Ángel Segura

New insights into POLE and POLD1 germline mutations in familial colorectal cancer and polyposis

Germline mutations in DNA polymerase ɛ (POLE) and δ (POLD1) have been recently identified in families with multiple colorectal adenomas and colorectal cancer (CRC). All reported cases carried POLE c.1270C>G (p.Leu424Val) or POLD1 c.1433G>A (p.Ser478Asn) mutations. Due to the scarcity of cases reported so far, an accurate clinical phenotype has not been defined. We aimed to assess the prevalence of these recurrent mutations in unexplained familial and early-onset CRC and polyposis, and to add additional information to define the clinical characteristics of mutated cases. A total of 858 familial/early onset CRC and polyposis patients were studied: 581 familial and early-onset CRC cases without mismatch repair (MMR) deficiency, 86 cases with MMR deficiency and 191 polyposis cases. Mutation screening was performed by KASPar genotyping assays and/or Sanger sequencing of the involved exons. POLE p.L424V was identified in a 28-year-old polyposis and CRC patient, as a de novo mutation. None of the 858 cases studied carried POLD1 p.S478N. A new mutation, POLD1 c.1421T>C (p.Leu474Pro), was identified in a mismatch repair proficient Amsterdam II family. Its pathogenicity was supported by cosegregation in the family, in silico predictions, and previously published yeast assays. POLE and POLD1 mutations explain a fraction of familial CRC and polyposis. Sequencing the proofreading domains of POLE and POLD1 should be considered in routine genetic diagnostics. Until additional evidence is gathered, POLE and POLD1 genetic testing should not be restricted to polyposis cases, and the presence of de novo mutations, considered.

EPCAM Germ Line Deletions as Causes of Lynch Syndrome in Spanish Patients

The standard genetic test for Lynch syndrome (LS) frequently reveals an absence of pathogenic mutations in DNA mismatch repair genes known to be associated with LS. It was recently shown that germ line deletions in the last exons of EPCAM are involved in the etiology of LS. The aim of this study was to evaluate the prevalence of EPCAM deletions in a Spanish population and the clinical implications of deletion. Probands from 501 families suspected of having LS were enrolled in the study. Twenty-five cases with MSH2 loss were identified: 10 had mutations of MSH2, five had mutations of MSH6, and 10 did not show MSH2/MSH6 mutations. These 25 cases were analyzed for EPCAM deletions using multiplex ligation-dependent probe amplification, and deletions were mapped using long-range PCR analysis. One subject with no MSH2/MSH6 mutations had a large deletion in the EPCAM locus that extended for 8.7 kb and included exons 8 and 9. The tumor exhibited MSH2 promoter hypermethylation. EPCAM deletion analysis followed by MSH2 methylation testing of the tumor is a fast low-cost procedure that can be used to identify mutations that cause LS. We propose that this procedure be incorporated into clinical genetic analysis strategies and present a decision-support flow diagram for the diagnosis of LS.

Primary Lymphoma of Bone: A Clinico-Pathological Review and Analysis of Prognostic Factors

Primary non-Hodgkin’s bone lymphoma (PBL) is an uncommon malignancy first described by Oberling in 1928 [1], and established as a different clinical entity in 1939 [2]. It represents 7% of all bone tumors and less than 5% of non-Hodgkin’s extranodal lymphomas [3]. A retrospective review was performed with all consecutive patients with PBL diagnosed and treated at our center between January 1975 and December 2000. All patients had histological confirmation of non-Hodgkin’s lymphoma and were classified according to the Working Formulation. Tumor burden was evaluated with the M.D. Anderson criteria. Staging was based on the Ann Arbor classification. Assessment of response was performed according to the WHO criteria. Survival curves were estimated with the Kaplan –Meier method, and compared by means of the log-rank test. The Cox’s proportional hazard model was used to identify independent prognostic factors of survival. Age, stage, extranodal involved areas, performance status, and serum LDH levels, included in the International Prognostic Index (IPI) [4] were analyzed together. Patient characteristics are shown in Table I. All patients received treatment for PBL with either chemotherapy (1 patient, 5%), radiotherapy (3 patients, 14%), or combined chemotherapy+radiotherapy (17 cases, 81%). Chemotherapy schedules included anthracyclines in 83% cases. The most frequent employed of them was CHOP. The median dose of radiotherapy delivered was 40 Gy, with a boost of 500 cGy on primary lesions. Patients with PBL treated with chemotherapy received a median of 6 cycles (range, 1 – 12). Sixteen patients achieved a complete response (76%), 1 showed a disease stabilization (5%), and 4 patients progressed (19%). Six patients had a recurrence of the disease (29%), 2 of them primarily treated with radiotherapy alone, 1 case treated with chemotherapy alone, and 3 patients treated with combined modality. At the time of data analysis, with a median follow-up of 87 months (range, 7 – 297), 12 patients (57%) are alive and disease-free, while 9 have died, in 6 cases due to progression of non-Hodgkin’s lymphoma (29%) and in 3 due to other causes (radiation-induced osteosarcoma,

