Giuseppina Rossi

Microsatellite Instability and Colorectal Cancer Prognosis

Purpose: Many studies have evaluated the role of high levels of microsatellite instability (MSI) as a prognostic marker and predictor of the response to chemotherapy in colorectal cancer (CRC); however, the results are not conclusive. The aim of this study was to analyze the prognostic significance of high levels of MSI (MSI-H) in CRC patients in relation to fluorouracil-based chemotherapy. Experimental Design: In three different institutions, 1,263 patients with CRC were tested for the presence of MSI, and CRC-specific survival was then analyzed in relation to MSI status, chemotherapy, and other clinical and pathologic variables. Results: Two hundred and fifty-six tumors were MSI-H (20.3%): these were more frequently at a less advanced stage, right-sided, poorly differentiated, with mucinous phenotype, and expansive growth pattern than microsatellite stable carcinomas. Univariate and multivariate analyses of 5-year–specific survival revealed stage, tumor location, grade of differentiation, MSI, gender, and age as significant prognostic factors. The prognostic advantage of MSI tumors was particularly evident in stages II and III in which chemotherapy did not significantly affect the survival of MSI-H patients. Finally, we analyzed survival in MSI-H patients in relation to the presence of mismatch repair gene mutations. MSI-H patients with hereditary non–polyposis colorectal cancer showed a better prognosis as compared with sporadic MSI-H; however, in multivariate analysis, this difference disappeared. Conclusions: The type of genomic instability could influence the prognosis of CRC, in particular in stages II and III. Fluorouracil-based chemotherapy does not seem to improve survival among MSI-H patients. The survival benefit for patients with hereditary non–polyposis colorectal cancer is mainly determined by younger age and less advanced stage as compared with sporadic MSI-H counterpart.

Identification of Muir-Torre Syndrome among Patients with Sebaceous Tumors and Keratoacanthomas Role of Clinical Features, Microsatellite Instability, and Immunohistochemistry

The Muir–Torre syndrome (MTS) is an autosomal‐dominant genodermatosis characterized by the presence of sebaceous gland tumors, with or without keratoacanthomas, associated with visceral malignancies. A subset of patients with MTS is considered a variant of the hereditary nonpolyposis colorectal carcinoma, which is caused by mutations in mismatch‐repair genes. The objective of the current study was to evaluate whether a combined clinical, immunohistochemical, and biomolecular approach could be useful for the identification of Muir–Torre syndrome among patients with a diagnosis of sebaceous tumors and keratoacanthomas.

Molecular Screening for Hereditary Nonpolyposis Colorectal Cancer: A Prospective, Population-Based Study

PURPOSE Germline mutations in mismatch repair genes predispose to hereditary nonpolyposis colorectal cancer (HNPCC). To address effective screening programs, the true incidence of the disease must be known. Previous clinical investigations reported estimates ranging between 0.5% and 13% of all the colorectal cancer (CRC) cases, whereas biomolecular studies in Finland found an incidence of 2% to 2.7% of mutation carriers for the disease. The aim of the present report is to establish the frequency of the disease in a high-incidence area for colon cancer. PATIENTS AND METHODS Through the data of the local CRC registry, we prospectively collected all cases of CRC from January 1, 1996, through December 31, 1997 (N = 391). Three hundred thirty-six CRC cases (85.9% of the incident cases) were screened for microsatellite instability (MSI) with six to 12 mono- and dinucleotide markers. MSI cases were subjected to MSH2 and MLH1 germline mutation analysis and immunohistochemistry; the methylation of the promoter region was studied for MLH1. RESULTS Twenty-eight cases (8.3% of the total) showed MSI. MSI cases differed significantly from microsatellite-stable (MSS) cases for their proximal location (P <.01), high mucinous component (P <.01), and poor differentiation (P =.002). Of MSI cases studied (n = 12), only one with a family history compatible with HNPCC had a germline mutation (in MSH2). Five other patients with a family history of HNPCC (two with MSI and three with MSS tumors) did not show germline mutations. CONCLUSION We conclude that the incidence of molecularly confirmed HNPCC (one [0.3%] of 336) in a high-incidence area for CRC is lower than in previous biomolecular and clinical estimates.

