Theofanis Economopoulos

Studies of insulin resistance in patients with clinical and subclinical hyperthyroidism

OBJECTIVE Although clinical hyperthyroidism (HR) is associated with insulin resistance, the information on insulin action in subclinical hyperthyroidism (SHR) is limited. DESIGN AND METHODS To investigate this, we assessed the sensitivity of glucose metabolism to insulin in vivo (by an oral glucose tolerance test) and in vitro (by measuring insulin-stimulated rates of glucose transport in isolated monocytes) in 12 euthyroid subjects (EU), 16 patients with HR, and 10 patients with SHR. RESULTS HR and SHR patients displayed higher postprandial glucose levels (area under the curve, AUC(0)(-)(300) 32,190±1067 and 31,497±716,mg/dl min respectively) versus EU (27,119±1156 mg/dl min, P<0.05). HR but not SHR patients displayed higher postprandial insulin levels (AUC(0)(-)(300) 11,020±985 and 9565±904 mU/l min respectively) compared with EU subjects (AUC(0)(-)(300) 7588±743 mU/l min, P<0.05). Homeostasis model assessment index was increased in HR and SHR patients (2.81±0.3 and 2.43±0.38 respectively) compared with EU subjects (1.27±0.16, P<0.05), while Matsuda and Belfiore indices were decreased in HR (4.21±0.41 and 0.77±0.05 respectively, P<0.001) and SHR patients (4.47±0.33 and 0.85±0.05 respectively, P<0.05 versus EU (7.76±0.87 and 1 respectively). At 100 μU/ml insulin, i) GLUT3 levels on the monocyte plasma membrane were increased in HR (468.8±7 mean fluorescence intensity (MFI)) and SHR patients (522.2±25 MFI) compared with EU subjects (407±18 MFI, P<0.01 and P<0.05 respectively), ii) glucose transport rates in monocytes (increases from baseline) were decreased in HR patients (37.8±5%) versus EU subjects (61.26±10%, P<0.05). CONCLUSIONS Insulin-stimulated glucose transport in isolated monocytes of patients with HR was decreased compared with EU subjects. Insulin resistance was comparable in patients with both HR and SHR.

Improved survival of patients with multiple myeloma after the introduction of novel agents and the applicability of the International Staging System (ISS): an analysis of the Greek Myeloma Study Group (GMSG).

When the novel agents thalidomide, bortezomib and lenalidomide are administered to patients with myeloma in the context of clinical trials, they are associated with a significant improvement in response, progression-free survival and in some studies, overall survival (OS); however, their effect on the outcome of unselected myeloma patients has not been fully assessed. We compared the outcome of 1376 unselected patients with symptomatic myeloma, who started treatment before or after the introduction of thalidomide. The median OS in patients who started treatment after the introduction of novel agents increased by 12 months (48 vs 36 months, P<0.001). This improvement was more pronounced in patients ⩽70 years (from 39 to 74 months, P<0.001), but less evident in patients >70 years (from 26 to 33 months, P=0.27). In patients treated after the introduction of novel agents, the international staging system (ISS) could discriminate three groups with significantly different outcomes (5-year survival for ISS stage I, II and III was 66, 45 and 18%, respectively, P<0.001). ISS was also valid in patients who actually received upfront treatment with novel drugs (4-year survival rate was 85, 61 and 26% for ISS stage I, II and III patients, P=0.001).

Primary extranodal lymphomas of stomach: clinical presentation, diagnostic pitfalls and management

Gastrointestinal lymphoma is the most common form of extranodal lymphoma, accounting for 30%-40% of cases. The most commonly involved site is the stomach (60%-75% of cases), followed by the small bowel, ileum, cecum, colon and rectum. The most common histological subtypes are diffuse large B-cell lymphoma (DLBCL) and marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT). Helicobacter pylori infection has been implicated in the pathogenesis of MALT gastric lymphoma, but its role in gastric diffuse large B-cell non-Hodgkins lymphoma (NHL) is controversial. The therapeutic approach for patients with gastric NHL has been revised over the last 10 years. Conservative treatment with anthracycline-based chemotherapy alone or in combination with involved-field radiotherapy has replaced gastrectomy as standard therapy in cases with DLBCL. Additionally, MALT lymphomas are mainly treated with antibiotics alone, which can induce lasting remissions in those cases associated with H. pylori infection. Nevertheless, various therapeutic aspects for primary gastric lymphomas are still controversial and several questions remain unanswered. Among others, the role of rituximab, consolidation radiotherapy as well as H. pylori eradication in histological aggressive subtypes warrants better clarification.

