Thomas J. Musholt

Minimally Invasive Versus Open Esophagectomy: Meta-Analysis of Outcomes

BackgroundA meta-analysis of the current literature was performed to compare the perioperative outcome measures and oncological impact between minimally invasive and open esophagectomy.MethodsUsing the electronic databases Medline, Embase, Pubmed and the Cochrane Library, we performed a meta-analysis pooling the effects of outcomes of 1,008 patients enrolled into eight comparative studies, using classic and modern meta-analytic methods.ResultsTwo comparisons were considered for this systematic review: (I) open thoracotomy vs. VATS/laparoscopy esophagectomy and (II) open thoracotomy vs. VATS esophagectomy. In comparison I: both procedures report equally comparable outcomes (removed lymph nodes, 30-day mortality, 3-year survival) with the exception of overall morbidity (Pxa0=xa00.038; in favor of the MIE arm) and anastomotic stricture (Pxa0<xa00.001; in favor of the open thoracotomy arm). In comparison II: No differences were noted between treatment arms concerning postoperative outcomes and survival.ConclusionsIn summary, both arms were comparable with regard to perioperative results and prognosis. Further prospective comparative or randomized-controlled trials focusing on the oncological impact of MIE are needed.

Somatostatin-producing neuroendocrine tumors of the duodenum and pancreas: incidence, types, biological behavior, association with inherited syndromes, and functional activity

Somatostatin-producing neuroendocrine tumors (SOM-NETs) of the duodenum and pancreas appear to be heterogeneous. To determine their clinicopathological profiles, respective data were analyzed on a series of 82 duodenal and 541 pancreatic NETs. In addition, the clinical records of 821 patients with duodenal or pancreatic NETs were reviewed for evidence of a somatostatinoma syndrome. Predominant or exclusive expression of somatostatin was found in 21 (26%) duodenal and 21 (4%) pancreatic NETs. They were classified as sporadic (n=31) or neurofibromatosis type 1 (NF1)-associated duodenal NETs (n=3), gangliocytic paragangliomas (GCPGs; n=6), or poorly differentiated neuroendocrine carcinomas (pdNECs; n=2). In addition, five duodenal and four pancreatic SOM-NETs were found in five patients with multiple endocrine neoplasia type 1 (MEN1). Metastases occurred in 13 (43%) patients with sporadic or NF1-associated SOM-NETs, but in none of the duodenal or pancreatic MEN1-associated SOM-NETs or GCPGs. Sporadic advanced (stage IV) SOM-NETs were more commonly detected in the pancreas than in the duodenum. None of the patients (including the 821 patients for whom only the clinical records were reviewed) fulfilled the criteria of a somatostatinoma syndrome. Our data show that somatostatin expression is not only seen in sporadic NETs but may also occur in GCPGs, pdNECs, and hereditary NETs. Surgical treatment is effective in most duodenal and many pancreatic SOM-NETs. MEN1-associated SOM-NETs and GCPGs follow a benign course, while somatostatin-producing pdNECs are aggressive neoplasms. The occurrence of the so-called somatostatinoma syndrome appears to be extremely uncommon.

6-18F-fluoro-L-dihydroxyphenylalanine positron emission tomography is superior to 123I-metaiodobenzyl-guanidine scintigraphy in the detection of extraadrenal and hereditary pheochromocytomas and paragangliomas: correlation with vesicular monoamine transporter expression.

