Mismatch Repair Protein Status Research Articles

The Relationship Between DNA Mismatch Repair Status and Clinicopathologic Characteristics in Colon Cancer.

DNA mismatch repair (MMR) proteins are essential for repairing genetic mutations that occur during DNA replication. Deficiency of MMR proteins results in a phenotype called microsatellite instability (MSI), which occurs in Lynch syndrome as well as sporadic colorectal cancers (CRC), and it is associated with several clinicopathological features. We aimed to investigate the association of the loss of MMR proteins with clinicopathologic considerations in our CRC series. In this retrospective study, DNA MMR protein status in CRC is evaluated in a total of 200 colorectal resection specimens by immunohistochemistry (IHC) for MLH1, MSH2, MSH6 and PMS2 protein expression. The BRAF mutation was investigated by the real-time PCR in cases with loss of MLH1 protein expression. The relationship between MMR status and clinicopathological parameters was investigated statistically. Loss of MMR protein expression was detected in 26 of 200 CRC cases. The BRAFV600E mutation was detected in 2 of the cases with MLH1 loss and accepted as sporadic. The remaining 24 cases (12%) were identified as Lynch syndrome candidates. There were statistical differences observed regarding the presence of tumor-infiltrating lymphocytes (P < .001), Crohn's-like reaction (P = .001), expansile growth (P < .001), tumor heterogeneity (P < .001), mucinous differentiation (P < .001), and presence of metastatic lymph nodes (P = .045) between sporadic cases with preserved MMR and Lynch candidates. However, difference in the survival rates between sporadic cases and Lynch candidates was not significant. Immunohistochemical staining for MMR is a practical method for predicting MSI phenotype as well as Lynch candidates. MMR expression status was found to be associated with certain clinicopathological features some of which also have prognostic significance.

FREQUENCY OF LOSS OF MISMATCH REPAIR PROTEINS’ IMMUNOHISTOCHEMICAL EXPRESSION IN SEBACEOUS NEOPLASMS, POTENTIAL MARKERS/TOOLS INDICATING THE POSSIBILITY OF MUIR-TORRE SYNDROME

Screening for Muir-Torre Syndrome (MTS) using Mismatch Repair (MMR) gene immunohistochemistry (IHC) on sebaceous neoplasms (SNs) is technically feasible. Research for this indication is limited, especially in Asia. To address this knowledge gap, we examined the frequency of loss of IHC staining of MMR proteins in SNs. Methods: We conducted a cross-sectional study including 98 patients (120 SNs). Eleven out of 98 patients had concurrent or subsequent SNs. Results: The size and type of tumor showed a significant association with MMR loss. Fifteen (12.5%) sebaceous adenomas, 12 (10.0%) sebaceous, and 93 (77.5%) sebaceous carcinomas were included in the study—sixty-one (50.83 %) SNs presented with loss of one or more MMR proteins. Isolated loss of MSH2 was the most common IHC pattern (27.8%). Fifty cases (29.58%) showed a combined loss of MSH2 and MSH6, and 40 (23.66%) showed a combined loss of MLH1 and PMS2. Most SAs showed isolated loss of MLH1 and PMS2 (7, 26.9% each). Sebaceomas showed isolated loss of MSH2 and MSH6 as the most common (4, 33.3%) pattern. Isolated loss of MSH2 only (37, 28.2%) was the predominant pattern of IHC loss in SCs. Weak to fragile associations between MMR protein status and histopathological findings were observed, with the most notable association being between MLH1 and ulceration on the surface. The models have an accuracy of around 50%, indicating moderate prediction capability. In our cohort, personal and family history was available in 33 cases (25 out of 98 patients). Conclusion: We recommend that MMR IHC be performed routinely on all SNs, considering clinicopathological factors of the lesions, mainly the anatomic site and tumor type. The panel should include antibodies against all four MMR proteins.

Comparing Clinicopathological and Immunohistochemical Features of Colorectal Carcinoma between Young and Old Age Groups.

The incidence of colorectal carcinoma (CRC) is increasing among individuals younger than 50, and some studies suggest the presence of differences in CRC among old and young individuals regarding clinical and histopathological features. The aim of this study was to compare clinicopathological features, mismatch repair protein status, and expression of certain immunohistochemical stains between young and old groups. The study included 180 cases and found significant histological and immunohistochemical differences between the two groups. CRC in the young tends to be more right-sided and has a higher percentage of dMMR proteins, but less expression of p53 mutations. These features are commoner in Lynch syndrome, and more investigations to study the relationship between young-onset CRC and hereditary syndromes are needed. Young-onset CRC also tends to show higher expression of tumor cell PD-L1, which is an expected finding, as dMMR cases are more likely to be immunogenic. Two other significant differences are the higher percentage of mucinous carcinoma and the higher tumor grade in young-onset CRC. These two features suggest a more advanced disease with possibly worse outcomes; however, there is no difference in disease stage between the two age groups.

Effect of preoperative immune checkpoint inhibitors on reducing residual lymph node metastases in patients with gastric cancer: a retrospective study

Objective: To investigate the effect of immune checkpoint inhibitors on reducing residual lymph node metastasis in patients with gastric cancer. Methods: The cohort of this retrospective study comprised patients from Nanfang Hospital of Southern Medical University and the First Affiliated Hospital of Xiamen University who had undergone systemic treatment prior to gastrectomy with D2 lymphadenectomy and had achieved Grade 1 primary tumor regression (TRG1) from January 2014 to December 2023. After exclusion of patients who had undergone preoperative radiotherapy, data of 58 patients (Nanfang Hospital: 46; First Affiliated Hospital of Xiamen University: 12) were analyzed. These patients were allocated to preoperative chemotherapy (Chemotherapy group, N=36 cases) and preoperative immunotherapy plus chemotherapy groups (Immunotherapy group, N=22 cases). There were no significant differences between these groups in sex, age, body mass index, diabetes, tumor location, pathological type, Lauren classification, tumor differentiation, pretreatment depth of invasion by primary tumor, pretreatment lymph node stage, pretreatment clinical stage, mismatch repair protein status, number of preoperative treatment cycles, or duration of preoperative treatment (all P>0.05). The primary outcome measure was postoperative lymph node downstaging. Secondary outcomes included postoperative depth of invasion by tumor, number of lymph nodes examined, and factors affecting residual lymph node metastasis status. Results: Lymph node downstaging was achieved significantly more often in the Immunotherapy group than the Chemotherapy group (pN0: 90.9% [20/22] vs. 61.1% [22/36]; pN1: 4.5% [1/22] vs. 36.1% [13/36]; pN2: 4.5% [1/22) vs. 0; pN3: 0 vs. 2.8% [1/36], Z=-2.315, P=0.021). There were no significant difference between the two groups in number of lymph nodes examined (40.5±16.3 vs. 40.8±17.5, t=0.076, P=0.940) or postoperative depth of invasion by primary tumor (pT1a: 50.0% [11/22] vs. 30.6% [11/36]; pT1b: 13.6% [3/22] vs. 19.4% [7/36]; pT2: 13.6% [3/22] vs. 13.9% [5/36]; pT3: 13.6% [3/22] vs. 25.0% [9/36]; pT4a: 9.1% [2/22] vs. 11.1% [4/36], Z=-1.331, P=0.183). Univariate analysis revealed that both preoperative treatment regimens were associated with residual lymph node metastasis status in patients whose primary tumor regression was TRG1 (χ2=6.070, P=0.014). Multivariate analysis incorporated the following factors: pretreatment depth of invasion by primary tumor, pretreatment lymph node stage, pretreatment clinical stage, number of preoperative treatment cycles, and preoperative treatment duration. We found that a combination of immunotherapy and chemotherapy administered preoperatively was an independent protective factor for reducing residual lymph node metastases in study patients whose primary tumor regression was TRG1 (OR=0.147, 95%CI: 0.026-0.828, P=0.030). Conclusion: Compared with preoperative chemotherapy alone, a combination of preoperative immunotherapy and chemotherapy achieved greater reduction of residual lymph node metastases in the study patients who achieved TRG1 tumor regression in their primary lesions.

Prognostic evaluation of KRAS and BRAF mutations in relation to Mismatch Repair protein status: preliminary survival analysis of patients with Colorectal Cancer

Aims: prognostic impact of mutations in BRAF and KRAS genes in patients with colorectal cancer was evaluated to detect variations in survival among patients with these mutations, in relation to different morphologic features identified at diagnosis and the expression of mismatch repair proteins. The final purpose of the project will be to establish models to predict variations in survival in different subsets of patients with colorectal cancer. Materials and Methods: partial survival analyses were conducted on 32 subjects in relation to three different variables: mutation in BRAF or KRAS genes, expression of mismatch repair system and morphological features of the tumor. Results: preliminary results of this study provide evidence that survival in different subsets of patients with colorectal cancer can be influenced by several factors, which include, in addition to immunohistochemical and molecular investigations, the assessment of different morphological features. Conclusions: Integrating different characteristics may reveal which factors have a more significant impact on survival in these subgroups. More patients will be needed to design different survival models and to check these preliminary results more effectively.

HER2-low and Overexpression in Mucinous Ovarian Cancer: Analysis of ASCO/CAP and ToGA Immunohistochemical Scoring.

Mucinous ovarian carcinoma is an uncommon malignancy characterized by resistance to chemotherapy and poor survival in the metastatic setting. HER2 amplification is a frequent late event in carcinogenesis, yet the incidence of HER2-low in mucinous ovarian carcinoma is unknown. Further, the optimal method for determining overexpression in these tumors is not established. We sought to assess the ASCO/CAP and ToGA trial scoring methods for HER2 IHC with correlation to FISH, p53, and mismatch repair protein status and to determine the incidence of HER2-low in mucinous ovarian carcinoma. A total of 29 tumors from 23 patients were included. Immunohistochemistry for HER2, p53, MLH1, PMS2, MSH2, and MSH6 was performed. Scoring was performed according to the ASCO/CAP and ToGA trial criteria. HER2 FISH was performed and scored according to the ASCO/CAP criteria. The proportion of HER2-low, defined as 1+ or 2+ staining with negative FISH, was determined. Using ASCO/CAP, 26% demonstrated 3+ while 35% demonstrated 2+ staining. Using ToGA, 30% demonstrated 3+ while 57% demonstrated 2+ staining. By FISH, 26% were positive for HER2 amplification. Both systems captured all FISH-positive cases; the use of ASCO/CAP resulted in fewer equivocal and false-positive cases. Among HER2-negative cases, 88% were HER2-low. Aberrant p53 expression was detected in 55% of cases; mismatch repair deficiency was not identified in any cases. ASCO/CAP guidelines are accurate and resource-effective in determining HER2 overexpression in mucinous ovarian carcinoma. HER2-low is common in these tumors; further studies to determine the role of HER2-targeted therapy including antibody-drug conjugates are indicated.

Causes of death in patients operated for colorectal cancer

BackgroundColorectal cancer remains the third leading cause of cancer-related mortality in the United States. This study evaluates the causes of death in patients operated on for colorectal cancer and their determinants. MethodsAn Instructional Review Board-approved database containing patients who underwent surgical resection for colorectal cancer from 2004 to 2018 (last followed up in December 2020) in a tertiary care institution. Data on the underlying cause of death was extracted from the Registry of Vital Records and Statistics in Massachusetts. ResultsA total of 576 deaths were recorded in the database, of which 290 (50.35%) patients died of colorectal cancer. Deaths from colorectal cancer gradually decreased over time, whereas deaths from other cancers increased, and deaths from cardiovascular diseases remained stable. Patients who died from colorectal cancer were younger, died earlier in the disease course, had fewer comorbidities, higher rates of stage IV disease, rectal cancer, neoadjuvant therapy, extramural vascular invasion, perineural invasion, R0 resection, and preserved mismatch repair protein status. On multivariate analysis, age (adjusted odds ratio for 10-year increase = 0.79, 95% confidence interval 0.65–0.95), American Society of Anesthesiologists score (adjusted odds ratio = 0.64, confidence interval 0.42–0.98), stage IV disease (adjusted odds ratio = 3.02, confidence interval 1.59–5.9), neoadjuvant therapy (adjusted odds ratio = 7.91, confidence interval 2.64–28.13), extramural vascular invasion (adjusted odds ratio = 2.3, confidence interval 1.36–3.91) & time from diagnosis to death (adjusted odds ratio = 0.76, confidence interval 0.68–0.83) predicted death due to colorectal cancer versus other causes, whereas tumor location, perineural invasion, R0 resection, and mismatch repair protein status did not. ConclusionThere is a declining trend of deaths from colorectal cancer, presumably reflecting advances in colorectal cancer management strategies and better screening over time. However, younger patients disproportionately contribute to death due to colorectal cancer and need aggressive screening and management strategies.

The Correlation between Tumour Location, Clinicopathological Characteristics and Mismatch Repair Protein (MMR) Status of Colorectal Cancer In Egyptian Patients

Background: Colorectal cancer (CRC) is considered one of the most common cancers worldwide. By the year of 2035, it is predicted that there will be a dramatic rise of colonic and rectal cancers of 60% and 71.5% respectively. It has been reported that microsatellite instability (MSI) is a genetic target in hereditary nonpolyposis colorectal cancer cases however recent studies have shown that it is also implicated in the development of sporadic cases. MSI/MMR mutations can stimulate tumourigenesis by inactivating tumour suppressor genes and cases with high or deficient MMR (dMMR) have shown a better clinical outcome and response to programmed cell death 1 (PD-1) inhibitors in many studies. Furthermore, right and left sided colon cancers have different clinicopathological features and may display a different MMR status. Aim of the work: This work aimed to examine immunohistochemical expression of MMR proteins in colorectal tumours of Egyptian patients and their correlation with the age, sex, tumour grade, histological type and TNM stage to implicate possible therapeutic and prognostic potential. Material and Methods: This retrospective study was conducted on 409 cases of archived, formalin fixed paraffin embedded tissue blocks and immunohistochemical staining was performed using monoclonal antibodies against (MLH1, PMS2, MSH2 and MSH6). Results: MMR protein expression revealed intact expression (MMR-proficient status) in (84.4%) of the cases while (15.6%) of the cases showed lost protein expression. MMR protein loss was seen more frequently in patients with right side colon cancer compared to left side counterparts and this was statistically highly significant (p=0.001*). MLH1/PMS2 loss was the most frequent pattern while MSH2/MSH6 loss was less frequent. Moreover, a statistically significant correlation was demonstrated between loss of MLH1 and PMS2 among right-side tumours, while left-side CRC tumours revealed obvious loss MSH2 and MSH6. In regards to age and gender, a statistically significant correlation was seen regarding loss of MSH2 (p=0.008*) and MSH6 (p=0.002*). In thirty-eight cases, PMS2 was lost and showed a positive correlation regarding grade (p=0.045*). These results have shown the difference in MMR status of right and left sided colorectal cancers and the potential prognostic and therapeutic impact. Conclusion: The frequency of mismatch repair deficiency (dMMR) status in this cohort study carried on Egyptians’ CRC cases was 15.6%. It showed varying expression in right sided CRC in comparison to Left sided ones. The different biological factors regarding right and left sided colonic cancers may be used to identify cases who needs screening and further management.

PD-L1 Expression in Colorectal Carcinoma: A Comparison of 3 Scoring Methods in a Cohort of Jordanian Patients.

Anti-programmed death-ligand 1 (PD-L1) treatments can improve colorectal carcinoma (CRC) survival; however, there is still controversy regarding the relationship between PD-L1 expression and the outcome of immunotherapeutic treatment and survival. The discrepancies are partly caused by the lack of a unified scoring system. This retrospective, cross-sectional study evaluated PD-L1 by immunohistochemistry in 127 CRC cases and compared the 3 scoring systems used to assess PD-L1: Tumor Percentage Score (TPS), Combined Positive Score (CPS), and immune cell (IC) score. Correlations were calculated using the χ 2 test. Kaplan-Meier curves with the Log-rank test were used to measure the contribution of PD-L1 expression to survival. PD-L1-positive rate were 29.9%, 57.5%, and 55.9% based on TPS, CPS, and IC score, respectively. TPS showed a better correlation with the clinicopathologic features being significantly higher with young age, T4, and adenocarcinomas (compared with mucinous/signet ring). TPS also showed an increasing trend with higher grade, lymph node stage, and male sex, although these variables were not significantly associated with PD-L1 expression. There was no correlation between PD-L1 expression and mismatch repair protein status in the 3 scoring methods. The probability of survival was higher for PD-L1-negative cases in the first 60 months after surgery if scored by the TPS method ( P =0.058). Future efforts correlating PD-L1 status with response to treatment are needed to decide on the best scoring method to be used for making therapy decisions.

Clinicopathological characteristics of endometrial carcinomas according to DNA mismatch repair protein status

DNA mismatch repair protein deficiency (MMRd) in endometrial carcinoma is associated with the risk of Lynch syndrome and response to immune checkpoint inhibitors. It is also related to microsatellite instability and corresponds to a molecular subtype of endometrial tumor with an unclear prognosis. Here, we evaluated the clinicopathological characteristics and prognosis of 312 consecutive endometrial carcinoma cases submitted to complete surgical staging at a single institution. We compared MMRd and mismatch repair protein–proficient (MMRp) tumors and examined the effects of the MMR protein loss type (MLH1/PMS2 vs. MSH2/MSH6) and influence of L1CAM and p53 expression. The median follow-up period was 54.5 (range, 0–120.5) months. No difference was observed between MMRd [n = 166 (37.2%)] and MMRp [n = 196 (62.8%)] cases in terms of age, body mass index, FIGO stage, tumor grade, tumor size, depth of myometrial infiltration, or lymph node metastasis. More MMRd than MMRp tumors had endometrioid histology (87.9% vs. 75.5%) and despite MMRd had more lymphovascular space invasion (LVSI; 27.2% vs. 16.9%), they presented fewer recurrences and no difference in lymph node metastasis and disease-related death. Relative to those with MLH1/MSH6 loss, tumors with MSH2/MSH6 loss were diagnosed at earlier FIGO stages, were smaller, and had less ≥50% myometrial invasion, LVSI and lymph node metastasis. Outcomes, however, did not differ between these groups. L1CAM positivity and mutation-type p53 expression were more common in MMRp than in MMRd tumors and did not differ between the MLH1/PMS2 and MSH2/MSH6 loss groups. In the entire cohort, L1CAM and mutation p53 expression were associated with worse prognosis, but only non-endometrioid histology, FIGO stage III/IV, and deep myometrial infiltration were significant predictors. In the subgroup of endometrioid carcinomas, only FIGO stage III/IV was associated with poor outcomes. The risk of lymph node metastasis was associated with tumor size, non-endometrioid histology, and multifocal LVSI. For MMRd tumors, only tumor size and myometrial invasion depth were predictive of lymph node involvement. In our cohort, MMRd tumors were associated with greater recurrence-free, but not overall, survival. The precise identification of MMRd status, present in a substantial proportion of endometrial cancer cases, is a challenge to be overcome for proper patient management. MMRd status serves as a marker for Lynch syndrome, and a significant number of these tumors are high risk and candidate to immunotherapy.