Microsatellite instability in multiple colorectal tumors.

Tumor multiplicity is a hallmark of hereditary cancers: in the colon‐rectum multiple tumors represent 5–10% of all colorectal cancer cases. A portion of these cases belongs to hereditary non‐polyposis colorectal cancer (HNPCC), a genetic cancer syndrome due to mismatch repair (MMR) gene mutations, phenotypically expressed as microsatellite instability (MSI); the majority of multiple tumors, however, is apparently without any family history. We analyzed 78 (38 synchronous and 40 metachronous) neoplasms from 37 patients with multiple tumors of the large bowel, both HNPCC and sporadic, with the aim of identifying a common genetic basis in multiple tumors. DNA was extracted from normal and cancerous formalin‐fixed tissue and was analyzed for MSI using 6 markers. Tumors showing MSI in at least 2 of 6 microsatellite loci were defined as MSI(+). The overall number of MSI(+) tumors was 22 (28.2% of the total). A significant difference in the rate of MSI(+) between HNPCC and sporadic tumors was observed (85% vs. 17%). In the same patients, the MSI phenotype of synchronous tumors (both HNPCC and sporadic) tended to be more concordant than that of the metachronous ones. The higher frequency of MSI in HNPCC than in sporadic tumors, even when multiple, suggests that the involvement of MMR genes in the pathogenesis of the sporadic cases may be uncommon, thus confirming that screening for MSI in multiple colorectal tumors could be a useful tool in the identification of HNPCC in the general population. Int. J. Cancer 81:1–5, 1999.

Efficacy of standard rehabilitation in COPD outpatients with comorbidities.

A prospective study was performed to confirm the prevalence pattern of the most frequent co-morbidities and to evaluate whether characteristics of patients, specific comorbidities and increasing number of comorbidities are independently associated with poorer outcomes in a population with complex chronic obstructive pulmonary disease (COPD) submitted for pulmonary rehabilitation (PR). 316 outpatients (mean±sd age 68±7 yrs) were studied. The outcomes recorded were comorbidities and proportion of patients with a pre-defined minimally significant change in exercise tolerance (6-min walk distance (6MWD) +54 m), breathlessness (Medical Research Council (MRC) score -1 point) and quality of life (St George’s Respiratory Questionnaire -4 points). 62% of patients reported comorbidities; systemic hypertension (35%), dyslipidaemia (13%), diabetes (12%) and coronary disease (11%) were the most frequent. Of these patients, >45% improved over the minimum clinically important difference in all the outcomes. In a logistic regression model, baseline 6MWD (OR 0.99, 95% CI 0.98–0.99; p = 0.001), MRC score (OR 12.88, 95% CI 6.89–24.00; p = 0.001) and arterial carbon dioxide tension (OR 1.08, 95% CI 1.00–1.15; p = 0.034) correlated with the proportion of patients who improved 6MWD and MRC, respectively. Presence of osteoporosis reduced the success rate in 6MWD (OR 0.28, 95% CI 0.11–0.70; p = 0.006). A substantial prevalence of comorbidities in COPD outpatients referred for PR was confirmed. Only the individuals disability and the presence of osteoporosis were independently associated with poorer rehabilitation outcomes.

