Malignancy in Slow Motion: Diagnosis of Biochemically Apparent, but Otherwise Occult Persistent Disease 21 Years After Resection of a Carcinoid Tumour of the Terminal Ileum.

Carcinoid tumors may relapse after a long time span following initial diagnosis, and relapse might be clinically inapparent despite biochemical indications due to a low sensitivity of conventional methods. We present the case of a patient who had biochemical indication for hidden disease persistence for more than two decades. In 1978, a 39-year-old man underwent surgery for a carcinoid tumour of the ileum measuring 3.5 cm with multiple local lymph-node metastases. After surgery, however, serotonin- and urinary 5-hydroxy-indole-acetic-acid (5-HIAA) remained markedly elevated, and persisted over more than 20 years at levels between 600 and 950 ng/ml for serum serotonin (normal range 40-400 ng/ml) and 29-35 mg/24 h for 5-HIAA (normal range 2-9 mg/24 h). Despite this, regular radiological follow-up, including sonography and CT-scan, did not reveal the location of suspected malignancy until 1999, when the patient was re-admitted to our hospital for a hypertensive episode. CT-scanning of the abdomen showed a singular lesion within the liver, which was verified as recurrence of the carcinoid by fine needle biopsy. Somatostatin receptor scintigraphy using [sup 111]In-DTPA-D-Phe[sup 1]-Octreotide revealed a second lesion within the liver along with local recurrence at the anastomosis, which was verified by surgery. While the propensity for late relapse of ileal carcinoids has repeatedly been demonstrated, a case with biochemical signs of disease persistence over a time span of 21 years before final diagnosis is unusual. In addition, our case reflects the low sensitivity of conventional radiological evaluation for localization of carcinoid tumours as compared to somatostatin receptor scanning. [ABSTRACT FROM AUTHOR]