Gastric cancer (GC) represents a leading cause of cancer related morbidity and mortality worldwide accounting for more than 1 million of newly diagnosed cases and thousands of deaths every year. In ...the last decade, the development of targeted therapies and the optimization of already available chemotherapeutic drugs has expanded the available treatment options for advanced GC and granted better survival expectations to the patients. At the same time, global efforts have been undertaken to investigate in detail the genomic and epigenomic heterogeneity of this disease, resulting in the identification of new specific and sensitive predictive and prognostic biomarkers and in innovative molecular classifications based on gene expression profiling. Nonetheless, several randomized studies aimed at exploring new innovative agents, such as immune checkpoint inhibitors, failed to demonstrate clinically meaningful survival advantages. Therefore, it is essential to further improve the molecular characterization of GC subgroups in order to provide researchers and medical oncologists with new tools for patients' selection and stratification in future clinical development programs and subsequent trials. The aim of the present manuscript is to provide a global overview of the recent molecular classifications from The Cancer Genome Atlas and the Asian Cancer Research Group and to present key promising developments in the field of immunotherapy and targeted therapies in metastatic GC.
Colorectal cancer (CRC) is a complex and molecularly heterogeneous disease representing one of the most frequent causes of cancer-related death worldwide. About 8-15% of CRCs harbor a mutation in
...gene, a proto-oncogene involved in cell proliferation, differentiation and survival through the MAPK signaling cascade. The acquisition of
mutation is an early event in the "serrated" CRC carcinogenetic pathway and is associated with specific and aggressive clinico-pathological and molecular features. Despite that the presence of
mutation is a well-recognized negative prognostic biomarker in metastatic CRC (mCRC), a great heterogeneity in survival outcome characterizes these patients, due to the complex, and still not completely fully elucidated, interactions between the clinical, genetic and epigenetic landscape of
mutations. Because of the great aggressiveness of
-mutated mCRCs, only 60% of patients can receive a second-line chemotherapy; so intensive combined and tailored first-line approach could be a potentially effective strategy, but to minimize the selective pressure of resistant clones and to reduce side effects, a better stratification of patients bearing
mutations is needed.
PD-L1 expression in gastroesophageal dysplastic lesions Fassan, Matteo; Brignola, Stefano; Pennelli, Gianmaria ...
Virchows Archiv : an international journal of pathology,
07/2020, Letnik:
477, Številka:
1
Journal Article
Recenzirano
Immunotherapy has been recently approved for gastric (GC) and gastroesophageal-junction adenocarcinomas (GEC), and PD-L1 immunohistochemical evaluation represents a promising predictive biomarker in ...this oncological setting. A series of 125 gastroesophageal dysplastic lesions (52 low-grade, 73 high-grade) was investigated for PD-L1 and DNA mismatch repair proteins status. PD-L1 was positive (combined positive score (CPS) ≥ 1) in 48 (31.0%) dysplastic lesions. A higher prevalence of PD-L1–positive cases was observed among esophageal specimens compared with gastric ones (
p
= 0.0003), in high-grade and adenocarcinoma samples in comparison with low-grade dysplasia (
p
< 0.0001), and in lesions with mismatch repair deficiency (
p
= 0.028). For 30 dysplastic samples, a synchronous matched invasive lesion (GC = 15, GEC = 15) was available and tested for PD-L1 expression; a discordant PD-L1 status was observed in 12/30 (40%) cases. A relatively high prevalence in PD-L1 positivity was observed among gastroesophageal dysplastic lesions and this should be taken into consideration for future therapeutic strategies based on this biomarker.
The tight junction protein claudin-18 (CLDN18), is often expressed in various cancer types including gastric (GC) and gastroesophageal adenocarcinomas (GECs). In the last years, the isoform CLDN18.2 ...emerged as a potential drug target in metastatic GCs, leading to the development of monoclonal antibodies against this protein. CLDN18.2 is the dominant isoform of CLDN18 in normal gastric and gastric cancer tissues. In this work, we evaluated the immunohistochemical (IHC) profile of CLDN18 and its correlation with clinical and histopathological features including p53, E-cadherin, MSH2, MSH6, MLH1, PMS2, HER2, EBER and PD-L1 combined positive score, in a large real-world and mono-institutional series of advanced GCs (n = 280) and GECs (n = 70). The association of IHC results with survival outcomes was also investigated. High membranous CLDN18 expression (2+ and 3+ intensity ≥75%) was found in 117/350 (33.4%) samples analyzed. CLDN18 expression correlated with age <70 (p = 0.0035), positive EBV status (p = 0.002), high stage (III, IV) at diagnosis (p = 0.003), peritoneal involvement (p < 0.001) and lower incidence of liver metastases (p = 0.013). CLDN18 did not correlate with overall survival. The predictive value of response of CLDN18 to targeted agents is under investigation in several clinical trials and further studies will be needed to select patients who could benefit from these therapies.
Longstanding/relapsing inflammation characterizing ulcerative colitis (UC) has been associated to an increased risk of colon mucosa neoplastic transformation. We describe the clinicopathological ...features of a UC-related poorly-differentiated neuroendocrine carcinoma coexisting with a conventional adenocarcinoma. This case supports UC as a multilineage cancerization field.
Claudin-18 (CLDN18) is a highly specific tight junction protein of the gastric mucosa. An isoform of CLDN18, the Claudin 18.2, has recently emerged as an innovative drug target for metastatic gastric ...cancer.
We investigated the immunohistochemical profile of CLDN18, p53, p16, E-cadherin, MSH2, MSH6, MLH1, PSM2, HER2, and PDL-1 in a large series of 523 primary gastric carcinomas (GCs; n = 408) and gastro-oesophageal carcinomas (GECs; n = 115) and 135 matched and synchronous nodal metastases. The status of HER2 and EBER by means of chromogenic in situ hybridisation (CISH) was also evaluated.
High membranous CLDN18 expression was present in 150/510 (29.4%) primary cases and in 45/132 (34.1%) metastases. An abnormal expression (i.e. nuclear and/or cytoplasmic) was observed in 115 (22.5%) primary cases and in 33 (25.0%) metastases. A 38.8% of the cases showed significant CLDN18 intratumoural variability among the different tissue microarray cores obtained from the same tumour. Positive membrane CLDN18 expression was statistically associated with non-antral GCs (p = 0.016), Lauren diffuse type (p = 0.009), and with EBV-associated cancers (p < 0.001).
CLDN18 is frequently expressed in gastric and gastro-oesophageal cancers; further studies should investigate the prognostic significance of CLDN18 heterogeneity in order to implement its test into clinical practice.
FGFR2 rearrangements have been identified as a novel therapeutic target of biliary tract cancer (BTC). However, reliable prevalence estimates of this molecular alteration and its prognostic role have ...not been fully elucidated.
A retrospective mono-institutional series of 286 patients affected by locally advanced or metastatic BTC (183 intrahepatic cholangiocarcinomas, 67 extrahepatic cholangiocarcinomas, 36 gallbladder carcinomas) was profiled by means of targeted DNA/RNA next-generation sequencing, immunohistochemistry and fluorescence in situ hybridisation for FGFR2/3, ERBB2, NTRK alterations, IDH1/2 and BRAF mutations and DNA mismatch repair complex proteins alterations/microsatellite instability.
FGFR2 rearrangements, amplifications and point mutations were detected in 15 (5.2%), 1 and 3 cases, respectively. FGFR3 alterations were observed in 5 (1.7%) cases. IDH1/2 were mutated in 35/223 cases (15.7%). A total of 9/258 (3.5%) and 6/260 (2.3%) BTCs had ERBB2 and BRAF gene alterations, respectively. Two cases (2/242; 0.8%) had NTRK1 amplifications but no rearrangement was found. A deficit of mismatch repair protein expression was identified in 9/237 cases (3.8%). At multivariate analysis, age, ECOG performance status, number of metastatic sites, tumour stage, FGFR2/3 alterations and IDH1/2 mutations were prognostic factors of overall survival.
These data provide a strong proof – challenged with a robust and detailed multivariate model – that FGFR2/3 aberrations (including FGFR2 rearrangements) and IDH1/2 mutations can be prognostic for better survival in patients with BTC . The recognition and the measurement of their prognostic impact could be of primary importance for the correct interpretation of currently available data and in the design of new therapeutic trials.
•FGFR2 rearrangements are a novel therapeutic target in biliary tract cancer.•FGFR2/3 aberrations and IDH1/2 mutations are prognostic for better survival.•FGFR2/3 prognostic impact should be considered in the design of therapeutic trials.
Benign terminal deoxynucleotidyl transferase (TdT)–positive cells have been documented in a variety of nonhematopoietic tissues. Scant data are, however, available on their presence in nonneoplastic ...lymph nodes. This study is aimed to (1) characterize the presence/distribution of benign TdT-positive cells in pediatric and adult reactive lymph nodes and (2) define the phenotype and nature of such elements. This retrospective study considered 141 reactive lymph nodes from pediatric and adult patients without history of neoplastic disease. TdT-positive cells were characterized by immunohistochemical and morphometric analyses, and their presence was correlated with the clinical-pathological features. The nature of TdT-positive cells was investigated by (1) double immunostaining for early lymphoid cell markers and (2) assessment of TdT expression in fetal lymph nodes. Sparse TdT-positive cells were documented in all pediatric cases and in most (76%) adult lymph nodes. TdT-positive cell density was higher in children than adults (15.9/mm2 versus 8.6/mm2; P < .05). TdT positivity did not correlate with any clinical or histological parameter, and double immunostaining disclosed a phenotype compatible with early lymphoid precursors (positivity for CD34 and CD10, and variable expression of CD7). A very high TdT-positive cell density (802.4/mm2) was reported in all fetal lymph nodes. In conclusion, TdT-positive cells are a common finding in pediatric and adult lymph nodes. The interstitial distribution and low number of such cells allow for the differential diagnosis with precursor lymphoid neoplasms. The high density in fetal lymph nodes and the phenotype of such cells suggest their belonging to an immature lymphoid subset gradually decreasing with age.
•Scattered TdT-positive cells are very common in pediatric and adult lymph nodes.•The prevalence and density of TdT-positive cells are higher in children than adults.•TdT-positive cells disclose the phenotype of CLPs.•The awareness of these cells prevents their misdiagnosis as precursor lymphoid neoplasms.
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