Mismatch repair protein status of non-neoplastic uterine and intestinal mucosa in patients with Lynch syndrome and double somatic mismatch repair protein mutations

Mismatch repair (MMR) protein-deficient non-neoplastic colonic crypts and endometrial glands (dMMR crypts and glands) have been reported as a unique marker of underlying Lynch syndrome (LS). However, no large studies have directly compared the frequency of detection in cases with double somatic (DS) MMRmutations. We retrospectively analyzed 42 colonic resection specimens (24 LS and 18 DS) and 20 endometrial specimens (9 LS and 11 DS), including 19 hysterectomies and 1 biopsy for dMMR crypts and glands. All specimens were from patients with known primary cancers, including colonic adenocarcinomas and endometrial endometrioid carcinomas (including 2 mixed carcinomas). Four blocks of normal mucosa away from the tumor were selected from most cases, as available. MMR immunohistochemistryspecific to the primary tumor mutations was analyzed. dMMR crypts were found in 65% of LS and 0% of DS MMR-mutated colonic adenocarcinomas (P<.001). Most dMMR crypts were detected in the colon (12 of 15) compared to the ileum (3 of 15). dMMR crypts showed single and grouped losses of MMR immunohistochemical expression. dMMR glands were found in 67% of LS and 9% (1 of 11) of DS endometrial cases (P=.017). Most dMMR glands were found in the uterine wall, with 1LS and 1 DS case exhibiting dMMR glands in the lower uterine segment. Most cases exhibited multifocal and grouped dMMR glands. No morphologic atypia was identified in dMMR crypts or glands. Overall, we demonstrate that dMMR crypts and glands are highly associated with underlying LS, while being rarer in those with DS MMR mutations.

Risk factors for lymph node metastasis in patients with pT2 colon cancer in Denmark from 2016 to 2019-A nationwide cohort study.

The majority of patients with pT2 colon cancer have no lymph node metastasis (LNM). Knowledge of risk factors for LNM in pT2 colon cancer could identify patients at low risk and thereby potential candidates for local tumour excision. The aim of this work was to identify risk factors for LNM in pT2 colon cancer and describe a subgroup of low-risk patients. This is a retrospective cohort study of patients with pT2 colon cancer from a nationwide Danish colorectal cancer database. Age, tumour size, location, histological type, mismatch repair protein status and venous, lymphatic and perineural invasion were included as potential risk factors in multivariate analysis. The primary outcome was LNM. We identified 1306 patients with pT2 colon cancer. LNM was present in 244 (19%). Demographic data were comparable in patients with and without LNM, and 864 patients who had complete histological data were included for multivariate analysis. Lymphatic (OR=3.60, 95% CI 2.14-5.9), venous (OR=1.70, 95% CI 1.03-2.74) and perineural (OR=4.61, 95% CI 1.60-13.5) invasion were independent risk factors for LNM. Patients with deficient mismatch repair protein tumours had a decreased risk of LNM (OR=0.55, 95% CI 0.31-0.95). Patients with clinical Stage I colon cancer and without risk factors had a 10.5% (47/443) risk of LNM. For patients with tumours with deficient mismatch repair protein status and no risk factors, the risk was 7.9%. Lymphatic, venous and perineural invasion are significant risk factors for LNM, and we identified a subgroup of patients with a low risk of LNM.

Prognostic value of tumor budding in patients with stage II and III colon cancer: A single-institution experience.

