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H Ahlman

Publications and source records attributed to H Ahlman.

At least 19 recordsLinked to original sources
PubMed2006

Population-based study of the diagnosis and treatment of gastrointestinal stromal tumours.

BACKGROUND: The aim of this retrospective population-based study, which was conducted before the introduction of imatinib, was to evaluate the role of surgery in patients with gastrointestinal stromal tumours (GISTs) and clarify which subgroups might benefit from adjuvant treatment. METHODS: Two hundred and fifty-nine patients with clinically detected GISTs were studied. Univariate and multivariate analyses were performed to identify predictors for recurrent disease and survival. RESULTS: Thirty of 48 patients with high-risk GISTs and all of those with overtly malignant tumours developed recurrent tumour after complete (R0) resection. Thirty-four of 38 first recurrences occurred within 36 months of surgery. No recurrence was observed after 72 months. R0 resection, achieved in 48 (80 per cent) of 60 patients with high-risk tumours, was significantly associated with a decreased risk of death from tumour recurrence (P = 0.008). CONCLUSION: Completeness of surgical resection is an independent prognostic factor in patients with high-risk GISTs. A period of adjuvant treatment with imatinib is recommended in patients with high-risk or overtly malignant GISTs who have undergone R0 resection and have a tumour-free interval of less than 6 years.

Adolescent↗
PubMed2005

Successful receptor-mediated radiation therapy of xenografted human midgut carcinoid tumour.

Somatostatin receptor (sstr)-mediated radiation therapy is a new therapeutic modality for neuroendocrine (NE) tumours. High expression of sstr in NE tumours leads to tumour-specific uptake of radiolabelled somatostatin analogues and high absorbed doses. In this study, we present the first optimised radiation therapy via sstr using [(177)Lu-DOTA(0)-Tyr(3)]-octreotate given to nude mice xenografted with the human midgut carcinoid GOT1. The tumours in 22 out of 23 animals given therapeutic amounts showed dose-dependent, rapid complete remission. The diagnostic amount (0.5 MBq [(177)Lu-DOTA(0)-Tyr(3)]-octreotate) did not influence tumour growth and was rapidly excreted. In contrast, the therapeutic amount (30 MBq [(177)Lu-DOTA(0)-Tyr(3)]-octreotate) induced rapid tumour regression and entrapment of (177)Lu so that the activity concentration of (177)Lu remained high, 7 and 13 days after injection. The entrapment phenomenon increased the absorbed dose to tumours from 1.6 to 4.0 Gy MBq(-1) and the tumours in animals treated with 30 MBq received 120 Gy. Therapeutic amounts of [(177)Lu-DOTA(0)-Tyr(3)]-octreotate rapidly induced apoptosis and gradual development of fibrosis in grafted tumours. In conclusion, human midgut carcinoid xenografts can be cured by receptor-mediated radiation therapy by optimising the uptake of radioligand and taking advantage of the favourable change in biokinetics induced by entrapment of radionuclide in the tumours.

Animals↗
PubMed2005

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.

Adrenal Gland Neoplasms↗
PubMed2004

Phenotypic expression of a family with multiple endocrine neoplasia type 2A due to a RET mutation at codon 618.

BACKGROUND: Multiple endocrine neoplasia type 2A (MEN2A) is caused by missense mutations in the RET proto-oncogene on chromosome 10. This paper reports the phenotypic expression of a family with MEN2A, in which serine substitutes for cysteine at codon 618 in exon 10 of the RET gene. It was first claimed that medullary thyroid cancer (MTC) with this rare mutation led to mild disease; this has recently been updated to intermediate-high risk, based on stratified genetic information. METHODS: The family was mapped over six generations. In 1971 family members were invited to join a screening programme. Genetic testing was started in 1994. RESULTS: Twenty-two individuals with MTC were identified, 16 by the screening programme. One screened patient had a phaeochromocytoma and four had hyperparathyroidism. At surgery for MTC 12 patients had local tumour metastases and two young patients also had liver metastases. No screened patient died from MTC during a mean observation time of 19 years. Six other family members were diagnosed with MTC by signs and symptoms, five of whom died from MTC. CONCLUSION: Because of the great interindividual differences in tumour aggressiveness within the family it is impossible to predict whether an individual gene carrier will have an aggressive MTC or not. This unpredictability is an additional argument, besides those obtained in stratified genetic studies, for operating on gene carriers at young age.

