Frameshift mutational target gene analysis identifies similarities and differences in constitutional mismatch repair-deficiency and Lynch syndrome.

Mismatch-repair deficient (MMR-D) malignancies include Lynch Syndrome (LS), which is secondary to germline mutations in one of the MMR genes, and the rare childhood-form of constitutional mismatch repair-deficiency (CMMR-D); caused by bi-allelic MMR gene mutations. A hallmark of LS-associated cancers is microsatellite instability (MSI), characterized by coding frameshift mutations (cFSM) in target genes. By contrast, tumors arising in CMMR-D patients are thought to display a somatic mutation pattern differing from LS. This study has the main goal to identify cFSM in MSI target genes relevant in CMMR-D and to compare the spectrum of common somatic mutations, including alterations in DNA polymerases POLE and D1 between LS and CMMR-D. CMMR-D-associated tumors harbored more somatic mutations compared to LS cases, especially in the TP53 gene and in POLE and POLD1, where novel mutations were additionally identified. Strikingly, MSI in classical mononucleotide markers BAT40 and CAT25 was frequent in CMMR-D cases. MSI-target gene analysis revealed mutations in CMMR-D-associated tumors, some of them known to be frequently hit in LS, such as RNaseT2, HT001, and TGFßR2. Our results imply a general role for these cFSM as potential new drivers of MMR-D tumorigenesis.

Older patients with inoperable non-small cell lung cancer: long-term survival after concurrent chemoradiotherapy.

PURPOSE: Considering the various comorbidities associated with aging, the feasibility and usefulness of concurrent chemoradiotherapy (CRT) in older patients with inoperable non-small cell lung cancer (NSCLC) is a controversial issue. Here, we compared the feasibility of CRT and the effects of various comorbidities on the prognosis of a minimally selected population of inoperable NSCLC patients aged 60-77 years. PATIENTS AND METHODS: The study comprised 161 patients with inoperable NSCLC who received CRT with a target radiation dose greater than 60 Gy and platinum-based chemotherapy from 1998 to 2007. The total population included 69 patients aged 60-69 years and 53 aged 70-77 years. These two age cohorts were included in the study with a follow-up of a median 14.5 months. RESULTS: The two groups showed no differences in long-term survival, as reflected by the 5-year survival rates of 13.0 ± 4.1 % (60- to 69-year-olds) and 14.4 ± 4.9 % (70- to 77-year-olds). During the treatment phase, the groups were comparable in terms of toxicity and the feasibility of chemotherapy. Compared to patients in their 60s, the septuagenarians had more pulmonary comorbidities (p = 0.02), diabetes mellitus (p = 0.04), cardiac comorbidities (p = 0.08), and previous cancer disease (p = 0.08) that exerted a negative effect on survival. In patients without comorbidities, there were no differences between the age groups. CONCLUSION: Age is not a contraindication for concurrent CRT per se, because elderly patients do not have a worse long-term prognosis than younger seniors. However, "elderly patients" (≥ 70-77 years) have more concomitant diseases associated with shorter survival than "moderately aged patients" (≥ 60-69 years).

Prognostic and diagnostic implications of epithelial cell adhesion/activating molecule (EpCAM) expression in renal tumours: a retrospective clinicopathological study of 948 cases using tissue microarrays.

