Håkan Ahlman

Pheochromocytoma: Recommendations for clinical practice from the First International Symposium

The First International Symposium on Pheochromocytoma, held in October 2005, included discussions about developments concerning these rare catecholamine-producing tumors. Recommendations were made during the symposium for biochemical diagnosis, localization, genetics, and treatment. Measurement of plasma or urinary fractionated metanephrines, the most accurate screening approach, was recommended as the first-line test for diagnosis; reference intervals should favor sensitivity over specificity. Localization studies should only follow reasonable clinical evidence of a tumor. Preoperative pharmacologic blockade of circulatory responses to catecholamines is mandatory. Because approximately a quarter of tumors develop secondary to germ-line mutations in any one of five genes, mutation testing should be considered; however, it is not currently cost effective to test every gene in every patient. Consideration of tumor location, presence of multiple tumors, presence of metastases, and type of catecholamine produced is useful in deciding which genes to test. Inadequate methods to distinguish malignant from benign tumors and a lack of effective treatments for malignancy are important problems requiring further resolution.

Guidelines for the diagnosis and treatment of neuroendocrine gastrointestinal tumours. A consensus statement on behalf of the European Neuroendocrine Tumour Society (ENETS).

Guidelines for the diagnosis and treatment of neuroendocrine gastrointestinal tumours. A consensus statement on behalf of the European Neuroendocrine Tumour Society (ENETS).

Consensus guidelines for the management of patients with liver metastases from digestive (neuro)endocrine tumors: Foregut, midgut, hindgut, and unknown primary

a DRK Kliniken Westend, Berlin , Germany; b UFR Bichat-Beaujon-Louis Mourier, Service de Chirurgie Digestive, Hopital Louis Mourier, Colombes , France; c Medicine and Surgery, General Surgery Section, MED/18 – General Surgery and d Department of Pathology, University of Verona, Verona , Italy; e Netherlands Cancer Centre, Amsterdam , and f Department of Nuclear Medicine, Erasmus University Medical Center, Rotterdam , The Netherlands;

Consensus guidelines for the management of patients with digestive neuroendocrine tumors - Well-differentiated jejunal-ileal tumor/carcinoma

Consensus guidelines for the management of patients with digestive neuroendocrine tumors : well-differentiated jejunal-ileal tumor/carcinoma

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.

Well-differentiated gastric tumors/carcinomas

a Department of Gastroenterology, Beaujon Hospital, Clichy , France; b Department of Digestive and Liver Disease, Ospedale S. Andrea, Rome , Italy; c Department of Hepatology and Gastroenterology, CHU Bichat – B. Claude Bernard University, Paris , France; d Department of Pathology, Kantonsspital Baden , Switzerland; e Department of Gastroenterology, Massachussetts General Hospital, Boston , Mass. , USA; f B. Kos-Kudla, Department of Endocrinology, Slaska University, Zabrze , Poland; g Department of Surgery, UFR Bichat-Beaujon-Louis Mourier Hospital, Colombes , France; h Department of Oncology, Royal Free University, London , UK; i Department of Gastroenterology, Philipps University, Marburg , Germany; j Department of Surgery, Gothenburg University, Gothenburg , Sweden; k Department of Nuclear Medicine, Catholique de Louvain University, Brussels , Belgium; l Department of Nuclear Medicine, Erasmus MC University, Rotterdam , The Netherlands; m Department of Pathology and Laboratory Medicine, Universita degli Studi, Parma , Italy

Adjuvant imatinib treatment improves recurrence-free survival in patients with high-risk gastrointestinal stromal tumours (GIST)

Palliative imatinib treatment has dramatically improved survival in patients with malignant gastrointestinal stromal tumours, particularly in patients with tumours harbouring activating KIT mutations. To evaluate the effectiveness of adjuvant imatinib after radical surgery, a consecutive series of patients with high-risk tumours (n=23) was compared with historic controls (n=48) who were treated with surgery alone. The mean follow-up period was over 3 years in both groups. Only 1 out of 23 patients (4%) in the adjuvant treatment group developed recurrent disease compared to 32 out of 48 patients (67%) in the control group. This preliminary study indicates that 1 year of adjuvant treatment with imatinib dramatically improves recurrence-free survival. Confirmation of these findings awaits the results of ongoing randomised studies.