Primary gastrointestinal non-Hodgkin's lymphoma: A clinicopathologic study of 128 cases in Greece. A Hellenic Cooperative Oncology Group study (HeCOG)

The aim of this retrospective study was to illustrate the clinicopathologic data and the treatment results in patients with primary gastrointestinal tract non-Hodgkins lymphoma (GI NHL). Among 810 patients with NHL, 128 cases (15.8%) were diagnosed as primary GI tract NHL. There were 79 males and 49 females with median age of 62 years. The most common primary site was the stomach (68%). Overall, 67.2% of the patients were in stages I – II, and 32.8% in stages III – IV. Simultaneous involvement of the GI tract and other extranodal sites was observed in 26 patients (20%). Extranodal marginal zone B-cell lymphoma (MZBL) (i.e., low-grade lymphoma of mucosa-associated lymphoid tissue type) accounted for 48.4% of lymphomas. Aggressive lymphomas (diffuse large B-cell lymphoma [DLBL]) accounted for 44.5%. Eighty-three patients (67.5%) achieved complete response (CR), either by surgery (43/43 patients, 17 with DLBL and 25 with MZBL) or by primary chemotherapy (40/64 patients, 22 with DLBL and 17 with MZBL). Sixty-two patients remain in CR; 33/43 after surgical resection (13/17 with DLBL and 20/25 patients with MZBL), and 29/40 after only chemotherapy (18/22 with DLBL and 10/17 with MZBL). The major prognostic factor for outcome in the present study was the stage of the disease. Patients with localized lymphoma (stage I and II) had significantly longer DFS and OS (DFS and OS at 3-year: 83% and 87%, respectively) than patients with extended disease (stage III and IV) (DFS and OS at 3-year: 46% and 60%, respectively) (P < 0.0001). The International Prognostic Index (IPI) for patients with aggressive lymphomas was prognostic only for DFS (79% for low-risk patients [IPI score 0 – 1] vs 49% for higher risk groups [IPI score >1] at 3-year, P = 0.0131).

High serum lactate dehydrogenase adds prognostic value to the international myeloma staging system even in the era of novel agents

Objectives:  High serum lactate dehydrogenase (LDH) is associated with features of advanced disease and inferior survival in multiple myeloma. It is however unclear whether LDH adds to the prognostic value of International Staging System (ISS) and whether it retains its prognostic significance in patients who are exposed to novel agent‐based therapies.

Phosphatidylinositol 3′-Kinase Catalytic Subunit α Gene Amplification Contributes to the Pathogenesis of Mantle Cell Lymphoma

Purpose: Activation of phosphatidylinositol 3′-kinase pathway is implicated in the pathogenesis of mantle cell lymphoma (MCL). The genetic change in phosphatidylinositol 3′-kinase catalytic subunit α (PIK3CA) in MCL has not been identified. Experimental Design: Thirty-five primary MCL cases and 2 MCL cell lines (GRANTA-519 and Rec-1) were used to investigate somatic mutation and gene copy number of PIK3CA. Gene copy number was determined using quantitative real-time PCR and fluorescence in situ hybridization. We used quantitative real-time reverse transcription-PCR to measure PIK3CA transcription levels. Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) and phoshorylated AKT protein levels were analyzed using Western blotting and immunohistochemistry. Flow cytometry was used to assess apoptosis after treatment of MCL cell lines and one control cell line with LY294002, a specific inhibitor of PI3KCA. Results: Fifteen of 22 (68%) MCL cases and the MCL cell lines harbored a gain (≥3) of PIK3CA gene copy number. In addition, cases with increased PIK3CA gene copy number had elevated PIK3CA mRNA levels. Furthermore, amplification of PIK3CA correlated with the status of AKT phosphorylation in 7 of 12 (58%) primary MCL cases. Inhibition of PIK3CA induced increased apoptosis in the MCL cell lines. PTEN protein expression was present in all 14 primary MCL cases and cell lines by Western blotting, whereas 5 of 33 (15%) cases tested by immunohistochemistry had loss of PTEN expression. Conclusions: We conclude that a gain of gene copy number of PIK3CA is frequent genetic alteration that contributes to MCL progression. PIK3CA is a promising therapeutic target in MCL. (Clin Cancer Res 2009;15(18):5724–32)

Prognostic significance of HER3 and HER4 protein expression in colorectal adenocarcinomas