OBJECTIVE: To evaluate the expression and prognostic value of epithelial cell adhesion/activating molecule (EpCAM) in a large set of renal cell carcinomas (RCCs) using a tissue microarray (TMA) approach. MATERIAL AND METHODS: We studied the immunohistochemical expression and overexpression of EpCAM on TMAs containing formalin-fixed, paraffin-embedded samples of 948 patients with documented renal tumours. EpCAM expression was defined as the presence of a specific membranous staining in >5% of the tumour cells. EpCAM overexpression was specified by calculating a total staining score (score range 0-12) as the product of a proportion score and an intensity score, and defined as a score >4. RESULTS: Of 948 cases, 927 (97.8%) were evaluable morphologically (haematoxylin and eosin stain). EpCAM expression was found in 233/642 (36.3%), 126/155 (81.3%), 54/68 (78.3%), 17/45 (37.8%), 13/30 (43.3%) of clear-cell RCC, papillary RCC (pRCC), chromophobe RCC (cpRCC), oncocytomas and other unclassified tumour types, respectively. Log-rank tests showed a significantly longer overall survival (OS [P = 0.047]) and a trend of EpCAM expression to be associated with a longer progression-free survival (PFS) in all RCC entities (P = 0.065). EpCAM overexpression was significantly correlated with a better PFS in all RCC subtypes, cpRCC and pRCC (P = 0.011, 0.043 and 0.025, respectively). In multivariate analysis EpCAM overexpression was an independent marker for longer PFS in all RCC entities as well as in high grade RCC (P = 0.009 and P = 0.010, respectively). CONCLUSIONS: The histological subtypes associated with a high rate of EpCAM expression were cpRCC and pRCC. This retrospective analysis demonstrated a trend towards longer OS and PFS for all major RCC subtypes. EpCAM expression had significant prognostic value in patients with cpRCC and pRCC. Furthermore, EpCAM overexpression in high grade RCC may be a helpful marker for prognostication.

ERBB2 Amplification as a Predictive and Prognostic Biomarker in Upper Tract Urothelial Carcinoma.

Upper tract urothelial carcinomas (UTUCs) occur in about 5-10% of all urothelial carcinomas and are frequently discovered in high-stage disease. We aimed to evaluate human epidermal growth factor receptor 2 (ERBB2) protein expression immunohistochemically and ERBB2 amplification in UTUCs by fluorescence in situ hybridization, applying a tissue microarray technique. ERBB2 overexpression and ERBB2 amplification were defined according to the recommendations of the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) for breast cancer and gastric carcinoma (GC), revealing scores of 2+ and 3+ in 10.2% and 41.8% of UTUCs, respectively. The performance parameters showed obviously higher sensitivity of ERBB2 immunoscoring according to the ASCO/CAP criteria for GC. ERBB2 amplification was detected in 10.5% of UTUCs. ERBB2 overexpression was more likely to be found in high-grade tumors and was associated with tumor progression. Univariable Cox regression analysis revealed a significantly lower progression-free survival (PFS) in cases with ERBB2 immunoscores of 2+ or 3+ according to the ASCO/CAP guidelines for GC. UTUCs with ERBB2 amplification showed a significantly shorter PFS in the multivariable Cox regression analysis. Irrespective of their ERBB2 status, patients with UTUC treated with platin showed a significantly lower PFS than UTUC patients who had not received any platin-based therapy. In addition, UTUC patients with a normal ERBB2 gene status who had not received platin-based therapy showed significantly longer overall survival. The results suggest that ERBB2 is a biomarker for progression in UTUCs and may define a distinct subgroup of UTUCs. As previously shown, ERBB2 amplification is infrequent. However, the small number of patients diagnosed with ERBB2-amplified UTUC might benefit from ERBB2-targeted cancer therapy. In clinical-pathological routine diagnostics, the determination of ERBB2 amplification is an established method in some defined entities and also successful in small samples. Still, the simultaneous use of ERBB2 immunohistochemistry and ERBB2 in situ hybridization would be important in order to record the low rate of amplified UTUC cases as completely as possible.

Loss of Mismatch-repair Protein Expression and Microsatellite Instability in Upper Tract Urothelial Carcinoma and Clinicopathologic Implications.

