

Oktreotid usually manages diarrhea, but introduction of high doses of drug can be required. Respondents note positive effect from use of an oktreotid of the prolonged action on 20-30 mg intramusculary once a month. The patients accepting октреотид in addition have to accept pancreatic enzymes because октреотид suppresses secretion of pancreatic enzymes.

The resection of a tumor is effective at 50% of patients at the localized process. At innidiation of a tumor the resection of all visible tumor can provide temporary reduction of symptoms. The combination of a streptozotsin and doxorubicine can reduce diarrhea and volume of a tumor if objective improvement is observed (in 50-60%). The chemotherapy is inefficient.

Drug and preoperative treatment of a vipoma consists in massive transfusion of liquid and electrolytes, glucocorticoids are sometimes used. The chemotherapy at the malignant metastasizing Vipoma is carried out by means of a streptozototsin. The last in a varying degree causes remission of process in 50% of patients.

Surgical treatment of a vipoma is effective only during radical removal of all functioning tumoral fabric that works well not always. In the absence of a tumor at explicit clinical laboratory displays of a disease the distal pancreatectomy is recommended.