Possible Carcinoid Tumor


Question

I have recently seen an Indian man, aged 48 years,smoker and social drinker, suffering with hypertension for a long time. Over the last few months, he develops flushing on and off, aggravated during times of anxiety, specially when work pressure escalates.Physical examination reveals, BMI 25, BP 180/100 (both arms), all pulses palpable, systoliv flow murmur at apex. Labs show--- raised urea and high creatinine ( 2.6 mmol/l), fasting glucose 115 mg/dl, and 2 hrs post prandial glucose 166 mg/dl. 24 hrs urinary adrenaline and nor adrenaline and total catecholamine levels normal. 5 HIAA markedly raised. He complained of symptoms of gastritis ---an upper GI endoscopy showed mild antral gastritis. My working diagnosis is Carcinoid tumour

My questions are?

Is the hypertension related to Carcinoid , or is this a separate problem?

  1. I n view of his significant degree of renal impairment, can he undergo localising scans like MIBG, which is available at our centre.
  2. What other hormones should I test?

I shall be very much obliged if you kindly enlighten me about this computer software engineer please Thanking you in anticipation.Dr Sagarika Mukherjee MRCP(UK), MRCP(Ireland), CCST(UK), AMRI Hospital, Calcutta, India

Response

1. It is not clear than this is carcinoid-you say the 5HIAA is very high but of course one would like to see the numbers and be sure there has been adequate preparation such as avoiding serotonin containing foods before doing the urine collection. It would also be wise to get blood serotonin values at the same time.

2. Your patient seem to be evolving diabetes and has IGT by your numbers, These people may have autonomic dysfunction and then get gustatory sweating associated with flushing of the upper half of the body while the lower half remains dry. An autonomic function test would help. Simply the measurement of heart rate variability

3. The gastritis may then be due to altered gastric emptying, but alternatively could be due to atrophic gastritis with the possibility of pernicious anemia. You need a gastrin and gastric pH to determine if this is so. These people then get secondary carcinoid s of the gastric mucosa.

4. up to 50% of patients with carcinoid have hypertension in the absence of Pheochromocytoma. You need to obtain fractionated urine or plasma metanephrines to make this diagnosis and the best measure today for a pheo is the plasma chromogranin A level. The chromgranin molecule is processed to pancreastatin and Vasostatin and the latter is a potent vasoconstrictor so you may not nee to postulate a pheo but simply a carcinoid

5. MIBG scans are usually only helpful if the metanephrine levels are markedly elevated and you need the high affinity tracer 123I MIBG to obtain useful pictures.

Hope this helps, AIV Aaron Vinik, MD