Hereditary colorectal cancer in the general population: from cancer registration to molecular diagnosis

BACKGROUND Hereditary non-polyposis colorectal cancer (HNPCC) is one of the most common inherited disorders predisposing to cancer. The genes responsible for the disease have recently been cloned and characterised; their mutations induce a generalised genomic instability which is particularly evident at microsatellite loci (replication error (RER)+ phenotype). AIMS To investigate how to select individuals and families in the general population who should be screened for constitutional mutations predisposing to colorectal cancer. PATIENTS/METHODS Between 1984 and 1995, 1899 colorectal malignancies in 1831 patients were registered, and in 1721 of these (94%), family trees could be obtained. Patients and families were classified into five categories according to a more or less likely genetic basis: HNPCC; “suspected” HNPCC; juvenile cases; aspecific cancer aggregation; sporadic cases. In 18 families with HNPCC as well as in 18 with suspected HNPCC, microsatellite instability in tumour tissues and constitutional mutations of two DNA mismatch repair genes (MSH2 and MLH1) could be evaluated. RER status was studied with five markers (BAT40, D2S123,D18S57, D17S787, and BAT26) in paraffin embedded tissues. Germline mutations of MSH2 orMLH1 genes were assessed on DNA and RNA extracted from lymphomonocytic cells, using reverse transcription polymerase chain reaction, single strand conformation polymorphism analysis, and direct DNA sequencing. RESULTS HNPCC represented 2.6% and suspected HNPCC 4.6% of all registered colorectal neoplasms. Eleven out of 18 HNPCC families (61%) showed microsatellite instability as opposed to four (of 18) suspected HNPCC (22%; p<0.02). Three germline mutations (two inMSH2 and one inMLH1 gene) were found in three different large HNPCC families, whereas no mutations were detected in suspected HNPCC. CONCLUSIONS In this study of cancer genetic epidemiology, data from a tumour registry were analysed and this ultimately led to the identification and selection of families that should be tested for mutator gene mutations. With the use of a population based approach, the incidence of mutations was appreciably lower than previously reported and limited to families with full blown HNPCC. It is possible that in most families with a clinical spectrum of HNPCC (or suspected HNPCC) other DNA mismatch repair genes are involved in the pathogenesis of the disease.

Myeloperoxidase-Positive Cell Infiltration in Colorectal Carcinogenesis as Indicator of Colorectal Cancer Risk

Colorectal mucosa is targeted by toxic agents, which can initiate or promote colon cancer. The mechanism of damage might be a focal irritation with loss of normal epithelial cell barrier function. Genetic alterations in tumors may also affect host inflammatory response. The aim of this study was to define the extent of inflammation in colorectal mucosa, along colorectal carcinogenesis, and in microsatellite stable and unstable colorectal carcinomas. We collected 103 samples of normal colorectal mucosa from 65 patients (35 with colorectal cancer or adenoma, 8 with inflammatory bowel diseases, and 22 controls with normal colonoscopy). We also examined 24 aberrant crypt foci, 14 hyperplastic polyps, 16 adenomas, and 67 samples of colorectal carcinoma. Immunohistochemistry was used to count myeloperoxidase (MPO)-positive cells (neutrophils and monocytes) in ×100 optical fields under a light microscope. Patients with colorectal tumors had a higher mean number of MPO-positive cells in normal mucosa than controls (mean ± SD, 2.7 ± 2.0 versus 1.4 ± 1.4; P = 0.017). MPO-positive cell number was tightly linked to dysplasia in aberrant crypt foci and adenomas, and it was higher in carcinomas microsatellite unstable than those microsatellite stable (21.6 ± 15.5 versus 11.9 ± 8.0; P < 0.01). MPO immunohistochemistry is a simple and reliable technique for the quantification of inflammation in colorectal mucosa., and it may be a potential marker of colorectal cancer risk. Microsatellite instability seems to influence host immune responses to colorectal carcinoma. These observations strongly support a key role of inflammation in colorectal carcinogenesis. (Cancer Epidemiol Biomarkers Prev 2008;17(9):2291–7)

Molecular genetic alterations and clinical features in early-onset colorectal carcinomas and their role for the recognition of hereditary cancer syndromes.