CONTEXTnPheochromocytomas (PHEOs) and paragangliomas (PGLs) may be better detected by (18)F-fluorodihydroxyphenylalanine-positron emission tomography (FDOPA-PET) than (123)I-metaiodobenzyl-guanidine (123-I-MIBG) scintigraphy.nnnOBJECTIVEnThe objective of the study was to correlate functional imaging results with immunohistochemical, molecular-genetic, and biochemical findings.nnnDESIGN AND SETTINGnThirty consecutive patients with suspected PHEO/PGL presenting at a tertiary referral centre were investigated in a prospective study.nnnPATIENTSnTwenty-five patients had confirmed PHEO/PGL. Thirteen of 25 patients had a hereditary PHEO/PGL syndrome (two multiple endocrine neoplasia II, six succinate dehydrogenase complex, subunit D, two succinate dehydrogenase complex, subunit B, one von Hippel Lindau tumor suppressor protein, two Neurofibromatosis-1), and 12 of 25 were classified as sporadic. Five patients had hormonally inactive adrenal incidentalomas.nnnMAIN OUTCOME MEASURESnIn all patients computed tomography scan and/or magnetic resonance imaging as well as both 123-I-MIBG scintigraphy and FDOPA-PET were performed. Resected tumors were examined by immunohistochemistry for expression of the vesicular monoamine transporter (VMAT)-1 and -2 and other markers.nnnRESULTSnA total of 64 lesions were found with both functional imaging modalities. FDOPA-PET detected 62 lesions, whereas only 34 lesions were detected by 123-I-MIBG scintigraphy. This resulted in an overall sensitivity and specificity for FDOPA-PET of 98 and 100% and for MIBG of 53 and 91%, respectively. Comparable sensitivities were found for adrenal and extraadrenal abdominal lesions (94 vs. 97%), whereas in thoracic/cervical lesions, the sensitivity for 123-I-MIBG scintigraphy (15%) was inferior to that of FDOPA-PET imaging (100%). Immunohistochemistry demonstrated a lack of VMAT-1 expression in all MIBG-negative tumors. Clinical predictors for MIBG negativity were a predominant norepinephrine/normetanephrine secretion, an age less than 45 yr, and a hereditary cause.nnnCONCLUSIONnFDOPA-PET is superior to 123-I-MIBG scintigraphy in patients with extraadrenal, predominantly noradrenaline-secreting, and hereditary types of PHEO/PGL. The lack of VMAT-1 expression predicts negativity for MIBG-scintigraphy.

Risk Profiles and Penetrance Estimations in Multiple Endocrine Neoplasia Type 2A Caused by Germline RET Mutations Located in Exon 10

Multiple endocrine neoplasia type 2 is characterized by germline mutations in RET. For exon 10, comprehensive molecular and corresponding phenotypic data are scarce. The International RET Exon 10 Consortium, comprising 27 centers from 15 countries, analyzed patients with RET exon 10 mutations for clinical‐risk profiles. Presentation, age‐dependent penetrance, and stage at presentation of medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism were studied. A total of 340 subjects from 103 families, age 4–86, were registered. There were 21 distinct single nucleotide germline mutations located in codons 609 (45 subjects), 611 (50), 618 (94), and 620 (151). MTC was present in 263 registrants, pheochromocytoma in 54, and hyperparathyroidism in 8 subjects. Of the patients with MTC, 53% were detected when asymptomatic, and among those with pheochromocytoma, 54%. Penetrance for MTC was 4% by age 10, 25% by 25, and 80% by 50. Codon‐associated penetrance by age 50 ranged from 60% (codon 611) to 86% (620). More advanced stage and increasing risk of metastases correlated with mutation in codon position (609→620) near the juxtamembrane domain. Our data provide rigorous bases for timing of premorbid diagnosis and personalized treatment/prophylactic procedure decisions depending on specific RET exon 10 codons affected. Hum Mutat 31:1–8, 2010.

Differential Clinicopathological Risk and Prognosis of Major Papillary Thyroid Cancer Variants

CONTEXTnIndividualized management, incorporating papillary thyroid cancer (PTC) variant-specific risk, is conceivably a useful treatment strategy for PTC, which awaits comprehensive data demonstrating differential risks of PTC variants to support.nnnOBJECTIVEnThis study sought to establish the differential clinicopathological risk of major PTC variants: conventional PTC (CPTC), follicular-variant PTC (FVPTC), and tall-cell PTC (TCPTC).nnnMETHODSnThis was a retrospective study of clinicopathological outcomes of 6282 PTC patients (4799 females and 1483 males) from 26 centers and The Cancer Genome Atlas in 14 countries with a median age of 44 years (interquartile range, 33-56 y) and median follow-up time of 37 months (interquartile range, 15-82 mo).nnnRESULTSnThe cohort consisted of 4702 (74.8%) patients with CPTC, 1126 (17.9%) with FVPTC, and 239 (3.8%) with TCPTC. The prevalence of high-risk parameters was significantly different among the three variants, including extrathyroidal invasion, lymph node metastasis, stages III/IV, disease recurrence, mortality, and the use (need) of radioiodine treatment (all P < .001), being highest in TCPTC, lowest in FVPTC, and intermediate in CPTC, following an order of TCPTC > CPTC ≫ FVPTC. Recurrence and mortality in TCPTC, CPTC, and FVPTC were 27.3 and 6.7%, 16.1 and 2.5%, and 9.1 and 0.6%, corresponding to events per 1000 person-years (95% confidence interval [CI]) of 92.47 (64.66-132.26) and 24.61 (12.31-49.21), 34.46 (30.71-38.66), and 5.87 (4.37-7.88), and 24.73 (18.34-33.35) and 1.68 (0.54-5.21), respectively. Mortality hazard ratios of CPTC and TCPTC over FVPTC were 3.44 (95% CI, 1.07-11.11) and 14.96 (95% CI, 3.93-56.89), respectively. Kaplan-Meier survival analyses showed the best prognosis in FVPTC, worst in TCPTC, and intermediate in CPTC in disease recurrence-free probability and disease-specific patient survival. This was particularly the case in patients at least 45 years old.nnnCONCLUSIONnThis large multicenter study demonstrates differential prognostic risks of the three major PTC variants and establishes a unique risk order of TCPTC > CPTC ≫ FVPTC, providing important clinical implications for specific variant-based management of PTC.