BACKGROUND: Upper tract urothelial carcinoma (UTUC) may arise in the setting of hereditary non-polyposis colorectal cancer (Lynch syndrome [LS]) or sporadically. Variable frequencies of microsatellite instability (MSI) were found in UTUC. For advanced solid MSI tumors, targeted therapy with programmed death-ligand 1 inhibitors is available. Therefore, we aimed to determine the prevalence of mismatch repair (MMR) protein loss and MSI in UTUC using a tissue microarray approach and further molecular and correlation analysis. MATERIALS AND METHODS: We studied the immunohistochemical expression of MLH1, MSH2, MSH6, and PMS2 on tissue microarrays containing formalin-fixed, paraffin-embedded samples of 128 patients with UTUC. MSI analysis was performed in 79 cases with deficient MMR protein expression, and/or in patients aged 60 years and below, and/or other tumors possibly related to LS. RESULTS: Loss of MMR protein expression was seen in 24 (18.8%) of 128 cases. MSI analysis revealed MSI-high in 29, MSI-low in 7 cases. The Fisher exact test demonstrated significant differences between MSI and loss of MMR protein expression, clinically possible LS, tumor growth pattern, inverted growth pattern, and death (P < .001, P < .001, P = .002, P = .003, and P = .033, respectively). MSI does not appear to influence survival (overall and progression-free), but there was a significant shorter progression-free survival in MSI-high versus MSS patients who had received chemotherapy. CONCLUSION: The frequency of MSI in UTUC was 36 (28.1%) of 128 patients with a good accuracy of immunohistochemistry. In daily practice, MSI screening especially is recommended in patients with advanced UTUC and inverted papillary tumor growth pattern with the aim of screening patients for possible targeted therapy.

Differences between clinical trial participants and patients in a population-based registry: the German Rectal Cancer Study vs. the Rostock Cancer Registry.

PURPOSE: There are few data on whether the samples of randomized phase III studies are representative for cancer patients in general populations. METHODS: We compared patient and disease characteristics of patients with stage II or III rectal cancer from the German Rectal Cancer Study (657 patients, 1995-2002) or the Rostock Cancer Registry (371 patients, 1997-2003). Differences between the Study and the Registry were analyzed for subgroups who received neoadjuvant chemoradiotherapy before resection or primary resection with or without postoperative chemoradiotherapy. RESULTS: Study and Registry patients differed in age (median, 61.7 vs. 65.0 years, P < 0.001) and proportion of women (31.3 percent vs. 38.4 percent, P < 0.004). Significant age and gender differences were seen in primary resection but not in neoadjuvant subgroups. In neoadjuvant and in primary resection subgroups, Study participants were more likely than Registry patients to have tumor location in the lower third of the rectum, a higher rate of R0 resection, a greater number of lymph nodes assessed, and fewer T4 tumors. In the primary resection subgroups, Study participants were more likely to have received postoperative chemoradiotherapy. Multivariate analyses showed no effect of population type (Study vs. Registry) on disease-free or overall survival in neoadjuvant subgroups, but increased risk for Registry patients in primary resection subgroups. CONCLUSIONS: Participants in clinical trials such as the German Rectal Cancer Study are not representative of all cancer patients of a general population. To enable wider extrapolation of results, future studies should include elderly and high-risk patients.

Frequent and Yet Unreported GNAQ and GNA11 Mutations are Found in Uveal Melanomas.

Malignant melanoma of the uvea is the most common primary malignant tumor in the eye. We aimed to analyze GNAQ and GNA11 mutations in uveal melanomas using formalin-fixed, paraffin-embedded material and correlate the results with clinicopathological parameters. Tumor tissue was microdissected followed by amplification of GNAQ exon 4 and 5, GNA11 exon 4 and 5, and finally analyzed by Sanger sequencing. A total of 64.4 GNA11/GNAQ mutations, including ten yet unreported, were found. Two cases showed multiple mutations. Overall survival was significantly shorter in the uveal melanoma cohort with GNAQ exon 5 mutation. In concordance with previous studies, high frequencies of mutations in GNAQ or GNA11 were detected. Interestingly, in about 20% of UM, not yet reported mutations in GNAQ or GNA11 were seen. Rarely, uveal melanoma may harbor double mutations in GNAQ and/or GNA11. Recent data imply, that implementation of GNAQ/GNA11 mutation analysis in routine diagnostic procedures might be helpful for future therapeutic decisions.

Expression and clinicopathological correlations of retinoid acid receptor responder protein 1 in renal cell carcinomas.