OBJECTIVES:Colorectal cancer (CRC) occurs rarely in young individuals (<45 yr) and represents one of the criteria for suspecting hereditary cancer families. In this study we evaluated clinical features and molecular pathways (chromosomal instability [CIN] and microsatellite instability [MSI]) in early-onset CRC of 71 patients.METHODS:Detailed family and personal history were obtained for each patient. Expression of APC, β-catenin, p53, MLH1, MSH2, and MSH6 genes was evaluated by immunohistochemistry. MSI analysis was performed and constitutional main mutations of the mismatch repair (MMR) genes were searched by gene sequencing.RESULTS:Fourteen (19.7%) out of the 71 cases showed both MSI and altered expression of MMR proteins. In the 57 MSI-negative (MSI−) lesions altered expression of APC, β-catenin, and p53 genes were found more frequently than in MSI-positive(MSI+) tumors. Seven (50%) out of the 14 patients with MSI+ tumors presented clinical features of Lynch syndrome (hereditary non-polyposis colorectal cancer [HNPCC]) and in all but one, constitutional mutations in MLH1 or MSH2 genes could be detected. The same mutations were also found in other family members.CONCLUSIONS:Our study demostrates the involvement of CIN in a majority of early-onset colorectal tumors. Furthermore, we identified Lynch syndromes in seven cases (50%) of early-onset colorectal carcinomas with impairment of the MMR system. These results suggest that patients with early-onset CRC should be screened for hereditary cancer syndrome through clinical and molecular characterizations.

Long-term outcome of chronic myeloid leukemia patients treated frontline with imatinib

For almost 10 years imatinib has been the therapeutic standard of chronic myeloid leukemia. The introduction of other tyrosine kinase inhibitors (TKIs) raised a debate on treatment optimization. The debate is still heated: some studies have protocol restrictions or limited follow-up; in other studies, some relevant data are missing. The aim of this report is to provide a comprehensive, long-term, intention-to-treat, analysis of 559 newly diagnosed, chronic-phase, patients treated frontline with imatinib. With a minimum follow-up of 66 months, 65% of patients were still on imatinib, 19% were on alternative treatment, 12% died and 4% were lost to follow-up. The prognostic value of BCR-ABL1 ratio at 3 months (⩽10% in 81% of patients) was confirmed. The prognostic value of complete cytogenetic response and major molecular response at 1 year was confirmed. The 6-year overall survival was 89%, but as 50% of deaths occurred in remission, the 6-year cumulative incidence of leukemia-related death was 5%. The long-term outcome of first-line imatinib was excellent, also because of second-line treatment with other TKIs, but all responses and outcomes were inferior in high-risk patients, suggesting that to optimize treatment results, a specific risk-adapted treatment is needed for such patients.

Effects of early inpatient rehabilitation after acute exacerbation of COPD

We have undertaken an observational retrospective cohort study to assess feasibility and clinical effectiveness of early rehabilitation in patients recovering from acute exacerbation of COPD (AECOPD). A cohort of 1826 inpatients (73% male, age 70+/-8 yrs, FEV(1) 50+/-16% pred.) admitted to a pulmonary rehabilitation (PR) program and completing at least 15 sessions were divided into categories according to their dyspnoea grade (Medical Research Council--MRC scores 2-5) as assessed before AECOPD. The pre-post changes in 6-minute walking distance (6MWD) test, perceived end-effort dyspnoea (Borg scale), and self-reported quality of life (St. Georges respiratory Questionnaire: SGRQ) were measured throughout. Absolute change in 6MWD (52 [95%CI 45-59], 65 [95%CI 60-70], 63 [95%CI 59-66], and 70 [95%CI 67-74] meters in MRC 2-5 respectively) and the percentage of patients achieving the minimal clinically important difference (MCID) of +54 m (40, 55, 57, and 61%, respectively, p=0.001) differed across MRC grades. Proportion of patients able to reach > or = 350 m at the 6MWD after PR was higher in MRC 4 and 5 (18 and 22%) as compared to MRC 2 and 3 (6 and 15%). Early PR in a cohort of AECOPD patients is feasible and it is associated to clinically meaningful improvement in exercise tolerance independent on the severity of dyspnoea. The proportion of patients reaching the limit of > or = 350 m after this intervention is higher in the most severe patients.