Clinical predictors of severe toxicity in patients treated with combination chemotherapy with irinotecan and/or oxaliplatin for metastatic colorectal cancer: a single center experience.

IntroductionLittle has been published regarding clinical predictors of severe toxicity in patients with metastatic colorectal cancer (CRC) treated with combination chemotherapy (CT) with oxaliplatin and/or irinotecan.Material and MethodsWe analyzed retrospectively 142 patients treated between 1996 and 2004 in our center with these regimes with regards to grade 3–4 toxicity and overall survival (OS) rates. Köhnes prognostic classification could be applied in all patients.ResultsKöhne classification: good (54.2%), intermediate (26.8%), and poor prognosis (19%). 50.4% received irinotecan-based CT. Median number of cycles 6 with a total response rate of 38.9%. 23.2% stopped first-line CT due to toxicity. 50.7% suffered grade 3–4 toxicity: digestive (28.2%), hematologic (19.7%), and fatigue (25.4%). 7.7% episodes of neutropenic fever with 4.9% toxic deaths. 70.9% of grade 3–4 episodes occurred in the first four cycles. Median follow-up of 33.9 mo; median OS of 15.9 mo. For Köhne classification: good (20 mo), intermediate (15.8 mo), and poor (6.8 mo). Toxicity analysis: female sex and age>70 yr predicted higher overall grade 3–4 toxicity, with no differences in CT efficacy; age>70 yr and PS>1 predicted higher grade 3–4 fatigue. No relationship could be found between baseline laboratory characteristics and higher toxicity, except baseline hemoglobin and grade 3–4 hematologic toxicity.ConclusionsFemale and elderly patients have a higher grade 3–4 toxicity rate when treated with combination CT with oxaliplatin or irinotecan. Prognostic classifications such as Köhnes can help differentiate subgroups of patients who benefit little with the use of combination CT.

Long-term results after combined modality treatment for non-metastatic osteosarcoma

Since the introduction of multimodality treatment, the prognosis of patients with high-grade non-metastatic osteosarcoma has significantly improved. A retrospective review was performed to assess the long-term results of this approach in a single centre setting, and to investigate the impact of potential clinical prognostic factors. Between 1985 and 1993, 35 patients with stage II-A and II-B osteosarcoma underwent preoperative chemotherapy (high-dose methotrexate), wide surgery, and adjuvant chemotherapy (cisplatin-doxorubicin/bleomycin-cyclophosphamide-dactinomycin) (modified T-10A protocol). There were 19 males and 16 females. Median patient age was 17 y (range 12–42). Primary tumour sites were the extremities (83%) and axial bones (17%). In spite of an unfavourable grade 3–4 histologic response rate to high-dose methotrexate of 12%, 31 (88%) patients were able to undergo limb-sparing surgery and 28 (80%) were rendered disease free after the planned therapy. Median follow-up was 8 y. The actuarial overall survival and disease-free survival rates were 64% and 49% at 5 y, and 59% and 49% at 10y, respectively. Tumour size and primary site were significant prognostic factors for survival in univariate analyses. In conclusion, long-term survival after combined modality treatment can be achieved in more than 60% of patients with localised osteosarcoma, including non-appendicular lesions. Limb-sparing surgery is a realistic goal for most cases. The prognostic value of tumour necrosis and the efficacy of neoadjuvant chemotherapy should be interpreted according to individual high-dose methotrexate scheduling.

