Vitamin D and vitamin B12 deficiencies are common in patients with midgut carcinoid (SI-NET).

BACKGROUND/OBJECTIVES: Patients with small intestinal neuroendocrine tumours (SI-NET) often have diarrhoea from hormonal overproduction, surgery and medical treatment, leading to malabsorption of bile salts, fats, vitamin B12 and fat-souble vitamins. This could lead to malnutrition. SUBJECTS/METHODS: We assessed nutritional status in 50 consecutive out patients with disseminated SI-NET, 25 patients in each cohort. The first cohort was descriptive and the second cohort supplemented with vitamin D, B12 and calcium. Vitamin D deficiency was defined as <50 nmol/l. All patients were assessed by clinical chemistry and dual-energy X-ray absorptiometry (DXA) and interviewed about weight changes, appetite, gastrointestinal disorders, sunhabits and the use of supplements. RESULTS: In the first cohort, 29% of the patients were severely and 17% moderately vitamin D deficient. In patients without prior substitution, 32% had subnormal vitamin B12 levels. Seventy-six percent had low bone density. In the second cohort with vitamin and mineral supplementation, none had severe vitamin D deficiency, but 28% had moderate deficiency. No patient had subnormal vitamin B12 levels. Sixty percent had low bone density. The serum levels of vitamin D and B12 were higher and parathyroid hormone (PTH) lower in the second cohort compared with the first cohort (P⩽0,022). Vitamin D and PTH were negatively correlated, r=-30, P=⩽0.036. CONCLUSIONS: Low serum levels of vitamin D and vitamin B12, and low bone density are common in patients with disseminated SI-NET. Supplementation of vitamin D, B12 and calcium resulted in higher serum levels of vitamins, lower PTH levels and diminished severe vitamin D deficiency and is thus recommended as standard care.

A novel statistical analysis method to improve the detection of hepatic foci of (111)In-octreotide in SPECT/CT imaging.

BACKGROUND: Low uptake ratios, high noise, poor resolution, and low contrast all combine to make the detection of neuroendocrine liver tumours by (111)In-octreotide single photon emission tomography (SPECT) imaging a challenge. The aim of this study was to develop a segmentation analysis method that could improve the accuracy of hepatic neuroendocrine tumour detection. METHODS: Our novel segmentation was benchmarked by a retrospective analysis of patients categorized as either (111)In-octreotide positive ((111)In-octreotide(+)) or (111)In-octreotide negative ((111)In-octreotide(-)) for liver tumours. Following a 3-year follow-up period, involving multiple imaging modalities, we further segregated (111)In-octreotide-negative patients into two groups: one with no confirmed liver tumours ((111)In-octreotide(-)/radtech(-)) and the other, now diagnosed with liver tumours ((111)In-octreotide(-)/radtech(+)). We retrospectively applied our segmentation analysis to see if it could have detected these previously missed tumours using (111)In-octreotide. Our methodology subdivided the liver and determined normalized numbers of uptake foci (nNUF), at various threshold values, using a connected-component labelling algorithm. Plots of nNUF against the threshold index (ThI) were generated. ThI was defined as follows: ThI = (c max - c thr)/c max, where c max is the maximal threshold value for obtaining at least one, two voxel sized, uptake focus; c thr is the voxel threshold value. The maximal divergence between the nNUF values for (111)In-octreotide(-)/radtech(-), and (111)In-octreotide(+) livers, was used as the optimal nNUF value for tumour detection. We also corrected for any influence of the mean activity concentration on ThI. The nNUF versus ThI method (nNUFTI) was then used to reanalyze the (111)In-octreotide(-)/radtech(-) and (111)In-octreotide(-)/radtech(+) groups. RESULTS: Of a total of 53 (111)In-octreotide(-) patients, 40 were categorized as (111)In-octreotide(-)/radtech(-) and 13 as (111)In-octreotide(-)/radtech(+) group. Optimal separation of the nNUF values for (111)In-octreotide(-)/radtech(-) and (111)In-octreotide(+) groups was defined at the nNUF value of 0.25, to the right of the bell shaped nNUFTI curve. ThIs at this nNUF value were dependent on the mean activity concentration and therefore normalized to generate nThI; a significant difference in nThI values was found between the (111)In-octreotide(-)/radtech(-) and the (111)In-octreotide(-)/radtech(+) groups (P < 0.01). As a result, four of the 13 (111)In-octreotide(-)/radtech(+) livers were redesigned as (111)In-octreotide(+). CONCLUSIONS: The nNUFTI method has the potential to improve the diagnosis of liver tumours using (111)In-octreotide.