Adolescent↗
PubMed2004

Mortality associated with pheochromocytoma in a large Swedish cohort.

BACKGROUND: The aim of the present study was to report the risk of death in a national cohort of patients with aPC (adrenal PC) and their risk of developing a second tumour. METHODS: Using the National Cancer Registry, 481 patients (222 men and 259 women) with aPC in Sweden (1958-1997) were identified. Autopsy-based diagnoses were excluded. As control group the entire Swedish population was used and the risk of death in patients after diagnosis of aPC was compared with the normal risk taking age, sex and calendar year into account. The risk for a second tumour disease after diagnosis of aPC was also calculated. RESULTS: Patients with aPC had an increased tumour-related mortality after diagnosis of aPC. For both men and women this mortality was four times higher than for controls. Liver/biliary tract and CNS tumours in men; and malignant melanoma and uterine cervical cancer in women were significantly over-represented in the cohort of patients with aPC. CONCLUSION: Patients with aPC run an increased risk of developing additional cancers. Surveillance strategies may thus be necessary for these patients.

Adolescent↗
PubMed2004

Interventional treatment of the carcinoid syndrome.

Liver metastases imply a major problem in patients with carcinoid tumours and hormone overproduction. Patients with distant metastases can undergo resection for potential cure or for symptom palliation. In patients with bilobar liver metastases other interventions are at hand, e.g. local ablation or hepatic arterial embolization. In selected cases liver transplantation can be a treatment alternative. Prior to all interventions patients with midgut carcinoids are protected with somatostatin analogues to reduce hormone secretion. Patients with foregut carcinoids may present special problems with life-threatening release of histamine during interventions.

Carcinoid Tumor↗
PubMed2003

The Ki67 index a prognostic marker in medullary thyroid carcinoma.

Our objective was to examine the usefulness of the Ki67 proliferation index as a prognostic marker in patients with medullary thyroid carcinoma (MTC). It is difficult to predict the prognosis of MTC by using conventional prognostic factors. Immunocytochemical analysis of tumour proliferation has been used as a prognostic tool in some tumours, but only rarely in MTC. In all, 71 tumours from 36 patients were investigated, by using a semiautomatic image analysis programme. On average 10,000 nuclear profiles were counted per tumour, and the percentage of tumour cells expressing the proliferation marker, Ki67, was calculated. Primary tumours that had metastasised had higher Ki67 indices than primary tumours that had not metastasised. Recurrent lymph node metastasis had higher Ki67 indices than the primary tumours. By using a Poisson model, it was possible to estimate the median survival time for individual patients if the Ki67 index for the primary tumour and the age at surgery were known. The higher the Ki67 index and the age at operation were, the shorter was the survival. Estimating the median survival of individual patients will be of help for planning the patients' life and postoperative follow-up and treatment.

Adult↗
PubMed2003

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.

3-Iodobenzylguanidine↗
PubMed2003

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.

Adult↗
PubMed2003

NESP55, a novel chromogranin-like peptide, is expressed in endocrine tumours of the pancreas and adrenal medulla but not in ileal carcinoids.