Comparison between minimally invasive video-assisted thyroidectomy and conventional thyroidectomy: is there any evidence-based information?

BACKGROUNDnThe aim of this study was to test the hypothesis that minimally invasive video-assisted thyroidectomy (MIVAT) affords comparable safety and efficacy as to the open conventional surgery in dealing with patients with small thyroid nodules.nnnMETHODSnRandomized controlled trials comparing the MIVAT with open thyroidectomy were ascertained by methodical search using Medline, Embase, Pubmed, and The Cochrane Library. Primary meta-analysis outcomes were adverse events (laryngeal nerve palsy and hypoparathyroidism), and cosmesis and secondary outcomes were operative time, blood loss, and early and late postoperative pain.nnnRESULTSnOperative time was significantly less with open thyroidectomy than with MIVAT, while MIVAT was associated with less pain at 6 hours postoperatively. Blood loss did not reached significance between procedures. Comparisons between two procedures concerning pain score of 24 and 48 hours, respectively, depicted statistically significant differences in favor of the MIVAT but only in the fixed effects model. MIVAT was associated with less scarring. There were no statistically significant differences for the presence of transient recurrent laryngeal nerve palsy and the presence of transient hypoparathyroidism.nnnCONCLUSIONSnMIVAT is a safe procedure that produces outcomes; in view of short-term adverse events, similar to those of open thyroidectomy, it needs a longer operative time to be accomplished and is superior in terms of immediate postoperative pain and cosmetic results.

Adrenalectomy for solid tumor metastases: Results of a multicenter European study

BACKGROUNDnWe assessed the results of adrenalectomy for solid tumor metastases in 317 patients recruited from 30 European centers.nnnMETHODSnPatients with histologically proven adrenal metastatic disease and undergoing complete removal(s) of the affected gland(s) were eligible.nnnRESULTSnNon-small cell lung cancer (NSCLC) was the most frequent tumor type followed by colorectal and renal cell carcinoma. Adrenal metastases were synchronous (≤6 months) in 73 (23%) patients and isolated in 213 (67%). The median disease-free interval was 18.5 months. Laparoscopic resection was used in 46% of patients. Surgery was limited to the adrenal gland in 73% of patients and R0 resection was achieved in 86% of cases. The median overall survival was 29 months (95% confidence interval, 24.69-33.30). The survival rates at 1, 2, 3, and 5 years were 80%, 61%, 42%, and 35%, respectively. Patients with renal cancer showed a median survival of 84 months, patients with NSCLC 26 months, and patients with colorectal cancer 29 months (P = .017). Differences in survival between metachronous and synchronous lesions were also significant (30 vs. 23 months; P = .038).nnnCONCLUSIONnSurgical removal of adrenal metastasis is associated with long-term survival in selected patients.

Differential miRNA expression defines migration and reduced apoptosis in follicular thyroid carcinomas.

The objective of the study was to identify microRNAs (miRs) characteristic for follicular thyroid carcinoma (FTC) and to define their role in tumorigenesis. A miR-microarray study was conducted to identify miRs differentially expressed between FTCs and their surrounding tissues. Selection was further reinforced by a literature review. Four miRs were selected and confirmed by RT-qPCR: miR-146b, -183, -221 were up-regulated, whereas miR-199b down-regulated in FTCs. The influence of these miRs on cell proliferation, cell cycle, apoptosis and migration was studied in HTori and FTC-133 cells. Functional characterization suggests an impact of miR-183 and miR-146b in FTC development. Overexpression of both miRs significantly induces migration. Moreover, overexpression of miR-183 significantly represses apoptosis. MiR-199b and -221 do not have significant effects on proliferation, cell cycle, apoptosis or migration in HTori and FTC-133 cells. Our data suggest that miR-146b and miR-183 may influence FTC development through the induction of migration and apoptosis inhibition.