Systematic review of surgery and outcomes in patients with primary aldosteronism.

BACKGROUND: Primary aldosteronism (PA) is the most common cause of secondary hypertension. The main aims of this paper were to review outcome after surgical versus medical treatment of PA and partial versus total adrenalectomy in patients with PA. METHODS: Relevant medical literature from PubMed, the Cochrane Library and Embase OvidSP from 1985 to June 2014 was reviewed. RESULTS: Of 2036 records, 43 articles were included in the final analysis. Twenty-one addressed surgical versus medical treatment of PA, four considered partial versus total adrenalectomy for unilateral PA, and 18 series reported on surgical outcomes. Owing to the heterogeneity of protocols and reported outcomes, only a qualitative analysis was performed. In six studies, surgical and medical treatment had comparable outcomes concerning blood pressure, whereas six showed better outcome after surgery. No differences were seen in cardiovascular complications, but surgery was associated with the use of fewer antihypertensive medications after surgery, improved quality of life, and (possibly) lower all-cause mortality compared with medical treatment. Randomized studies indicate a role for partial adrenalectomy in PA, but the high rate of multiple adenomas or adenoma combined with hyperplasia in localized disease is disconcerting. Surgery for unilateral dominant PA normalized BP in a mean of 42 (range 20-72) per cent and the biochemical profile in 96-100 per cent of patients. The mean complication rate in 1056 patients was 4·7 per cent. CONCLUSION: Recommendations for treatment of PA are hampered by the lack of randomized trials, but support surgical resection of unilateral disease. Partial adrenalectomy may be an option in selected patients.

Specific binding and uptake of 131I-MIBG and 111In-octreotide in metastatic paraganglioma--tools for choice of radionuclide therapy.

Tumor-specific uptake of the radiolabeled nor-epinephrine analogue meta-iodobenzylguanidine via norepinephrine transporter or radiolabeled somatostatin analogues octreotide/octreotate via somatostatin receptors offers possibilities to diagnose and treat metastatic pheochromocytoma/paraganglioma. High uptake of 123I-meta-iodobenzylguanidine is dependent on high expression of vesicular monoamine transporters responsible for mediating uptake of biogenic amines into dense core granules. A patient with metastatic paraganglioma (liver and bone metastases) underwent surgical removal of the primary after injection of 131I-meta-iodobenzylguanidine and 111In-octreotide. Radioactivity was determined in biopsies from tumor and normal tissue biopsies. The tumor/blood concentration value was high: 180 for 131I-meta-iodobenzylguanidine 3 h after injection and 590 for 111In-octreotide 27 h after injection. Studies of primary tumor cell cultures demonstrated increased cell membrane binding and internalization over time for 131I-meta-iodobenzylguanidine. The vesicular monoamine transporter antagonist reserpine and the norepinephrine transporter inhibitor clomipramine reduced internalization by 90% and 70%, respectively, after 46 h of incubation. The results demonstrated increased cell membrane binding and internalization over time also for 111In-octreotide. Internalization was highest for a low concentration of 111In-octreotide. Excess of octreotide reduced internalization of 111In-octreotide with 75% after 46 h of incubation. In conclusion, uptake and tumor/blood concentration values of radiolabeled meta-iodobenzylguanidine and somatostatin analogues can be determined for metastatic pheochromocytoma/paraganglioma to evaluate the possibility to use one or both agents for therapy. For this patient, the high tumor/blood values clearly demonstrated that therapy using both radiopharmaceuticals would be most beneficial. In vitro studies verified specific cell-membrane binding and internalization in tumor cells of both radiopharmaceuticals.

Cohort study of patients with adrenal lesions discovered incidentally.

BACKGROUND: This prospective cohort study investigated the incidence, clinical features and natural history of incidentally discovered adrenal mass lesions (adrenal incidentaloma, AI) in an unselected population undergoing radiological examination. METHODS: During an 18-month period, all patients with AI were reported prospectively from all 19 radiology departments in western Sweden. Inclusion criteria were: incidentally discovered adrenal enlargement or mass lesion in patients without extra-adrenal malignancy on detection. Clinical and biochemical evaluation was performed on inclusion and after 24 months. Computed tomography (CT) of the adrenals was scheduled at 4, 12 and 24 months. Magnetic resonance imaging was performed for lesions larger than 20 mm. The indications for surgical excision were: hormone activity, lesion diameter more than 30 mm, lesion growth or other radiological features suspicious of malignancy. RESULTS: Of 534 patients assessed for eligibility, 226 (mean age 67 years, 62·4 per cent women; mean lesion diameter 23·9 mm, 22·6 per cent bilateral) fulfilled the inclusion criteria. Mean follow-up was 19·0 months. After baseline evaluation, 14 patients had surgery owing to primary hyperaldosteronism (3), catecholamine-producing tumour (1), tumour size (6), size and indication of subclinical hypercortisolism (3) and metastasis (1). No hypersecreting lesions were confirmed during follow-up; one patient underwent adrenalectomy for a suspected phaeochromocytoma (adrenocortical adenoma at histopathology). No primary adrenal malignancy was found. CONCLUSION: In this prospective cohort study 6·6 per cent of patients with an AI had surgery and benign hormone-producing tumours were verified in 3·1 per cent. Repeat CT and hormone evaluation after 2 years did not increase the sensitivity for diagnosis of malignant or hormone-producing tumours.

Prognostic factors for survival after surgery for adrenal metastasis.

AIM: To better define the indications for adrenalectomy for adrenal metastasis we have analysed factors predicting survival in our institutional series. METHODS: A consecutive series of 30 patients undergoing adrenalectomy for metastasis (1996-2007), excluding patients with simultaneous ipsilateral renal cell carcinoma (RCC), was studied. Metastases were regarded as synchronous (<6 mo), or metachronous (>6 mo), depending on the interval after primary surgery. Survival was calculated from time of adrenalectomy and factors influencing survival were identified. RESULTS: The tumour diagnoses were RCC n = 9, malignant melanoma n = 5, non-small-cell lung cancer n = 5, colorectal carcinoma n = 4, foregut carcinoid n = 2, adrenocortical carcinoma, breast cancer, hepatocellular carcinoma, urothelial carcinoma, and liposarcoma (one each); nine adrenal metastases were synchronous and 21 metachronous. Ten patients had undergone previous surgery for extra-adrenal metastases. Out of 30 adrenalectomies 10 were laparoscopic (LAdx) and 20 open (OAdx) procedures without surgical complications. The local recurrence rate was low: LAdx 1/10, OAdx 1/20, and the median survival was 23 months. Independent prognosticators of favourable survival were adrenalectomy for potential cure (p = 0.01), no previous metastasis surgery (p = 0.02), and tumour type (p = 0.043), with better prognosis for patients with adrenal metastasis from colorectal carcinoma and RCC and worse prognosis in non-small-cell lung cancer and malignant melanoma. CONCLUSIONS: Surgery for adrenal metastasis is safe and the indication for this procedure in an individual patient can be supported by several prognostic factors. The survival benefit in patients with adrenalectomy for potential cure indicates a therapeutic value of adrenalectomy in selected patients.

The long-term survival in adrenocortical carcinoma with active surgical management and use of monitored mitotane.

Adrenocortical carcinoma (ACC) is a rare tumour disease with sinister prognosis also after attempts to radical surgery; better prognosis is seen for low-stage tumours. Adjuvant treatment with the adrenolytic drug mitotane has been attempted, but not proven to prevent from recurrence. The drug may offer survival advantage in case of recurrence. The aim of this single-centre study (1979-2007) of 43 consecutive patients was to evaluate the long-term survival after active surgical treatment combined with monitored mitotane (to reduce side effects of the drug). The series is unique, since all patients were offered a period of mitotane as adjuvant or palliative treatment; six patients refused mitotane. Despite a high proportion of high-stage tumours (67%), the complete resection rate was high (77%). The disease-specific 5-year survival was high (64.1%); very high for patients with low-stage tumours without evident relation to mitotane levels. Patients with high-stage tumours had a clear survival advantage with mitotane levels above a threshold of 14 mg/l in serum. The hazard ratio for patients with high mitotane levels versus all patients indicates a significant effect of the drug. The results indicate that adjuvant mitotane may be the standard of care for patients with high-stage ACC after complete resection.

Prolonged survival after hepatic artery embolization in patients with midgut carcinoid syndrome.

BACKGROUND: Hepatic artery embolization (HAE) is a palliative treatment for patients with liver metastases from neuroendocrine tumours. HAE reduces hormonal symptoms, but its impact on survival has been questioned. METHODS: Biochemical responses and survival in consecutive patients with disseminated liver metastases from midgut carcinoid tumours were studied after HAE. Repeat HAE was performed in selected patients with radiological and biochemical signs of progression. RESULTS: Of 107 patients who had HAE, the median survival from the first procedure was 56 (range 1-204) months. Prolonged survival showed a strong correlation with reduction of urinary 5-hydroxyindoleacetic acid (P = 0.003) and plasma chromogranin A (P = 0.001) levels. The biochemical response to repeat HAE was similar to that for the first procedure (P = 0.002). The complication rate was low (7.5 per cent), as was the mortality rate (1.9 per cent) within 1 month of HAE. CONCLUSION: HAE is safe, provides good control of hormonal symptoms, and prolongs survival in biochemically responsive patients. It is a valuable palliative option for patients with midgut carcinoid syndrome due to liver metastases and can be repeated in patients with a favourable response to the first procedure.

Long-term outcome of a large series of patients surgically treated for pheochromocytoma.

OBJECTIVE: To analyse the morbidity, mortality and long-term outcome in a consecutive series of surgically treated patients with pheochromocytoma (PC), or paraganglioma (PG), from the western region of Sweden between 1950 and 1997. PATIENTS: All patients (n = 121) who had been hospitalized and treated for PC/PG over 47 years. DESIGN: Retrospective review of patients with PC/PG regarding presenting symptoms, tumour characteristics, clinical management and long-term outcome after treatment. SETTING: One referral centre for all patients from the western region of Sweden. RESULTS: During an observation of 15 +/- 6 years, 42 patients died vs. 23.6 expected in the general population (P < 0.001). There was no intra- or post-operative mortality. Four patients with sporadic disease died of malignant PC and six with hereditary disease of associated neuroectodermal tumours. Five patients died of other malignancies, 20 of cardiovascular disease and seven of other causes. Besides older age at primary surgery, elevated urinary excretion of methoxy-catecholamines was the only observed risk factor for death (P = 0.02). At diagnosis 85% of the patients were hypertensive; one year after surgery more than half were still hypertensive. However, pre- and post-operative hypertension did not influence the risk for death versus controls. CONCLUSION: Pheochromocytoma/PG can be safely treated by surgery. Death of malignant PC/PG was unusual, but the patients as a group had an increased risk of death. We recommend life-long follow-up of patients treated for PC/PG with screening for recurrent tumour in sporadic cases and for associated tumours in hereditary cases. This strategy would also be helpful in diagnosing cardiovascular disease at an early stage.

Antisecretory factor counteracts secretory diarrhoea of endocrine origin.

BACKGROUND: Dietary induction of antisecretory factor (AF) can reduce diarrhoea in patients with inflammatory bowel disease. Patients with neuroendocrine tumours may suffer from diarrhoea with a prominent secretory component. We studied if AF-therapy could affect this type of diarrhoea. METHODS: Six patients with the midgut carcinoid syndrome and two with metastasizing medullary thyroid carcinoma (MTC) participated. Effects of intake of AF, in the form of AF-rich egg powder (AF-egg), and induction of endogenous AF-activity by intake of specially processed cereals (SPCs) were studied. In an initial open part of the study all patients received AF-egg for 4 weeks, followed by a double-blind crossover period with SPC and control cereals (CCs) for 6 weeks each. Daily number of bowel movements at the end of each treatment period was registered. RESULTS: Treatment with AF-egg resulted in a decrease of bowel movements in seven patients (P<0.01). Registrations of bowel movements from both SPC and CC diet periods were obtained from five patients. The daily number of bowel movements was lower during the SPC-period compared to the period with CC (P<0.05). All patients had low levels of AF-activity in serum at baseline. During treatment with AF-egg, the mean level increased slightly. AF-activity was higher (P<0.05) after SPC compared to the CC diet. CONCLUSIONS: In a group of patients with endocrine diarrhoea, AF-activity could be induced, and AF-therapy reduced the number of bowel movements.

Uptake of meta-iodobenzylguanidine in neuroendocrine tumours is mediated by vesicular monoamine transporters.

The radio-iodinated noradrenaline analogue meta-iodobenzylguanidine (MIBG) can be used for scintigraphy and radiation therapy of neuroendocrine (NE). The aim of the present study was to study the importance of vesicular monoamine transporters (VMATs) for the uptake of (123)I-MIBG in NE tumours. In nude mice, bearing the human transplantable midgut carcinoid GOT1, all organs and xenografted tumours accumulated (123)I after i.v. injection of (123)I-MIBG. A high concentration of (123)I was maintained in GOT1 tumours and adrenals, which expressed VMATs, but rapidly decreased in all other tissues. In the VMAT-expressing NE tumour cell lines GOT1 and BON and in VMAT-expressing primary NE tumour cell cultures (carcinoids, n=4 and pheochromocytomas, n=4), reserpine significantly reduced the uptake of (123)I-MIBG. The membrane pump inhibitor clomipramine had no effect on the uptake of (123)I-MIBG in GOT1 and BON cells, but inhibited the uptake in one out of four primary carcinoid cell cultures and three out of four primary pheochromocytoma cell cultures. In conclusion, VMATs and secretory granules are of importance for the uptake and retention of (123)I-MIBG in NE tumours. Information about the type and degree of expression of VMATs in NE tumours may be helpful in future to select patients suitable for radiation therapy with radio-iodinated MIBG.

Neoadjuvant, adjuvant and palliative treatment of gastrointestinal stromal tumours (GIST) with imatinib: a centre-based study of 17 patients.

Malignant gastrointestinal stromal tumours (GIST) have a poor prognosis. Since these tumours are resistant to conventional radiation and chemotherapy, surgery has been the mainstay of treatment. However, surgery is usually inadequate for the treatment of malignant GIST. Imatinib, a KIT tyrosine kinase inhibitor, has recently been found to have a dramatic antitumour effect on GIST. In this centre-based study of 17 consecutive patients with high-risk or overtly malignant GIST, imatinib was used in three different settings - palliatively, adjuvantly, and neoadjuvantly. The treatment was found to be safe and particularly effective in tumours with activating mutations of exon 11 of the KIT gene. Clinical response to imatinib treatment correlated morphologically to tumour necrosis, hyalinisation, and reduced proliferative activity. The value of neoadjuvant imatinib treatment was illustrated in one case.

111In-labelled octreotide binding by the somatostatin receptor subtype 2 in neuroendocrine tumours.