AIM: To evaluate the expression and prognostic value of RARRES1 at protein level in renal cell carcinoma (RCC). MATERIALS & METHODS: Expression profile of RARRES1 was analyzed in 903 documented RCC followed by clinicopathological correlations and survival analysis. RESULTS: RARRES1 expression was seen in 72.5% of RCC. A stronger RARRES1 expression was seen in high grade compared with low grade RCC (p < 0.001). Logrank tests revealed shorter overall survival in RARRES1 positive RCC (p = 0.006) and in pT1/2 tumors with RARRES1 expression (p = 0.002). CONCLUSION: The variable expression profile in low and high grade RCC may reflect and confirm the differences of previous gene expression analysis. There was a significant prognostic value of RARRES1 expression in patients with RCC, especially in pT1/2 tumors.

C-kit overexpression is not associated with KIT gene mutations in chromophobe renal cell carcinoma or renal oncocytoma.

INTRODUCTION: C-kit overexpression has previously been described in chromophobe renal cell carcinoma (cpRCC) and renal oncocytoma (RO). However, so far no KIT mutations have been found. The objective of our study was to analyse c-kit in a large cohort of renal tumors and to perform KIT mutation analysis in a subset cpRCC and RO cases with overexpression of c-kit. MATERIALS AND METHODS: We studied the immunohistochemical expression of c-kit on tissue microarrays containing formalin-fixed, paraffin-embedded samples of 948 patients with renal tumors. CpRCC and RO cases with c-kit overexpression (n=23) were analyzed for KIT mutations in exons 9, 11, 13, 14, 15, and 17. RESULTS: Expression of c-kit was found in 6/642 (0.9%) clear cell RCC, 3/154 (1.9%) papillary RCC, 54/69 (78.3%) cpRCC, 37/45 (82.2%) RO and 2/30 (6.7%) of other unclassified tumor types. In none of the RO and cpRCC cases analyzed, a KIT gene mutation was found. CONCLUSION: C-kit expression is found in the majority of cpRCC and RO, but these tumors do not harbor the usual c-kit activating mutations. This may have implications for the use of tyrosine kinase inhibitors in patients with advanced cpRCC and c-kit expression.

Incidence, therapy and prognosis of colorectal cancer in different age groups. A population-based cohort study of the Rostock Cancer Registry.

PURPOSE: Determination of frequency, treatment modalities used and prognoses of colorectal cancer in a population-specific analysis in relation to age. MATERIAL AND METHODS: In 1999 and 2000, 644/6,016 patients were documented as having colorectal carcinomas in the Cancer Registry of Rostock. 39 patients were excluded (16 cases: "in situ" carcinomas; 23 cases: insufficient data). Three age groups were formed: < 60 years, 60-74 years; > or = 75 years. RESULTS: The relative percentage of colorectal cancer increases with advanced age (< 60 years 7%; 60-74 years 12%, > or = 75 years 15%; p < 0.001). In older patients with stage III carcinomas, adjuvant treatment was done less frequently in accordance with the treatment recommendations (< 60 years 83-89%; 60-74 years 67-77%; > or = 75 years 29-36% according to stage and tumor localization); in stage IV, the use of chemotherapy was reduced (< 60 years 87.5-100%; 60-74 years 38-47%; > or = 75 years 33-37%). In the univariate analysis, age > or = 75 years (4-year survival rates: < 60 years 68 +/- 4.1%; 60-74 years 58 +/- 2.8%; > or = 75 years 38 +/- 3.7%), UICC stage and surgical treatment had a significant effect on prognosis. Adjuvant treatment had no significant effect on the whole population but on patients with UICC stage III and IV. In the multivariate analysis, however, the only independent prognostic parameters were age > or = 75 years (p = 0.001), performance of chemotherapy (colon cancer) or radiochemotherapy (rectal cancer; p = 0.004-0.001), and tumor stage (p = 0.045-0.001). Sex (p = 0.063) and age between 60 and 74 years (p = 0.067) had a borderline influence. CONCLUSION: With increasing age, there is a departure in daily practice from the treatment recommendations. The patient's prognosis is dependent upon age (especially > or = 75 years), tumor stage, and therapy.