KRAS Mutations Research Articles

Using digital PCR to investigate the prevalence of KRAS variants in pituitary tumours.

Pituitary tumours (PT) are formed in the pituitary gland, a small gland situated at the base of the brain. These tumours can be categorized according to their histological origin and hormone production. In surgical series, non-functioning PT are the commonest subtype, followed by functioning somatotroph and corticotroph tumours. Different somatic alterations have been implicated in the pathogenesis of these tumours and the objective of our study was to expand our previous new finding of KRAS pathogenic genetic variants in pituitary tumours. We conducted a digital polymerase chain reaction (PCR) analysis on formalin-fixed paraffin-embedded tissue blocks belonging to 189 patients. The results showed that, from the 184 pituitary tumours with good quality samples, 13 tumours (7.1%) presented mutant KRAS. The median age of the mutated group was 47 years old (range 19-77) and most patients with mutant KRAS tumours were from the female gender (61.5%, 8/13) and non-functioning subtype. For the first-time, mutant KRAS in corticotroph and somatotroph tumours were detected, and the variants showed low allele frequencies. In conclusion, we demonstrated that pituitary tumours might have mutant KRAS, and these data were not previously described probably due to lack of sensitivity of previous technologies. By identifying these variants, even at minimal levels, we open doors to a deeper understanding of the tumour microenvironment, clonal evolution and potential therapeutic targets.

Analysis of the benefit of anti-PD-1 monotherapy according to NGS-diagnosed genetic alterations in patients with non-small cell lung cancer

Aim: Immune checkpoint inhibitors improved the survival of advanced non-small cell lung cancer. However, only 20% of patients respond to these treatments and the search for predictive biomarkers of response is still topical. The objective of this work is to analyze the anti-PD-1 monotherapy benefit based on genetic alterations diagnosed by next generation sequencing (NGS), in advanced non-small cell lung cancer. Methods: Patients with advanced non-small cell lung cancer treated with immunotherapy were retrospectively included in this monocentric study. Clinical data, immunohistochemical expression of PD-L1 and molecular data, with a 22-genes NGS panel, were collected. Results: 107 patients were included. The median age was 65 years [59; 73], 70 were men (65%), 96 had adenocarcinoma (90%), 33 were receiving a first line (31%). 54 patients had KRAS mutation (50%) and 56 had TP53 mutation (52%). The remaining mutations were present in fewer than 10 patients. There was no statistically significant differences in median of progression-free or overall survival based on KRAS-only, TP53-only or KRAS-TP53 mutations co-mutated compared to double wild-type patients (P = 0.46 and P = 0.72 respectively). Conclusions: The search for a predictive composite biomarker remains a major issue in the coming years.

Comparison of targeted next generation sequencing assays in non-small cell lung cancer patients

Non-small cell lung cancer (NSCLC) is the most prevalent type of lung cancer the mutational spectrum of which has been extensively characterized. Treatment of patients with NSCLC based on their molecular profile is now part of the standard clinical care. The aim of this study was firstly to investigate two different NGS-based tumor profile genetic tests and secondly to assess the clinical actionability of the mutations and their association with survival and clinicopathological characteristics. Overall, 52 mutations were identified in 31 patients by either one or both assays. The most frequently mutated genes were TP53 (40.4%), KRAS (13.46%) and EGFR (9.62%). TP53 and KRAS mutations were associated with worst overall survival while KRAS was positively correlated with adenocarcinoma. The two methods showed a high concordance for the commonly covered genomic regions (97.14%). Ten mutations were identified in a genomic region exclusively covered by the MEDICOVER Genetics custom tumor profile assay. Likewise, one MET mutation was identified by the Ion Amliseq assay in a genomic region exclusively covered by Ion Amliseq. In conclusion both assays showed highly similar results in the commonly covered genomic areas, however, the MEDICOVER Genetics assay identified additional clinically actionable mutations that can be applied in clinical practice for personalized treatment decision making for patients with NSCLC.

Adequacy of EUS–guided fine-needle aspiration and fine-needle biopsy for next-generation sequencing in pancreatic malignancies: A systematic review and meta-analysis

ABSTRACT Background and Objectives A majority of pancreatic malignancies are unresectable at the time of presentation and require EUS–guided fine-needle aspiration or fine-needle biopsy (EUS-FNA/FNB) for diagnosis. With the advent of precision therapy, there is an increasing need to use EUS-FNA/FNB sample for genetic analysis. Next-generation sequencing (NGS) is a preferred technology to detect genetic mutations with high sensitivity in small specimens. We performed a meta-analysis to evaluate the adequacy of EUS-FNA/FNB for NGS in pancreatic malignancies. Methods PubMed, Embase, Cochrane Library, and Web of Science were searched from database inception to November 11, 2023. The primary outcome was the proportion of sufficient sample acquired by EUS-FNA/FNB in pancreatic malignancies for NGS. Secondary outcomes were the proportion of sufficient sample for NGS in pancreatic ductal adenocarcinoma (PDAC) and the detection rates of mutations in KRAS, TP53, CDKN2A, and SMAD4 and actionable mutations in PDAC. The pooled proportions were calculated using a random-effects model. Potential sources of heterogeneity were investigated with subgroup analyses and meta-regression. Results Twenty studies with 881 samples were included. The pooled adequacy of EUS-FNA/FNB sample for NGS was 89.9% (95% CI, 80.8%–96.7%) in pancreatic malignancies and 92.0% (95% CI, 81.3%–98.8%) in PDAC. Screening sample suitability before NGS testing was associated with lower adequacy in subgroup analysis (79.7% vs. 98.4%, P = 0.001). The pooled prevalences of mutations in KRAS, TP53, CDKN2A, and SMAD4 in PDAC were 87.4% (95% CI, 83.2%–91.2%), 62.6% (95% CI, 53.2%–71.7%), 20.6% (95% CI, 11.9%–30.8%), and 19.4% (95% CI, 11.2%–29.1%), respectively. The pooled prevalence of potentially actionable mutations in PDAC was 14.5% (95% CI, 8.2%–22.0%). Conclusions In the majority of cases, EUS-FNA/FNB can acquire adequate sample for NGS and identify tumor-specific mutations in patients with pancreatic malignancies. Strict pre-analysis screening criteria may negatively impact the sample adequacy and the success rate for NGS.

Signet-ring cell carcinoma of the transverse colon in a 10-year-old girl: A case report

BACKGROUND Signet-ring cell carcinoma (SRCC) is a rare subtype of colorectal cancer. The incidence of primary colonic SRCC is relatively rare in pediatric patients, with a limited number of reported cases currently available. The prognosis for this specific tumor type is unfavorable, and the preoperative diagnosis presents challenges, potentially leading to misdiagnosis. This case report describes the diagnosis of primary SRCC in the colon of a 10-year-old girl. CASE SUMMARY The patient was admitted to the hospital due to abdominal pain and vomiting. A computed tomography scan revealed an irregular mass with soft tissue density in her transverse colon, showing uneven density and multiple calcifications. The patient underwent surgical resection of the affected bowel and lymph node dissection, which was confirmed by pathological examination to be SRCC infiltrating both nerves and the entire intestinal wall. Additionally, tumor thrombus formation was observed in blood vessels and lymphatic vessels, multiple cancerous nodules were found in the omentum, and metastasis to 18 of 26 mesenteric lymph nodes examined. Immunohistochemistry for mismatch repair gene protein demonstrated microsatellite stability. No mutations in KRAS , NRAS , BRAF , or PIK3CA genes were detected through molecular pathology analysis. After surgery, she received standard chemotherapy for 8 cycles without tumor progression or other abnormalities during a 12-month follow-up period. CONCLUSION Primary colonic SRCC is a rare malignant tumor with atypical clinical symptoms, and timely identification and intervention are crucial for improving the prognosis.

Mixed pancreatic ductal adenocarcinoma and well-differentiated neuroendocrine tumor: A case report

BACKGROUND Pancreatic mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are rare malignancies affecting the pancreas. The World Health Organization defines MiNENs as neoplasms composed of morphologically recognizable neuroendocrine and non-neuroendocrine components, each constituting 30% or more of the tumor volume. Adenocarcinoma-neuroendocrine carcinoma is the most frequent MiNEN combination. A well-differentiated neuroendocrine tumor (NET) component is rarely reported in MiNENs. CASE SUMMARY Here we report a rare case with intermingled components of ductal adenocarcinoma and grade 1 well-differentiated NET in the pancreas. The two tumors show distinct histology and significant differentiation discrepancy (poorly differentiated high grade adenocarcinoma and well-differentiated low grade NET), and also present as metastases in separate lymph nodes. Next generation sequencing of the two components demonstrates KRAS and TP53 mutations in the ductal adenocarcinoma, but no genetic alterations in the NET, suggesting divergent origins for these two components. Although tumors like this meet the diagnostic criteria for MiNEN, clinicians often find the diagnosis and staging confusing and impractical for clinical management. CONCLUSION Mixed NET/non-NET tumors with distinct histology and molecular profiles might be better classified as collision tumors rather than MiNENs.

BIOACTIVE COMPOUNDS OF Moringa oleifera AS KRASG12C INHIBITORS IN COLORECTAL CANCER: IN SILICO STUDY

KRAS is a GTPase enzyme that regulates cell growth and division. Mutations in KRAS can lead to its permanent activation, resulting in uncontrolled cell growth and cancer progression. Approximately 30–44% of colorectal cancer cases harbor KRAS mutations, with 1–3% involving the KRASG12C variant. Historically considered "undruggable," recent advancements, such as Sotorasib, have demonstrated the potential to target KRASG12C effectively, making it a promising focus for drug discovery. Moringa oleifera, a plant rich in phytochemicals, is a potential source of bioactive compounds with therapeutic applications. In this study, 218 compounds derived from M. oleifera were screened using molecular docking, targeting KRASG12C. Quercetin (3) exhibited the lowest binding affinity (-9.37 kcal/mol) and showed interactions with key residues, including GLN100A, VAL104A, LYS17A, and TYR97A, suggesting a binding mechanism similar to that of Sotorasib as native ligand. The physicochemical analysis further revealed high gastrointestinal absorption, good lipophilicity, and favorable bioavailability scores for Quercetin (3), supporting its potential as a drug candidate. These findings highlight the potential of M. oleifera compounds, particularly quercetin (3), as inhibitors of KRASG12C in colorectal cancer.

Phase 1/2 trial of XPO1 inhibitor selinexor plus docetaxel in previously treated, advanced KRAS mutant non-small cell lung cancer.

Patients with KRAS mutant non-small cell lung cancer (NSCLC) have limited therapeutic options. Based on activity of nuclear export inhibition in preclinical models, we evaluated this strategy in previously treated advanced KRAS mutant NSCLC. The primary outcome of this multi-center phase 1/2 dose escalation trial of selinexor plus docetaxel was safety and tolerability. Selinexor was started one week before docetaxel to permit monotherapy pharmacodynamic assessment. Among 40 enrolled patients, median age was 66 years, 55% were female, and 85% were white. Maximum tolerated dose was selinexor 60 mg orally weekly plus docetaxel 75 mg/m2 every three weeks. The most common adverse events were nausea (73%, 8% Gr ≥3), fatigue (70%, 5% Gr ≥3), neutropenia (65%, 60% Gr ≥3), and diarrhea (58%, 10% Gr ≥3). Of 32 efficacy evaluable patients, 7 (22%) had partial responses and 18 (56%) had stable disease. Outcomes were not associated with KRAS mutation type but were significantly better in cases with wild type TP53 (42%), including disease control and response rates (27% and 80%, vs. 9% and 27%, respectively; P=0.03) and progression-free survival (median 7.4 vs. 1.8 months; HR, 0.2; 95% CI, 0.07-0.67; P=0.003). Post-selinexor / pre-docetaxel, serum LDH levels increased an average 51 U/L in TP53 altered and decreased an average 48 U/L in TP53 wild type cases (P=0.06). Selinexor plus docetaxel was relatively well tolerated in patients with advanced KRAS mutant NSCLC. The regimen has promising efficacy in TP53 wild type cases, where selinexor monotherapy may also have activity.

Primary retroperitoneal mucinous cystic tumor with borderline malignancy, microinvasion, and KRAS mutation: A case report

Introduction: Primary retroperitoneal mucinous cystic tumors with borderline malignancy are rare neoplasms of uncertain histopathogenesis with few cases reported in the literature. Histologically, these tumors are an analogous counterpart to the more common ovarian mucinous borderline tumor. A microinvasive component of these neoplasms may contribute to higher probabilities of recurrence and poor prognosis, while the presence of various mutations, particularly in KRAS and GNAS exons, could have therapeutic relevance in the future. Case Report: Imaging studies of a 42-year-old female with abdominal pain and distension revealed a large abdominopelvic cystic tumor. This tumor was initially misdiagnosed as adnexal. Gynecologic surgery showed the tumor to depend on the retroperitoneum. The patient had intact gynecologic organs. Further, a macroscopic study revealed a cystic cavity filled with serous liquid, with dominant papillary excrescence, and multiple microscopic papillae distributed along the inner lining. Moreover, a histologic analysis showed a proliferation of more than 10% of cylindrical mucosecretory epithelium, with dysplasia and focal infiltration to the stroma. Additionally, the immunohistochemistry revealed diffuse epithelial positivity for CK7 and focal CK20 positivity. Superior and inferior gastrointestinal endoscopies were done, where the possibility of a neoplastic origin in here was ruled out. Next-generation sequencing showed a missense mutation in exon 2 of KRAS. Conclusion: While the histopathogenesis of primary retroperitoneal mucinous tumors remains uncertain, the overall behavior and prognosis is remarkably similar to their better-known mucinous counterparts in the ovary. The possibility of targeted treatments in cases with malignancy, recurrence, and metastases also remains an important topic in molecular oncology, highlighting the need for further molecular profiling.

Advancements in Targeted Therapies Based on the EGFR, and KRAS Genetic Mutations in Lung Cancer

Non-small cell lung cancer (NSCLC), a type of lung cancer, has long been one of the leading causes of cancer-related deaths globally. Advances in understanding the genetic mutations associated with NSCLC, such as EGFR, and KRAS mutations, have led to significant progress in developing treatments tailored to them. However, despite these developments, challenges like drug resistance and variability in patient-specific responses still persist. This paper delves into the current research on genetic mutations in NSCLC, and the effectiveness of related treatments, focusing on the EGFR and KRAS gene mutations. While treatments have improved patient outcomes, they are often limited by various factors such as the development of resistance and off-target effects. This research highlights the importance of personalized treatments and emerging therapies, such as advanced drug delivery systems and new immunotherapies in overcoming these pre-existing limitations. The findings provide insight for future research and the need for continued innovation in treatments. The current unresolved issues such as patient-specific responses, secondary mutations, and the off-target effects suggest that developments in the near future might need to focus on enhancing personalization, the cost, and mechanisms regarding overcoming resistance.

"Undruggable KRAS": druggable after all.

The three RAS genes (HRAS, KRAS, and NRAS) comprise the most frequently mutated oncogene family in cancer. KRAS is the predominant isoform mutated in cancer and is most prevalently mutated in major causes of cancer deaths including lung, colorectal, and pancreatic cancers. Despite extensive academic and industry efforts to target KRAS, it would take nearly four decades before approval of the first clinically effective KRAS inhibitors for the treatment of KRAS mutant lung cancer. We revisit past anti-KRAS strategies and painful lessons learned and then focus on the rapidly evolving landscape of direct RAS inhibitors, resistance mechanisms, and potential combination treatments.

First Insight into the Mutational Landscape of BRAF and KRAS Genes in Lung Cancer Patients from Morocco

Background: Lung cancer (LC) is a lethal malignancy with a late diagnosis and poor prognosis. During the last decade, the identification of oncogenic driver alterations has noticeably changed the therapeutic landscape and contributed to the emergence of the “oncogene addiction” concept and precision medicine in oncology. Among these alterations, the spotlight has turned to driver mutations in the KRAS and BRAF genes, which have garnered significant attention due to the emergence of targeted therapies and the potential for personalized treatment strategies. Objective: Hence, the present study aimed to evaluate the mutational landscape of the KRAS and BRAF genes in LC Moroccan patients along with their frequencies and their correlation with clinicopathological features. Methods: A total of 60 fresh biopsies were collected from patients with primary LC and were subjected to PCR-DNA sequencing of exon 2 of KRAS and exon 15 of BRAF genes in order to detect the most common mutations known by their implication in response to targeted therapies. Results: Sequencing analysis revealed that mutations in KRAS and BRAF genes represented respectively 8.3% and 6.7% of cases; one patient had two KRAS mutations (G12A and K5E), and none had simultaneous BRAF and KRAS mutations. The vast majority of patients harboring KRAS mutations were men, formal smokers with adenocarcinomas, and at advanced stage (stage III). BRAF mutations were mainly detected in men and nonsmokers with adenocarcinoma. Statistical analyses showed no significant correlation between KRAS and BRAF substitutions and clinico-pathological features (p>0.05). Conclusion: The presence of these mutations will be used as a valuable molecular biomarker to select potential candidates eligible for effective personalized medicine using available agents targeting these mutations. Much effort is needed to identify other druggable mutations to generalize personalized LC therapy for better management of this devastating disease.

Prognostic and Molecular Characterization of Metastatic Transverse Colon Cancer: Insights From a Single-Center Retrospective Study.

Metastatic transverse colon cancer (TCC) represents a unique subset of colorectal cancer with features of both right and left colon tumors due to its distinct embryologic origin. This study retrospectively analyzes the clinical, pathological, and molecular factors influencing survival outcomes in TCC patients treated at a single center. For this study, we reviewed the files of 372 metastatic patients and analyzed the data of 71 patients with a diagnosis of TCC in detail. The remaining patients were patients with right or left colon tumors and we compared the overall survival (OS), molecular mutations (KRAS, NRAS, BRAF, MSI status), and clinicopathological features of our patients with transverse colon tumors with these patients. The median OS for TCC patients was 19.7 months, with metastasectomy and Eastern Cooperative Oncology Group (ECOG) performance status emerging as significant prognostic factors. Molecular analyses revealed KRAS mutations in 49% and BRAF mutations in 13% of TCC cases, aligning TCC closer to right-sided tumors in certain molecular characteristics. However, histopathologic diversity, including mucinous histology in 20% of TCC cases, indicated a need to consider TCC as a distinct entity. These findings underscore the complex biological nature of TCC and the necessity for tailored therapeutic approaches, especially as survival rates remain suboptimal. Further multicenter, prospective studies are recommended to establish refined treatment strategies for TCC patients.

Epidermal Growth Factor Receptor (EGFR) and SMAD4 negatively correlated in the progression of gallbladder cancer in Eastern Indian patients

Background and introductionTwo and half percent of the Indian population suffer from gallbladder cancer (GBC). The primary factors that lead GBC are associated with mutation of several protooncogenes such as EGFR, ERBB2, Myc, and CCND1 along with dysregulation of several tumor suppressor genes such as SMAD4 and CDKN2A. Bacterial infection caused by S.typhi and H.pylori are also hypothesized to be potential factors driving GBC.AimsThis study aims to investigate the molecular mechanisms driving the progression of gallbladder adenocarcinoma in Eastern Indian patients. We specifically focussed on analyzing the mutational status of the KRAS gene, examining the amplification of the ERBB2/Her2-neu gene, and evaluating the expression patterns of six dysregulated genes (CCND1, MYC, EGFR, ERBB2/Her2-neu, CDKN2A, SMAD4). Additionally, we assessed the expression status of TGF-beta, the association between bacterial infections (S. Typhi and H. pylori) and GBC, and the impact of single nucleotide polymorphisms in ERBB2/Her2-neu and CCND1 genes within this population.MethodsSixty-seven samples from GBC-diagnosed patients, 26 other unrelated GBC samples for validation cohort, and 68 gallstone tissue samples were collected for this study. Genomic DNA from normal as well as tumor tissues were isolated, exon 2 and exon 3 of KRAS gene were amplified along, DNA sequenced and analyzed. KRAS codon 12 mutation was detected by allele specific PCR (ASPCR) method. Amplification of UreC A (coding for urease subunit α), VacA (coding for Vacuolating cytotoxin A) and CagA genes (coding for cytotoxin-associated gene A) in H.pylori were amplified using PCR. Similarly, FlicC (coding for flagellin gene C) in S.typhi was amplified using PCR. The ERBB2/Her2-neu SNP I655V, and CCND1 SNP A870G were analyzed using PCR followed by RFLP. Expression studies of CCND1, Myc, CDKN2A, ERBB2/Her2-neu, EGFR, and SMAD4 genes were measured in GBC tumor tissues by sybr green quantitative RT PCR.ResultsThe oncogenes (EGFR and ERBB2/Her2-neu) were statistically significantly overexpressed and the tumor suppressor gene (SMAD4) downregulated in our GBC tumor patient samples. The EGFR and SMAD4 genes were negatively correlated (r = -0.01) in GBC patients and the data is statistically significant and validated through IHC technique. A significant downregulation of TGF-beta had also been observed. Lower frequency (i.e. 11.5%) of KRAS mutation in GBC tumor was observed.ConclusionsEGFR and SMAD4 expression were found to be negatively correlated in GBC tissue samples. ERBB2 overexpression/amplification was observed in 30% of the GBC samples. We also found a low percentage of GBC samples to show KRAS codon 12 mutation in Indian GBC patient population, as had been previously documented in pancreatic cancers.

KRAS Variants Are Associated With Survival Outcomes and Genomic Alterations in Biliary Tract Cancers.

KRAS variants are associated with poor outcomes in biliary tract cancers (BTCs). This study assesses the prevalence of KRAS variants and their association with survival and recurrence in patients with intrahepatic cholangiocarcinoma (IHC), extrahepatic cholangiocarcinoma (EHC), and gallbladder adenocarcinoma (GB). In this cross-sectional, single-institution study at Memorial Sloan Kettering, tumors from 985 patients treated between 2004 and 2022 with IHC, EHC, and GB who underwent either curative-intent resection or were treated with chemotherapy for unresectable disease were used for targeted sequencing. Of the 985 patients sequenced, 15% had a KRAS mutation. Five hundred and seventy-two had unresectable disease (n = 395 IHC, n = 71 EHC, n = 106 GB) and 413 were treated with curative-intent resection (n = 175 IHC, n = 119 EHC, and n = 119 GB). Median follow-up time was 18 months (IQR, 11-31). KRAS G12D mutations were most common in IHC (38%) and EHC (37%) tumors. Mutations in SF3B1 co-occurred with mutant KRAS in IHC and EHC, with comutant resectable patients having worse survival after adjusting for tumor type (hazard ratio [HR], 4.04 [95% CI, 1.45 to 11.2]; P = .007). KRAS G12 mutations were associated with worse survival in patients with IHC compared with wild-type (WT) or other KRAS mutations, regardless of resection status (unresectable P < .001, resectable P = .011). After adjusting for clinical covariates, KRAS G12 mutations remained a prognostic indicator for patients with IHC compared with WT (HR, 1.99 [95% CI, 1.41 to 2.80]; P < .001). The adverse impact of KRAS mutations in BTC is driven by G12 alterations in patients with IHC regardless of resection status, which was not observed in GB or EHC. There are unique comutational partners in distinct BTC subsets. These differences have important clinical implications in the era of KRAS-targeted therapeutics.

Lung adenocarcinomas with mucinous histology: clinical, genomic, and immune microenvironment characterization and outcomes to immunotherapy-based treatments and KRASG12C inhibitors

BackgroundApproximately 10% of lung adenocarcinomas (LUAD) have mucinous histology (LUADMuc), which is associated to a light/absent smoking history and a high prevalence of KRAS mutations. We sought to characterize LUADMuc by comparing it to LUAD without mucinous histology (LUADnon-muc) and determine the relative benefit of current treatments. Patients and MethodsPatients with LUAD from five institutions and TCGA PanCancer Atlas classified as LUADMuc or LUADnon-muc were included. Clinicopathologic, genomic, immunophenotypic, transcriptional features, and treatment outcomes were compared between LUADMuc and LUADnon-muc. ResultsOf 4,082 patients with LUAD, 9.9% had LUADMuc. Compared to LUADnon-muc, patients with LUADMuc had a lighter smoking history (median: 15 vs 20 pack-years, P=0.008), lower PD-L1 TPS (median: 0% vs 5%, P<0.0001), and lower tumor mutation burden (median: 6.8 vs 8.5 mutations/megabase, P<0.0001). Mutations in KRAS, NKX2-1 (TTF-1), STK11, SMARCA4, GNAS, and ALK rearrangements were enriched in LUADMuc, while TP53, EGFR, BRAF, and MET mutations were enriched in LUADnon-muc. At stage IV diagnosis, LUADMuc was more likely to have contralateral lung metastasis (55.2% vs 36.9%, P<0.0001) and less likely to have brain metastases (23.3% vs 41.9%, P<0.0001). Compared to LUADnon-muc, LUADMuc cases showed lower intratumor CD8+, PD-1+, CD8+PD-1+, and FOXP3+ cells. Among metastatic cases receiving ICIs, compared to LUADnon-muc (N=1,511), LUADMuc (N=112) had lower objective response rate (ORR, 8.4% vs 25.9%, P<0.0001), and shorter median progression-free survival (mPFS, 2.6 vs 3.9 months, P<0.0001) and overall survival (mOS, 9.9 vs 17.2 months, P<0.0001). Similarly, patients with LUADMuc had worse outcomes to chemo-immunotherapy. LUADMuc (N=18) and LUADnon-muc (N=150) had similar ORR (16.7% vs 34.9%, P=0.12) and mPFS (4.6 vs 5.6 months, P=0.17) to treatment with KRASG12C inhibitors, but LUADMuc had shorter mOS (6.8 vs 10.8 months, P=0.018). ConclusionLUADMuc represents a distinct LUAD subpopulation with unique clinicopathologic, genomic, immunophenotypic, and transcriptional features, achieving worse outcomes to standard immunotherapy-based treatments.

Analysis of Methylation of Tumor-suppressive miRNAs and KRAS/TP53 Mutations in Pancreatic Juice.

We previously reported the usefulness of detecting aberrant methylation in tumor suppressive microRNAs (miRNAs) in bile and plasma to discriminate pancreaticobiliary cancers from benign pancreaticobiliary diseases. This study analyzed the methylation of miRNAs in pancreatic juice to identify those specific to pancreatic cancer (PC). Pancreatic juice was collected from 20 patients with PC, including eight with intraductal papillary mucinous carcinoma (IPMC), two with low grade-pancreatic intraepithelial neoplasia (LG-PanIN), 32 with LG-intraductal papillary mucinous neoplasm (IPMN), and seven with benign pancreatic lesions. