Interferon and meta-iodobenzylguanidin combinations in the treatment of metastatic carcinoid tumours.

Interferon (IFN) and meta-iodobenzylguanidin (MIBG) are active in metastatic carcinoids. In a phase II study, we evaluated the effect upon diagnostic 131I-MIBG uptake and the clinical response of the combination. 131I-MIBG scintigraphy was performed prior to treatment, after 8 weeks of IFN and after unlabelled MIBG. The tumour over non-tumour (T/NT) ratios were quantitatively determined by comparing counts in the centre of the tumour (liver metastases) with those in an adjacent area of normal liver uptake (T/NT1) and with abdominal background area (T/NT2). The T/NT1 ratio showed an increase of >10% in only four out of 21 patients (19%) after IFN (P = 0.178) and significantly more often in nine out of 18 patients (50%) after unlabelled MIBG (P = 0.016). The absolute uptake in tumour deposits was also increased if compared with the abdominal background (T/NT2: 23% increase after IFN and 83% increase after unlabelled MIBG). The combination produced 91% of patients with stable disease (using World Health Organisation criteria) at computed tomography scan and a biochemical response (a reduction of at least 50% in urinary 5-hydroxyindolacetic acid excretion) in 39%. IFN-alpha did not significantly improve tumour retention of 131I-MIBG. In contrast, unlabelled MIBG significantly improved biodistribution and tumour uptake in 83%. A synergistic effect was not seen.

Role of natriuretic peptides in the diagnosis and treatment of patients with carcinoid heart disease.

Carcinoid heart disease (CHD) occurs in 20-70% of the patients with metastatic well-differentiated neuroendocrine tumours (NET). We evaluated whether natriuretic peptides (ANP or NT-proBNP) are useful in early detection of CHD. Blood samples from 32 patients with NET were compared with cardiac ultrasound follow-up. CHD was defined as thickening of the tricuspid valve in the presence of grade III-IV/IV tricuspid valve regurgitation. CHD was found in nine out of 32 patients (28%), all with symptoms of the carcinoid syndrome compared to 65% in the 23 patients without CHD (P=0.04). Median levels of NT-proBNP and 5-HIAA were significantly higher in patients with CHD (894 ng l(-1) and 815 micromol 24 h(-1)) compared to those without (89 and 206 ng l(-1), P<0.001 and P=0.007). No significant differences were detected in ANP levels (P=0.11). Dilatation of the right atrium and ventricle as well as thickening of the tricuspid valve and degree of regurgitation were statistically significant correlated with NT-proBNP levels. The accuracy of NT-proBNP in the diagnosis of CHD was higher than that of ANP. A significantly better survival was observed in case of normal NT-proBNP values. In conclusion, NT-proBNP is helpful as a simple marker in the diagnosis of CHD. Survival is better in patients with normal levels of NT-proBNP.

Pathogenesis and treatment of pain caused by skin metastases in neuroendocrine tumours.

BACKGROUND: Prognosis of neuroendocrine tumours has improved during the last decade and one might expect that more patients with (sub)cutaneous metastases will be seen in the future. We investigated the cause of pain in skin metastases and tried to give recommendations about treatment options. METHODS: We compared histology of (sub)cutaneous metastases in four patients, two with severely painful skin lesions and two without pain. RESULTS: On the pathological slides there were no differences in neuroinvasion, angioinvasion or mitosis between painful and non-painful metastases. However, the painful metastases rapidly multiplied, while the others remained indolent in nature. Pain was very difficult to manage and did not respond to analgesics, irradiation or systemic treatment with interferon or chemotherapy. Local excision was the only successful treatment option. CONCLUSION: Histology did not show differences between painful and non-painful skin metastases. Local excision is the treatment of choice.

Evaluation of (111)In-pentetreotide, (131)I-MIBG and bone scintigraphy in the detection and clinical management of bone metastases in carcinoid disease.

Bone metastases are assumed to be rare in carcinoid disease and to be associated mainly with bronchial primaries. The aim of the present study was to evaluate the occurrence of bone metastases in patients with metastatic carcinoid tumours, and the role of various nuclear medicine modalities (bone scintigraphy, (111)In-pentetreotide and (131)I-MIBG) in its detection and clinical management. Nine (2 women, 7 men, median age 65 years) out of 86 consecutive carcinoid patients treated between 1987 and 1998 developed bone metastases (10%) with a median interval of 37 months between the diagnosis of metastatic carcinoid and bone metastases. Seven of them had non-bronchial primaries. (111)In-pentetreotide scintigraphy failed to detect the bone lesions in 50% of the cases, and (131)I-meta-iodobenzylguanidine(MIBG) scintigraphy in almost 80% of cases. Standard bone scintigraphy, however, was positive in all. Pain relief of bone metastases by means of radiation therapy was obtained in 5 of 6 patients. In another patient palliation of pain symptoms was obtained with Rhenium-186-hydroxyethylidene diphosphonate. Octreotide, Interferon of MIBG were ineffective for this purpose. It is concluded that bone metastases in carcinoid patients may be missed on (131)I-MIBG and (111)In-pentetreotide scintigraphy. Bone scintigraphy is a sensitive imaging technique. Diagnostic nuclear medicine modalities may be helpful in the clinical management of carcinoid disease.

Mucin-like carcinoma-associated antigen serum levels in patients with adenocarcinomas originating from ovary, breast and colon.

The mucin-like carcinoma-associated antigen (MCA) enzyme immunoassay was tested in 962 healthy controls. MCA levels were compared with CA 125 in 70 patients with benign and 76 with malignant ovarian tumors. In addition MCA was compared with CA 15.3 in 58 patients with breast cancer and with CEA in 50 patients with colon carcinoma. In healthy controls the 95th percentile cutoff of 19.2 U/ml appeared to be higher than generally used. With the common cutoff value of 14 U/ml, a 38% sensitivity and 100% specificity was reached in malignant versus benign ovarian tumors. In colorectal cancer only 4% of patients had elevated MCA serum levels (CEA: 50%). In breast cancer patients the MCA assay performed better than CA 15.3 although only 17.2% showed elevated levels (CA 15.3: 7.4%). Thus MCA seems to be of limited value in the diagnosis and follow-up of adenocarcinomas of breast, ovary or colon.