BACKGROUND: The aim of this study was to investigate the importance of somatostatin receptor subtype 2 (SSTR2) expression for 111In-labelled diethylenetriamine-pentaacetic acid (DTPA)-D-Phe1-octreotide binding and uptake of 111In in neuroendocrine tumours. METHODS: 111In activity concentrations in surgical biopsies from neuroendocrine tumours (midgut carcinoid and medullary thyroid carcinoma), breast carcinoma and blood were determined 1-8 days after intravenous injection of 111In-labelled DTPA-D-Phe1-octreotide (140-350 MBq). The ratio of 111In activity concentrations between tumour tissue and blood (T/B value) was calculated. The expression of SSTR2 messenger RNA (mRNA) in tumour biopsies was quantitated by ribonuclease protection assay and SSTR2 protein was localized by immunocytochemistry. RESULTS: T/B values were highest for tumour biopsies from midgut carcinoids (mean 160 (range 4-1200); n = 65) followed by medullary thyroid carcinoma (mean 38 (range 2-350); n = 88) and breast carcinoma (mean 18 (range 4-41); n = 4). The expression of SSTR2 mRNA (relative to the NCI-H69 cell line) was highest in tumour biopsies from midgut carcinoids (mean 2.5 (range 0.83-6.0); n = 40) followed by medullary thyroid carcinoma (mean 1.3 (range 0.20-6.0); n = 7) and breast carcinoma (mean 0.66 (range 0.29-1.0); n = 9). In tumour biopsies SSTR2 protein was localized exclusively to tumour cells. CONCLUSION: Midgut carcinoid tumours showed a much higher level of SSTR2 expression than medullary thyroid carcinoma in accordance with superior tumour imaging by octreotide scintigraphy. The high SSTR2 mRNA values and T/B values observed in midgut carcinoid tumours were positively correlated.

Differential expression of vesicular monoamine transporter (VMAT) 1 and 2 in gastrointestinal endocrine tumours.

Neuroendocrine tumours are characterized by their capacity to produce hormones, which are stored in vesicles and secretory granules. Demonstration of granule/vesicle proteins in tumours is taken as evidence of neuroendocrine differentiation. Vesicular monoamine transporters (VMAT1 and VMAT2) mediate the transport of amines into vesicles of neurons and endocrine cells. The expression of VMAT1 and VMAT2 and the usefulness of VMAT1 and VMAT2 in the histopathological diagnosis of gastrointestinal endocrine tumours have not been fully explored. This study therefore investigated the expression of VMAT1 and VMAT2 in 211 human gastrointestinal tumours by immunocytochemistry and western blotting. VMAT1 and/or VMAT2 were demonstrated in the majority of amine-producing endocrine tumours of gastric, ileal, and appendiceal origin. Serotonin-producing endocrine tumours (ileal and appendiceal carcinoids) expressed predominantly VMAT1, while histamine-producing endocrine tumours (gastric carcinoids) expressed VMAT2 almost exclusively. In peptide-producing endocrine tumours such as rectal carcinoids and endocrine pancreatic tumours, only a small number of immunopositive tumour cells were observed. No labelling was found in non-endocrine tumours, including gastric, colorectal and pancreatic adenocarcinomas and gastrointestinal stromal tumours. In conclusion, VMAT1 and VMAT2 are differentially expressed by gastrointestinal endocrine tumours, with a pattern specific for each tumour type, reflecting their neuroendocrine differentiation and origin. VMAT1 and VMAT2 may therefore become valuable markers in the classification of neuroendocrine tumours and may also indicate patients suitable for radioisotope treatment operating via these transporter systems.

Intraoperative tumour detection using 111In-DTPA-D-Phe1-octreotide and a scintillation detector.

Intraoperative tumour detection has been used in many applications. The examined tumour forms have varied and different detector systems and radiopharmaceuticals have also been used. The aim of this study was to evaluate and compare the ability of an NaI(T1) scintillation detector to detect primary tumours and metastases in patients with different endocrine tumour types (e.g. carcinoid tumours, endocrine pancreatic tumours and thyroid tumours) and in patients with breast carcinoma or benign thyroid lesions, on the basis of their somatostatin receptor expression after i.v. injection of 111In-DTPA-D-Phe1-octreotide. Thirty patients were injected with 111In-DTPA-D-Phe1-octreotide intravenously. Scintigraphic images were taken 1 day after injection of the radiopharmaceutical, and surgery was performed 1-7 days post injection. An NaI(T1) scintillation detector was used for intraoperative tumour detection. Tissue samples were collected during surgery for determination of 111In activity concentration and histopathological examination. The scintigraphic images were positive in 29 out of 30 patients. Intraoperative tumour detection was successful in 43 of 66 collected biopsies: 10 out of 11 for carcinoid tumours, 7 out of 10 for medullary thyroid carcinoma (MTC) and 14 out of 22 for breast cancer. On the basis of our findings we conclude that intraoperative tumour detection with 111In-DTPA-D-Phe1-octreotide using this NaI(T1) detector can be successful especially for carcinoid tumours and endocrine pancreatic tumours, due to the relatively high activity concentrations in these tumour types, but is less successful in other forms of thyroid cancer, including MTC, and breast cancer. For successful intraoperative detection, the detector characteristics are also very important, and further improvement of the detector systems is required to increase the sensitivity and specificity.