247 Background: Tumor budding has recently been recognized as one important prognostic factor for recurrence in patients with localized colon cancer. Nevertheless, not all guidelines consider tumor budding in the decision-making process for selecting patients for adjuvant chemotherapy. We aim to assess the prognostic value of tumor budding in a cohort of patients with stage II and III colon cancer. Methods: We included patients with pathologically confirmed diagnosis of stage II and III colon cancer at Hospital Universitario La Paz and tumor budding assessment available, from October 2016 to August 2021. Tumor budding was reported following the recommendations from the 2016 International Tumour Budding Consensus Conference. Results: A total of 390 patients were included. Patients were predominantly men (55%) and had a median age of 75 (35-95). Fifty percent of the patients were stage II and 50% were localized in the right colon. Tumor budding was reported as low, intermediate, and high in 186 (48%), 110 (28%), and 94 (24%) patients, respectively. After a median follow up of 18 months, 63 recurrences and 73 deaths were observed. Time to recurrence was significantly worse for patients with high tumor budding. At 24 months, 91%, 79%, and 67% of patients with low, intermediate and high budding were recurrence-free. Median TTR was not reached in any of the three cohort (P &lt;0.001). Comparing high vs low or intermediate budding, the hazard ratio (HR) for recurrence was 0.13 [confidence interval (CI)95%: 0.05 to 0.32; P &lt; 0.001]. We performed a univariate analysis with the most relevant clinic-pathological features. T4, N2, R1, bowel obstruction or perforation, positive resection margins (R1), lymphovascular or perineural invasion, and mismatch repair protein status were found to be statistically associated with TTR and entered the multivariate analysis. T4, N2, R1 and high tumor budding (HR: 0.48 [CI95%: 0.28 to 0.84], P = 0.011) were independent prognostic factors for recurrence at the multivariate analysis. Conclusions: High tumor budding is an adverse independent prognostic factor for recurrence in patients with stage II and III colon cancer and should be acknowledge when considering adjuvant chemotherapy.

Histopathologic Features for Overall Survival in Merkel Cell Carcinoma: A Case Series with Intact Mismatch Repair Protein Expression.

In a study of Merkel cell carcinoma (MCC), a fusion transcript between MLH1 and SPATA4 was identified. This fusion has the potential to generate the inactive or dominant-negative form of the protein. Therefore, we aimed to investigate whether mismatch repair protein deficiency occurr in MCC cases or not, in addition to the overall survival association with histopathologic features. A retrospective review of 15 patients diagnosed with a biopsy-proven Merkel Cell Carcinoma between 2012 and 2019 was performed. Mismatch repair (MMR) protein expressions were evaluated by immunohistochemistry. The median follow-up time was 36 months (mean 41, range 2-103 months). Six (40%) patients died during follow-up. The overall survival (OS) at 1 year, 2 years, 3 years, and 5 years were 87%, 80%, 62%, and 53%, respectively. The patients diagnosed at < 60 years had an improved OS compared to those ≥60 years of age (p=0.016). Patients in clinical stage I had better OS than patients in clinical stage IV (p=0.011). Cases with pathological tumor stage (pT) 1 had better OS than pT3 and pT4 (p=0.045). Adjuvant radiotherapy or adjuvant radiotherapy+chemotherapy treatment improved OS compared to adjuvant chemotherapy (p=0.003). MMR protein nuclear expression was intact in 12 cases available for immunohistochemical study. To the best of our knowledge, this is the second study that preferentially investigated the mismatch repair protein status of Merkel Cell Carcinoma. No mismatch repair protein deficiency of MCC cases was identified in the current study.

Protein biomarkers in cervicovaginal lavages for detection of endometrial cancer

BackgroundRates of endometrial cancer (EC) are increasing. For a definitive diagnosis, women undergo various time-consuming and painful medical procedures, such as endometrial biopsy with or without hysteroscopy, and dilation and curettage, which may create a barrier to early detection and treatment, particularly for women with inadequate healthcare access. Thus, there is a need to develop robust EC diagnostics based on non- or minimally-invasive sampling. The objective of this study was to quantify a broad range of immuno-oncology proteins in cervicovaginal lavage (CVL) samples and investigate these proteins as predictive diagnostic biomarkers for EC.MethodsOne hundred ninety-two women undergoing hysterectomy for benign or malignant indications were enrolled in this cross-sectional study. Classification of women to four disease groups: benign conditions (n = 108), endometrial hyperplasia (n = 18), low-grade endometrioid carcinoma (n = 53) and other EC subtypes (n = 13) was based on histopathology of biopsy samples collected after the surgery. CVL samples were collected in the operating room during the standard-of-care hysterectomy procedure. Concentrations of 72 proteins in CVL samples were evaluated using multiplex immunoassays. Global protein profiles were assessed using principal component and hierarchical clustering analyses. The relationships between protein levels and disease groups and disease severity were determined using Spearman correlation, univariate and multivariate receiver operating characteristics, and logistic regression analyses.ResultsWomen with EC and benign conditions exhibited distinctive cervicovaginal protein profiles. Several proteins in CVL samples (e.g., an immune checkpoint protein, TIM-3, growth factors, VEGF, TGF-α, and an anti-inflammatory cytokine, IL-10) discriminated EC from benign conditions, particularly, when tested in combinations with CA19–9, CA125, eotaxin, G-CSF, IL-6, MCP-1, MDC, MCP-3 and TRAIL (sensitivity of 86.1% and specificity of 87.9%). Furthermore, specific biomarkers (e.g., TIM-3, VEGF, TGF-α, TRAIL, MCP-3, IL-15, PD-L2, SCF) associated with histopathological tumor characteristics, including histological type and grade, tumor size, presence and depth of myometrial invasion or mismatch repair protein status, implying their potential utility for disease prognosis or monitoring therapies.ConclusionsThis proof-of-principle study demonstrated that cervicovaginal sampling coupled with multiplex immunoassay technology can offer a minimally to non-invasive method for EC detection.

The prognostic impact of the immune microenvironment in small-cell neuroendocrine carcinoma of the uterine cervix: PD-L1 and immune cell subtypes

BackgroundWe investigate the correlation between programmed cell death-ligand 1 (PD-L1) and tumor-associated immune cell (TAIC) density in small-cell neuroendocrine carcinoma of the uterine cervix (SCNEC) and their correlation with clinicopathologic features.MethodsPD-L1 and mismatch repair protein (MMR) expression in cancer cells and the density of TAIC were evaluated by immunohistochemistry in 89 SCNEC patients. The combined positive score (CPS), tumor proportion score (TPS), and immune cell score (ICS) of PD-L1 were measured, along with their correlation with clinicopathologic features in SCNEC patients using statistical analyses.ResultsCPS of PD-L1 ≥ 1 was seen in 68.5% of patients, positive TPS and ICS of PD-L1 were detected in 59.6% and 33.7% of patients, respectively. PD-L1CPS was higher in tumor-infiltrating immune cells (r = 0.387, p = 0.001) and positively correlated with programmed cell death-1 and forkhead box P3 + regulatory T cell (FOXP3 + Treg) infiltration (r = 0.443, p < 0.001; r = 0.532, p < 0.001). There was no statistical correlation between PD-L1 and MMR status. PD-L1CPS and PD-L1ICS positivity were independent prognostic factors, correlating with a favorable survival (HR (95%CI) = 0.363(0.139–0.950), p = 0.039 and HR (95% CI) = 0.199(0.050–0.802), p = 0.023, respectively). PD-L1ICS positivity was an independent indicator of recurrence in SCNEC patients and associated with better disease-free survival (HR (95% CI) = 0.124(0.036–0425), p = 0.001). TAIC and MMR levels had no statistical impact on survival results.ConclusionsPD-L1 positivity was seen in over half of SCNEC tumors. It may work synergistically with FOXP3 + Treg and other infiltrating immune cells to support an adaptive immune response. PD-L1 positivity may be a favorable prognostic factor in SCNEC.

The association between the tumor immune microenvironments and clinical outcome in low-grade, early-stage endometrial cancer patients.

Endometrial tumors show substantial heterogeneity in their immune microenvironment. This heterogeneity could be used to improve the accuracy of current outcome prediction tools. We assessed the immune microenvironment of 235 patients diagnosed with low-grade, early-stage endometrial cancer. Multiplex quantitative immunofluorescence was carried out to measure CD8, CD68, FOXP3, PD-1, and PD-L1 markers, as well as cytokeratin (CK), on tissue microarrays. Clustering results revealed five robust immune response patterns, each associated with specific immune populations, cell phenotypes, and cell spatial clustering. Most samples (69%) belonged to the immune-desert subtype, characterized by low immune cell densities. Tumor-infiltrating lymphocyte (TIL)-rich samples (4%) displayed high CD8+ T-cell infiltration, as well as a high percentage of CD8/PD-1+ cells. Immune-exclusion samples (19%) displayed the lowest CD8+ infiltration combined with high PD-L1 expression levels in CK+ tumor cells. In addition, they demonstrated high tumor cell spatial clustering as well as increased spatial proximity of CD8+ /PD-1+ and CK/PD-L1+ cells. FOXP3 and macrophage-rich phenotypes (3% and 4% of total samples) displayed relatively high levels of FOXP3+ regulatory T-cells and CD68+ macrophages, respectively. These phenotypes correlated with clinical outcomes, with immune-exclusion tumors showing an association with tumor relapse. When compared with prediction models built using routine pathological variables, models optimized with immune variables showed increased outcome prediction capacity (AUC = 0.89 versus 0.78) and stratification potential. The improved prediction capacity was independent of mismatch repair protein status and adjuvant radiotherapy treatment. Further, immunofluorescence results could be partially recapitulated using single-marker immunohistochemistry (IHC) performed on whole tissue sections. TIL-rich tumors demonstrated increased CD8+ T-cells by IHC, while immune-exclusion tumors displayed a lack of CD8+ T-cells and frequent expression of PD-L1 in tumor cells. Our results demonstrate the capability of the immune microenvironment to improve standard prediction tools in low-grade, early-stage endometrial carcinomas. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

CT-based radiomic nomogram for preoperative prediction of DNA mismatch repair deficiency in gastric cancer.

BackgroundDNA mismatch repair (MMR) deficiency has attracted considerable attention as a predictor of the immunotherapy efficacy of solid tumors, including gastric cancer. We aimed to develop and validate a computed tomography (CT)-based radiomic nomogram for the preoperative prediction of MMR deficiency in gastric cancer (GC).MethodsIn this retrospective analysis, 225 and 91 GC patients from two distinct hospital cohorts were included. Cohort 1 was randomly divided into a training cohort (n = 176) and an internal validation cohort (n = 76), whereas cohort 2 was considered an external validation cohort. Based on repeatable radiomic features, a radiomic signature was constructed using the least absolute shrinkage and selection operator (LASSO) regression analysis. We employed multivariable logistic regression analysis to build a radiomics-based model based on radiomic features and preoperative clinical characteristics. Furthermore, this prediction model was presented as a radiomic nomogram, which was evaluated in the training, internal validation, and external validation cohorts.ResultsThe radiomic signature composed of 15 robust features showed a significant association with MMR protein status in the training, internal validation, and external validation cohorts (both P-values <0.001). A radiomic nomogram incorporating a radiomic signature and two clinical characteristics (age and CT-reported N stage) represented good discrimination in the training cohort with an AUC of 0.902 (95% CI: 0.853–0.951), in the internal validation cohort with an AUC of 0.972 (95% CI: 0.945–1.000) and in the external validation cohort with an AUC of 0.891 (95% CI: 0.825–0.958).ConclusionThe CT-based radiomic nomogram showed good performance for preoperative prediction of MMR protein status in GC. Furthermore, this model was a noninvasive tool to predict MMR protein status and guide neoadjuvant therapy.

PRAME Expression in Endometrioid and Serous Endometrial Carcinoma: A Potential Immunotherapeutic Target and Possible Diagnostic Pitfall.

Preferentially expressed antigen in melanoma (PRAME) is a cancer testes antigen initially employed as a diagnostic marker for melanoma. Although negative in most normal tissues, its expression has been reported in benign endometrial glands. Additionally, PRAME expression has been identified in a growing list of solid and hematologic malignancies and is of interest as a predictive biomarker, as cancer vaccination strategies and adoptive T-cell transfer targeting this molecule are under clinical investigation; additionally, PRAME may identify candidates for retinoid therapy. However, expression of PRAME has not been well-studied in endometrial cancers. We herein evaluate PRAME expression in endometrial carcinomas to better characterize its limitations as a diagnostic melanoma marker as well as its potential as a predictive biomarker in endometrial carcinomas. PRAME expression was evaluated in 256 endometrioid (n=235) and serous (n=21) endometrial carcinomas via tissue microarray. In all, 89% (227/256) demonstrated some degree of nuclear PRAME expression, including 88% (207/235) of endometrioid carcinomas and 95% (20/21) of serous carcinomas. Diffuse (>50%) expression was observed in 70% (179/256) of all cases, including 69% (163/235) of endometrioid carcinomas and 76% (16/21) of serous carcinomas. There was no association between degree of expression and grade, mismatch repair protein status, or stage. The widespread expression of PRAME in endometrial carcinomas suggests this marker should not be interpreted as specific for melanoma in this context. However PRAME may have utility as a predictive biomarker in endometrial cancer, and expansion of testing of PRAME-based therapies to endometrioid and serous endometrial carcinomas may lead to new therapeutic options for these endometrial cancer subtypes.

Clinicopathologic significance of DNA mismatch repair protein status in endometrial cancer

ObjectiveThe prognostic implications of DNA mismatch repair protein (MMRP) have not been determined in endometrial cancer. Therefore, in this study, we aimed to evaluate the clinicopathologic characteristics of DNA MMRP deficiency in endometrial cancer. Materials and methodsWe examined the MMRP status of 206 patients with endometrial carcinomas, using immunohistochemistry, and analyzed their clinicopathologic factors and survival outcomes stratified by MMRP status using the Kaplan–Meier method and Cox regression analysis. ResultsForty-three cases were deficient for at least one MMRP (20.9%). Loss of MLH1 was the most common (13.1%), followed by MSH6 (7.8%). MMRP deficiency was significantly associated with lympho-vascular space invasion, deep myometrial invasion, and adjuvant treatment (P = 0.032, 0.041, and 0.047, respectively). MMRP-deficient patients had a better overall survival (OS), particularly at advanced cancer stages (III/IV) (100% vs. 73.7%, P = 0.170) or if they had received adjuvant treatment (100% vs. 86.7%, P = 0.087). ConclusionAlthough MMRP deficiency was associated with unfavorable prognostic risk factors in endometrial cancer, we found a trend in favor of OS in MMRP-deficient patients. More studies are needed to confirm its prognostic implication.