Patients with large or metastatic carcinoid tumors may develop the carcinoid syndrome during surgical manipulation of the tumor, resulting in serious perioperative complications. Kinney et al identified risk factors associated with complications following resection of intra-abdominal metastases in patients with malignant carcinoid tumors. The authors are from the Mayo Clinic.


Patients at higher risk for perioperative complications:

(1) presence of carcinoid heart disease

(2) very high urinary 5-HIAA excretion

(3) failure to receive intra-operative octreotide (a somatostatin analogue)



• Intra-operative octreotide decreased intra-operative complications but not post-operative ones.

• The normal urinary 5-HIAA excretion was <= 6 mg/day (31.4 µmol per 24 hours).

• The conversion of urinary 5-HIAA excretion from mg per day to µmol/d is to multiply by 5.23.

• The level of urinary 5-HIAA separating risk groups was not given. Patients without complications had a mean excretion of 78 mg per 24 hours while those with complications had a mean excretion of 200 mg per 24 hours.

• For the implementation I decided (a) to express urinary 5-HIAA as multiples of the upper limit of normal range and (b) to use > 20 times as the higher risk group.


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