Management of Advanced Pancreatic Cancer with Gemcitabine Plus Erlotinib: Efficacy and Safety Results in Clinical Practice

CONTEXT The combination of gemcitabine and erlotinib is a standard first-line treatment for unresectable, locally advanced or metastatic pancreatic cancer. We reviewed our single centre experience to assess its efficacy and toxicity in clinical practice. METHODS Clinical records of patients with unresectable, locally advanced or metastatic pancreatic cancer who were treated with the combination of gemcitabine and erlotinib were reviewed. MAIN OUTCOME MEASURES Univariate survival analysis and multivariate analysis were carried out to indentify independent predictors factors of overall survival. RESULTS Our series included 55 patients. Overall disease control rate was 47%: 5% of patients presented complete response, 20% partial response and 22% stable disease. Median overall survival was 8.3 months). Cox regression analysis indicated that performance status and locally advanced versus metastatic disease were independent factors of overall survival. Patients who developed acne-like rash toxicity, related to erlotinib administration, presented a higher survival than those patients who did not develop this toxicity. CONCLUSIONS Gemcitabine plus erlotinib doublet is active in our series of patients with advanced pancreatic cancer. This study provides efficacy and safety results similar to those of the pivotal phase III clinical trial that tested the same combination.

Evidence for classification of c.1852_1853AA>GC in MLH1 as a neutral variant for Lynch syndrome

BackgroundLynch syndrome (LS) is an autosomal dominant inherited cancer syndrome characterized by early onset cancers of the colorectum, endometrium and other tumours. A significant proportion of DNA variants in LS patients are unclassified. Reports on the pathogenicity of the c.1852_1853AA>GC (p.Lys618Ala) variant of the MLH1 gene are conflicting. In this study, we provide new evidence indicating that this variant has no significant implications for LS.MethodsThe following approach was used to assess the clinical significance of the p.Lys618Ala variant: frequency in a control population, case-control comparison, co-occurrence of the p.Lys618Ala variant with a pathogenic mutation, co-segregation with the disease and microsatellite instability in tumours from carriers of the variant. We genotyped p.Lys618Ala in 1034 individuals (373 sporadic colorectal cancer [CRC] patients, 250 index subjects from families suspected of having LS [revised Bethesda guidelines] and 411 controls). Three well-characterized LS families that fulfilled the Amsterdam II Criteria and consisted of members with the p.Lys618Ala variant were included to assess co-occurrence and co-segregation. A subset of colorectal tumour DNA samples from 17 patients carrying the p.Lys618Ala variant was screened for microsatellite instability using five mononucleotide markers.ResultsTwenty-seven individuals were heterozygous for the p.Lys618Ala variant; nine had sporadic CRC (2.41%), seven were suspected of having hereditary CRC (2.8%) and 11 were controls (2.68%). There were no significant associations in the case-control and case-case studies. The p.Lys618Ala variant was co-existent with pathogenic mutations in two unrelated LS families. In one family, the allele distribution of the pathogenic and unclassified variant was in trans, in the other family the pathogenic variant was detected in the MSH6 gene and only the deleterious variant co-segregated with the disease in both families. Only two positive cases of microsatellite instability (2/17, 11.8%) were detected in tumours from p.Lys618Ala carriers, indicating that this variant does not play a role in functional inactivation of MLH1 in CRC patients.ConclusionsThe p.Lys618Ala variant should be considered a neutral variant for LS. These findings have implications for the clinical management of CRC probands and their relatives.