Oncofoetal fibronectin--a tumour-specific marker in detecting minimal residual disease in differentiated thyroid carcinoma.

Supposedly, thyrocyte-specific transcripts such as thyroglobulin (Tg) and thyroid-stimulating hormone receptor (TSH-R) were proposed to be useful for the diagnosis of circulating tumour cells in patients suffering from differentiated thyroid carcinoma (DTC). However, several research groups reported blood-borne Tg transcripts in healthy individuals. This study determines in particular the origin of Tg mRNA in nucleated blood cells and analyses whether other tumour-associated sequences are absent in leukocytes, but widely expressed in DTC. Therefore, expression analyses for Tg, TSH-R, cytokeratin 19 (CK 19), human telomerase reverse transcriptase (hTERT) and oncofoetal fibronectin (onfFN) were carried out using cDNAs derived from (1) leukocyte fractions, (2) 18 follicular thyroid carcinomas (FTCs) and 48 papillary thyroid carcinomas (PTCs), and (3) leukocytes of two thyrocyte-depleted individuals treated for C-cell carcinoma of the thyroid. Expression of onfFN was additionally analysed by semiquantitative RT–PCR and by quantitative fluorescence-based real-time PCR. Tg and TSH-R expression was demonstrated not only in both athyroid individuals, but in all leukocyte subgroups tested, while hTERT was absent in resting CD4+ cells and only weakly expressed in the CD8+ group. CK 19 was notable in each leukocyte population except for resting CD14+, as well as for activated and resting CD19+ cells. All blood cell fractions proved negative for onfFN mRNA, whereas its presence in thyroid carcinoma was 78/98% (FTC/PTC). Threshold cycle values were calculated at: porphobilinogen deaminase (PBGD) =25.95±0.73 (FTC)/24.55±5.43 (PTC) (P=0.2878); onfFN=25.48±3.15 (FTC)/21.44±3.44 (PTC) (*P=0.0001). Finally, onfFN transcripts were detected in blood samples of six out of nine patients with known DTC metastases, demonstrating a reliable assay functionality. We propose that real-time RT–PCR of onfFN mRNA is superior to other markers in monitoring minimal residual disease in DTC with regard to both assay sensitivity and specificity.

Impact of pathognomonic genetic alterations on the prognosis of papillary thyroid carcinoma

IntroductionBRAF mutations and RET or NTRK1 rearrangements were identified as causing events that drive the malignant transformation of the thyroid follicular cell. The impact of these alterations on the course of papillary thyroid carcinoma (PTC) is still unsettled.Patients and methodsTumor tissues of 290 (98 male, 192 female) patients were intra-operatively snap frozen or harvested from archival paraffin-embedded blocks and used for extraction of DNA and RNA. Comprehensive analysis of RET/PTC and NTRK1 rearrangements was carried out by multiplex screening RT-PCR, hybrid-specific RT-PCR and sequencing of detected hybrids. A mutation-specific PCR was used for BRAF analysis.ResultsThe BRAF V600E mutation was detected in 122/290 (42%), RET rearrangements in 20/137 (14.6%), and NTRK1 rearrangements in 15/93 (16.1%) PTCs. One hundred forty one out of 290 (48.6%) PTCs demonstrated none of the genetic alterations studied. Eight PTCs expressed two different mutations (1 RET/PTCu2009+u2009BRAF, 6 NTRK1u2009+u2009BRAF, 1 RET/PTCu2009+u2009NTRK1). Tumor-specific survival analysis (mean follow-up, 5.5xa0years) demonstrated no significant difference, but a tendency toward worse prognosis of BRAF-positive patients compared to BRAF-negative patients or rearrangement-positive patients, respectively.ConclusionLong-term follow-up data on large tumor panels are needed to disclose significant survival differences of prognostic predictors on PTC. This study provides further evidence that patients harboring BRAF-V600E-positive PTCs may experience an unfavorable course of the disease compared to patients with tumors carrying other genetic alterations.