BackgroundColorectal cancer remains a major cause of cancer mortality in the Western world. A limited number of studies has been conducted in respect of Her-3 and Her-4 expression and their correlation with clinical parameters and prognosis in colorectal carcinomas . In this study we sought to determine the pattern and the prognostic significance of HER-3 and HER-4 in colorectal adenocarcinoma.MethodsWe studied HER-3 and HER-4 protein expression in106 paraffin embedded specimens of primary colorectal tumors using immunohistochemistry. The pattern and protein expression levels of HER-3 and HER-4 were correlated with several clinical and pathological parameters.ResultsHER-3 staining displayed membranous and cytoplasmic expression pattern in 18 (17%) and 30 samples (28,3%), respectively. HER-4 membranous and cytoplasmic expression was found in 20 (18,9%) and 32 samples (30,2%), respectively. Specimens regarded as positive for HER-3 cytoplasmic expression were associated with moderate tumor grade (p = 0,032) and older median age (p = 0,010). Specimens regarded as positive for HER-4 membranous protein expression were associated with involved lymphnodes (p = 0,0003). Similar results were obtained when considering Her-3 and Her-4 protein expression irrespective of their cellular localization. There was no correlation between the expression of HER-3 and HER-4 and patients outcome.ConclusionHER-4 membranous protein expression was found to predict for lymph nodes positivity in this cohort of patients with colorectal cancer.HER-4 expression status may identify tumors with aggressive biological behavior and increased metastatic potential.

Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS): treatment outcome, relapses, prognostic factors. A single-center experience of 48 cases.

Abstract The thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS) is a rare disorder characterized by microangiopathic hemolysis and thrombocytopenia. We have undertaken a retrospective analysis of the clinical characteristics, treatment outcome, and prognosis of 48 patients diagnosed and treated in our institution during a 13-year period. Among our patients 22 (46%) had fever, 35 (73%) neurological abnormalities, and 22 (46%) renal impairment at presentation of the syndrome. All patients were treated with a multimodality regimen including plasma exchange, steroids, antiplatelet agents, and IgG infusion. Of the 48 patients, 41 achieved complete remission, two had a partial response, and five had no response and died of progressive disease. Within a median follow-up period of 40 months, ten of the 41 patients who had achieved remission relapsed, most of them within the first 2 years, and nine of these responded promptly to plasma exchange therapy. Eight deaths were observed, seven of refractory disease and one in fourth relapse. The analysis of prognostic factors revealed advanced age and severe renal impairment (creatinine levels above 2 mg%) as the only parameters associated with treatment failure and poor outcome. However, none of the pretreatment characteristics proved to be of prognostic value regarding the probability of relapse. In conclusion, TTP/HUS represent a syndrome of variable clinical expression and aggressiveness. The use of a multimodality regimen in our series produced a high response rate. Nevertheless, the early identification, based on clinical characteristics, of poor-prognosis cases that probably need more or alternative forms of treatment is an issue that remains to be elucidated in prospective trials.

XELIRI-bevacizumab versus FOLFIRI-bevacizumab as first-line treatment in patients with metastatic colorectal cancer: a Hellenic Cooperative Oncology Group phase III trial with collateral biomarker analysis

BackgroundThe aim was to compare two standard chemotherapy regimens combined with bevacizumab as first-line treatment in patients with metastatic colorectal cancer.MethodsPatients previously untreated for metastatic disease were randomized in: group A (irinotecan, capecitabine, bevacizumab, every 3 weeks; XELIRI-bevacizumab) and group B (irinotecan, leucovorin, fluorouracil, bevacizumab, every 2 weeks; FOLFIRI-bevacizumab). Primary endpoint was progression-free survival (PFS). Plasma concentrations of nitric oxide, osteopontin, TGF-β1 and VEGF-A were measured at baseline and during treatment.ResultsAmong 285 eligible patients, 143 were randomized to group A and 142 to group B. Fifty-five patients (38.5%) in group A and 57 (40.1%) in group B responded (p = 0.81). After a median follow-up of 42 months, median PFS was 10.2 and 10.8 months (p = 0.74), while median OS was 20.0 and 25.3 months (p = 0.099), for groups A and B, respectively. Most frequent grade 3–4 toxicities (group A vs group B) were neutropenia (13% vs 22%, p = 0.053) and diarrhea (19% vs 11%, p = 0.082). Baseline plasma osteopontin concentrations demonstrated prognostic significance for both PFS and OS.ConclusionsThis trial did not show significant differences in efficacy between the groups. However, the toxicity profile was different. Baseline plasma osteopontin concentrations demonstrated independent prognostic significance. (Registration number: ACTRN12610000270011)

Gemcitabine Combined with Gefitinib in Patients with Inoperable or Metastatic Pancreatic Cancer: A Phase II Study of the Hellenic Cooperative Oncology Group with Biomarker Evaluation

The combination of gemcitabine and gefitinib was evaluated in advanced pancreatic cancer. Totally, 53 patients were treated with a 7 week cycle of gemcitabine (1,000 mg/m2 given weekly) followed by six 4 week cycles of gemcitabine given on days 1, 8 and 15. Gefitinib 250 mg was administered daily. Responses were seen in 6, and stabilization of the disease in 12 patients. The main toxicity was myelotoxicity (92%). The 6-month progression-free survival (PFS) was 30%. Median PFS was 4.1 months and median survival 7.3 months with a 1 year survival rate of 27%. The above combination demonstrated promising activity in advanced pancreatic cancer.