Neuroendocrine Tumor Heterogeneity Adds Uncertainty to the World Health Organization 2010 Classification: Real‐World Data from the Spanish Tumor Registry (R‐GETNE)

BACKGROUND Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are a complex family of tumors of widely variable clinical behavior. The World Health Organization (WHO) 2010 classification provided a valuable tool to stratify neuroendocrine neoplasms (NENs) in three prognostic subgroups based on the proliferation index. However, substantial heterogeneity remains within these subgroups, and simplicity sometimes entails an ambiguous and imprecise prognostic stratification. The purpose of our study was to evaluate the prognostic impact of histological differentiation within the WHO 2010 grade (G) 1/G2/G3 categories, and explore additional Ki-67 cutoff values in GEP-NENs. SUBJECTS, MATERIALS, AND METHODS A total of 2,813 patients from the Spanish National Tumor Registry (RGETNE) were analyzed. Cases were classified by histological differentiation as NETs (neuroendocrine tumors [well differentiated]) or NECs (neuroendocrine carcinomas [poorly differentiated]), and by Ki-67 index as G1 (Ki-67 <2%), G2 (Ki-67 3%-20%), or G3 (Ki-67 >20%). Patients were stratified into five cohorts: NET-G1, NET-G2, NET-G3, NEC-G2, and NEC-G3. RESULTS Five-year survival was 72%. Age, gender, tumor site, grade, differentiation, and stage were all independent prognostic factors for survival. Further subdivision of the WHO 2010 grading improved prognostic stratification, both within G2 (5-year survival: 81% [Ki-67 3%-5%], 72% [Ki-67 6%-10%], 52% [Ki-67 11%-20%]) and G3 NENs (5-year survival: 35% [Ki-67 21%-50%], 22% [Ki-67 51%-100%]). Five-year survival was significantly greater for NET-G2 versus NEC-G2 (75.5% vs. 58.2%) and NET-G3 versus NEC-G3 (43.7% vs. 25.4%). CONCLUSION Substantial clinical heterogeneity is observed within G2 and G3 GEP-NENs. The WHO 2010 classification can be improved by including the additive effect of histological differentiation and the proliferation index. IMPLICATIONS FOR PRACTICE Gastroenteropancreatic neuroendocrine neoplasms are tumors of widely variable clinical behavior, roughly stratified by the World Health Organization (WHO) 2010 classification into three subgroups based on proliferation index. Real-world data from 2,813 patients of the Spanish Registry RGETNE demonstrated substantial clinical heterogeneity within grade (G) 2 and G3 neuroendocrine neoplasms. Tumor morphology and further subdivision of grading substantially improves prognostic stratification of these patients and may help individualize therapy. This combined, additive effect shall be considered in future classifications of neuroendocrine tumors and incorporated for stratification purposes in clinical trials.

Adjuvant chemoradiation in gastric cancer: long-term outcomes and prognostic factors from a single institution

Background Adjuvant chemoradiotherapy (CRT) improves relapse-free (RFS) and overall survival (OS) in patients with resected gastric cancer. However, difficulties in standardizing an optimal surgical approach and a perceived higher toxicity compared with the perioperative approach have limited its widespread application in Europe. The aim of our study was to assess toxicity and long-term outcomes of adjuvant CRT at our institution. Methods A retrospective review (September 2001-January 2012) was completed of patients with resected gastric cancer who received adjuvant CRT (Macdonald regimen). Adverse events and completion rates, RFS and OS were estimated. Univariate and multivariate analyses of prognostic factors for OS were performed. Results Eighty-seven patients were included. Most had diffuse (52%) and locally advanced tumors (stage III-IV; 66.7%). D2 lymphadenectomy was performed in 80.5%. The most frequent grade 3-4 toxicities were gastrointestinal (28%) and stomatitis (20%), with 78.2% completing treatment. With a median follow-up of 115 months, 58.5% had relapsed, most of them distantly. Median RFS and OS were 9 and 24 months, respectively. Univariate analysis showed that performance status, stage and lymph node burden were significant factors for OS. In the multivariate study, only stage and lymph node burden remained as independent OS predictors. Conclusions Our implementation of the Macdonald regimen achieved worse outcomes than those reported in the INT-0116 trial. The rate of distant relapse remains unacceptably high. Higher rate of positive lymph nodes and of diffuse tumors could explain some differences. The use of perioperative chemotherapy, especially in patients with a poorer prognosis, might improve these results.

Characterization of a novel POLD1 missense founder mutation in a Spanish population

We identified a new and a recurrent POLD1 mutation associated with predisposition to colorectal cancer (CRC). We characterized the molecular and clinical nature of the potential POLD1 founder mutation in families from Valencia (Spain).