Neuroendocrine secretory protein 55, NESP55, is an acidic protein belonging to the chromogranin family. The distribution of NESP55 in human tumours is not known. The aim of the present study was to study the expression of NESP55 in human gastrointestinal, pancreatic and adrenal tumours. A total of 118 human endocrine and nonendocrine tumours were examined by immunocytochemistry, and compared to the expression of chromogranin A (CgA) in the same tumours. Pancreatic endocrine tumours (14 out of 25), pheochromocytomas (19 out of 19), and neuroblastomas (seven out of 14) expressed NESP55, with the same strong labelling pattern in both benign and malignant tumours. Expression of NESP55 in pancreatic endocrine tumours and pheochromocytomas was confirmed by Western and Northern blot analysis. Immunocytochemical analysis demonstrated no labelling in ileal carcinoids (zero out of 15), and adrenocortical adenomas (zero out of 15). The majority of gastrointestinal and pancreatic carcinomas were negative for NESP55, with focal staining observed in two out of 30 tumours. In contrast, CgA was present in all neuroendocrine tumours examined (25 out of 25 pancreatic endocrine tumours, 19 out of 19 pheochromocytomas, 14 out of 14 neuroblastomas and 15 out of 15 ileal carcinoids). Thus, the expression of NESP55 in endocrine tumours of the gastrointestinal tract, pancreas and adrenals differs from that of CgA. Neuroendocrine secretory protein 55 is found in a subset of neuroendocrine tumours showing differentiation towards adrenal chromaffin cells and pancreatic islets cells.

Adolescent↗
PubMed2003

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.

Adult↗
PubMed2001

Dosimetric comparison of radionuclides for therapy of somatostatin receptor-expressing tumors.

PURPOSE: Therapy of tumors expressing somatostatin receptors, sstr, has recently been clinically tested using somatostatin analogues labeled with (111)In and (90)Y. Several other radionuclides, i.e., (131)I, (161)Tb, (64)Cu, (188)Re, (177)Lu, and (67)Ga, have also been proposed for this type of therapy. The aim of this work was to investigate the usefulness of the above-mentioned radionuclides bound to somatostatin analogues for tumor therapy. METHODS: Biokinetic data of (111)In-labeled octreotide in mice and man were used, primarily from our studies but sometimes from the literature. Dosimetric calculations were performed with the assumption that biokinetics were similar for all radionuclides bound to somatostatin analogues. The cumulated tumor:normal-tissue activity concentration, TNC was calculated for the various physical half-lives of the radionuclides. Using mathematical models, the tumor:normal-tissue mean absorbed dose rate ratio, TN D and tumor:normal-tissue mean absorbed dose ratio, TND, were calculated for various tumor sizes in mice and humans. RESULTS: TNC of radionuclide-labeled octreotide increased with physical half-life for most organs, both in mice and in humans. TN D showed that radionuclides emitting electrons with too high energy are not suitable for therapy of small tumors. Furthermore, radionuclides with a higher frequency of photon emissions relative to electron emissions will yield lower TN D and are thus less suitable for therapy than radionuclides with a lower frequency of photon emissions. The TND was highest for (161)Tb in both mice and humans. CONCLUSIONS: The results demonstrate that long-lived radionuclides, which emit electrons with rather low energy and which have low frequency of photon emissions, should be the preferred therapy for disseminated small sstr-expressing tumors.

Algorithms↗
PubMed2001

[Phenotypic expression of a mutation in MEN 2A documented in a family in the western part of Sweden].

A missense mutation at codon 618 of the RET proto-oncogene is a rather unusual cause of multiple endocrine neoplasia 2A. We report the phenotypic expression of this specific RET mutation in a large Swedish family. The family was mapped back to the 18th century. Since 1971 the family has been included in a biochemical screening program, and since 1994 has undergone genetic screening. Twenty-seven individuals were found to have medullary thyroid carcinoma (MTC). Eighteen were detected by screening. The incidence of pheochromocytoma (4%) and hyperparathyroidism (7%) was low. Five individuals died of MTC, but of these none had been included in the screening program. One patient underwent prophylactic thyroidectomy after positive genetic screening. MTC tumor aggressivity differed markedly between gene carriers. The screening program shows that the clinical aggressivity of MTC can be mitigated by early and adequate surgical intervention.

Female↗
PubMed2001

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.

Blotting, Western↗