Cytotoxic treatment of adrenocortical carcinoma.

Adrenocortical carcinoma (ACC) is a rare, aggressive tumor that is often detected in an advanced stage. Medical treatment with the adrenotoxic drug mitotane has been used for decades, but critical prospective trials on its role in residual disease or as an adjuvant agent after surgical resection are still lacking. The concept of a critical threshold plasma level of the drug must be confirmed in controlled studies. Because individual responsiveness cannot be predicted, the use mitotane is still advised for nonresectable disease. In case of cortisol or other steroid overproduction, several drugs (e.g., ketoconazole or aminoglutethimide) may be used. Chemotherapy with single agents (e.g., doxorubicin or cisplatin) have been disappointing, with low response rates (< 30%) and a short response duration. Part of this refractoriness may be explained by the fact that ACC tumors express the multidrug-resistance gene MDR-1. Chemotherapy with multiple agents has been tested in smaller series and has resulted in significant side effects. The best results were achieved by the combination of etoposide, doxorubicin, and cisplatin associated with mitotane, achieving a response rate of 54%, including individual complete responses. To be able to make progress in treating advanced ACC disease, adjuvant multicenter trials must be encouraged. When mitotane-based therapies are used, monitored drug levels are mandatory.

Prediction of prognosis by echocardiography in patients with midgut carcinoid syndrome.

BACKGROUND: The association between malignant midgut carcinoid tumours and right-sided cardiac lesions is well known, but the pathogenetic link between tumour secretion and valvular disease is still obscure. The purpose of this investigation was to describe the morphological and functional changes of valvular heart disease in a large patient series and to correlate these findings with hormonal secretion and prognosis. METHODS: Of 64 consecutive patients with the midgut carcinoid syndrome followed between 1985 and 1998, valvular heart disease was evaluated in 52 patients by two-dimensional echocardiography, Doppler estimation of valvular regurgitation and flow profiles. A majority was also evaluated with exercise electrocardiography and spirometry. RESULTS: Structural and functional abnormalities of the tricuspid valve were found in 65 per cent of patients, while only 19 per cent had pulmonary valve regurgitation. Long-term survival was related to excessive urinary excretion of 5-hydroxyindole acetic acid of over 500 micromol in 24 h, but the main predictor of prognosis was the presence of severe structural and functional abnormalities of the tricuspid valve. Although advanced tricuspid abnormalities were prevalent in this series, only one patient died from right ventricular heart failure. CONCLUSION: Tricuspid valvular disease is a common manifestation of the midgut carcinoid syndrome and advanced changes are associated with poor long-term survival. Active surgical and medical therapy of the tumour disease reduced the hormonal secretion and, combined with cardiological surveillance, made right ventricular heart failure a rare cause of death in these patients.

A transplantable human carcinoid as model for somatostatin receptor-mediated and amine transporter-mediated radionuclide uptake.

A human midgut carcinoid tumor was successfully transplanted into nude mice and propagated for five consecutive generations (30 months) with well-preserved phenotype. Tumor cells in nude mice expressed identical neuroendocrine markers as the original tumor, including somatostatin receptors (somatostatin receptors 1 to 5) and vesicular monoamine transporters (VMAT1 and VMAT2). Because of the expression of somatostatin receptors and VMAT1 and VMAT2 the grafted tumors could be visualized scintigraphically using the somatostatin analogue 111In-octreotide and the catecholamine analogue 123I-metaiodobenzylguanidine. The biokinetics of the somatostatin analogue 111In-octreotide in the tumors was studied and showed a high retention 7 days after administration. Cell cultures were re-established from transplanted tumors. Immunocytochemical and ultrastructural studies confirmed the neuroendocrine differentiation. The human origin of transplanted tumor cells was confirmed by cytogenetic and fluorescence it situ hybridization analyses. Spontaneous secretion of serotonin and its metabolite, 5-hydroxyindole acetic acid, from tumor cells was demonstrated. The tumor cells increased their [Ca2+]i in response to beta-adrenoceptor stimulation (isoproterenol) and K+-depolarization. All somatostatin receptor subtypes could be demonstrated in cultured cells. This human transplantable carcinoid tumor, designated GOT1, grafted to nude mice, will give unique possibilities for studies of somatostatin receptor- and VMAT-mediated radionuclide uptake as well as for studies of secretory mechanisms.

Interventional treatment of gastrointestinal neuroendocrine tumours.

Neuroendocrine (NE) tumours of the gastrointestinal tract (carcinoids and endocrine pancreatic tumours) are rare diseases. In the presence of liver metastases these patients may suffer from disabling symptoms due to hormone overproduction. Patients with localized disease can be resected for cure and also patients with liver metastases can undergo potentially curative tumour resection. However, long-term follow-up of the latter cases indicates frequent recurrence of tumour. Using close biochemical monitoring of tumour markers combined with newer techniques for tumour visualization, these recurrences can often be diagnosed at an early stage so that repeat surgical procedures can be performed. During the last years very active surgery has been recommended for NE tumours, many of which have a relatively slow growth. Even in patients not amenable to curative liver surgery, debulking can be considered if the main tumour burden can be safely excised. The primary aim of this type of treatment is palliation of hormonal symptoms. An important question is whether the aggressive treatment actually prolongs survival. No prospective studies have been performed. Such studies are hampered by the lack of strict surgical programs running over long periods and the relative rarity of NE tumours. Liver transplantation may be another treatment modality in selected cases.

111In-DTPA-D-Phe1-octreotide binding and somatostatin receptor subtypes in thyroid tumors.

UNLABELLED: The purpose of this study was to evaluate the potential for therapy of thyroid tumors using the radiolabeled somatostatin (SS) analog octreotide. METHODS: Concentrations of 111In activity in human thyroid tumors and normal thyroid tissue and blood samples were determined 1-15 d after intravenous injection of 111In-diethylenetriaminepentaacetic acid-Phe1-octreotide. The results were compared with SS receptor (sstr subtype profile (by Northern blot analysis) and the relative expression of the second subtype, sstr2 (by ribonuclease protection assay, RPA). The true tumor volumes in lymph node metastases from 1 patient were estimated. In total, tissues from 68 patients were included in the study. RESULTS: The highest tumor-to-blood ratio (T/B) for medullary thyroid carcinoma (MTC) was 360; for follicular adenoma (FA), 190; for Hurthle cell adenoma (HCA), 140; and for Hurthle cell carcinoma (HCC) and papillary carcinoma (PC), 70. The corresponding value was 7-18 for normal thyroid tissue, with higher values for colloid goiter (8-48) and thyroiditis (7-120). A high T/B was related to a large fraction of tumor cells in lymph node metastases. T/Bs were higher for the tumor samples with expression of sstr2 at Northern blot analysis than for those without. All thyroid tumor types regularly expressed sstr1, sstr3, sstr4, and sstr5. sstr2 was expressed in most MTC tumors but was not detected in FA or PC and was irregularly expressed in HCA and HCC. However, RPA analysis detected sstr2 in all tumors studied. CONCLUSION: Despite the lack of sstr2 at Northern blot analysis in most of the thyroid tumors studied, high T/Bs were in general found when compared with corresponding values for normal thyroid tissue. The sometimes extremely high ratios are promising and indicate a possibility of using radiolabeled octreotide for radiation therapy of sstr-positive tumors in the future.