Orthotopic liver or multivisceral transplantation as treatment of metastatic neuroendocrine tumors

Liver transplantation can be a therapeutic option for individual patients with neuroendocrine tumors metastatic only to the liver. In this consecutive series of 15 patients (5 multivisceral and 10 orthotopic liver transplantations) with well‐differentiated carcinoids, or endocrine pancreatic tumors, we allowed higher proliferation rate (Ki67 <10%), large tumor burden, and higher age than previous studies. Liver transplantation offered good relief of symptoms, long disease‐free intervals, and potential cure in individual patients. The survival of grafts and patients compared well with transplantation for benign disease. The overall 5‐year survival was 90%. The recurrence‐free survival of both multivisceral and liver transplantation related to the time after transplantation (about 20% at 5 years) despite inclusion of patients with higher risk. In conclusion, the critical prognosticators for long‐term outcome still remain to be defined. The experience with multivisceral transplantation for patients with endocrine tumors of the pancreatic head is still limited. Liver Transpl 13:327–333, 2007.

Specific growth rate versus doubling time for quantitative characterization of tumor growth rate.

Doubling time (DT) is widely used for quantification of tumor growth rate. DT is usually determined from two volume estimations with measurement time intervals comparable with or shorter than DT. Clinical data show that the frequency distribution of DT in patients is positively skewed, with some very long DT values compared with the average DT. Growth rate can also be quantified using specific growth rate (SGR; %/d), equal to ln2/DT. The aim of this work was to compare DT and SGR as growth rate variables. Growth rate calculations were computer simulated for a tumor with DT of 100 days, measurement time interval of 1 to 200 days, and volume estimation uncertainty of 5% to 20%. Growth rate variables were determined and compared for previously published clinical data. The study showed that DT is not a suitable variable for tumor growth rate because (a) for short measurement time intervals, or high volume uncertainties, mean DT can either overestimate or underestimate the average growth rate; (b) DT is not defined if the consecutively estimated volumes are equal; and (c) the asymmetrical frequency distribution of DT makes it unsuitable for common statistical testing. In contrast, mean SGR and its equivalent DT give the correct values for average growth rate, SGR is defined for all tumor volume changes, and it has a symmetrical frequency distribution. SGR is also more accurate to use when discussing, for example, growth fraction, cell loss rate, and growth rate heterogeneities within the tumor. SGR should thus be used, instead of DT, to quantify tumor growth rate.

Comparative studies on the expression of somatostatin receptor subtypes, outcome of octreotide scintigraphy and response to octreotide treatment in patients with carcinoid tumours

We have compared the expression of somatostatin receptor (sstr) subtypes with the outcome of somatostatin receptor scintigraphy and the effect of somatostatin receptor activation in patients with disseminated carcinoid tumours. Tumour tissues from nine patients with midgut carcinoids (ileal) and three patients with foregut carcinoids (gastric, thymic) were analysed using Northern blotting. Expression of somatostatin receptors was demonstrated in all tumours (12 out of 12), with all five receptor subtypes present in 9 out of 12 tumours. Somatostatin receptor scintigraphy using [111In]DTPA-D-Phe1-octreotide visualized tumours in all patients (12 out of 12). The 111In activity concentrations in tumour tissue (T) and blood (B) were determined in three tumours 1-7 days after injection of the radionuclide. The T/B 111In activity concentration ratios ranged between 32 and 651. Clinically, treatment with the long-acting somatostatin analogue octreotide resulted in marked symptom relief accompanied by a significant reduction in tumour markers, for example urinary-5-HIAA levels (28-71% reduction). Incubation of midgut carcinoid tumours in primary culture with octreotide (10 microM) resulted in a reduction in spontaneously secreted serotonin (45-71% reduction) and 5-HIAA (41-94% reduction). The results demonstrate that carcinoid tumours possess multiple somatostatin receptor subtypes and that somatostatin analogues such as octreotide, which preferentially bind to somatostatin receptor subtype 2 and 5, can be used in the diagnosis and medical treatment of these tumours. In the future, novel somatostatin analogues with subtype specific receptor profiles may prove to be of value for individualizing the treatment of disseminated carcinoid tumour disease.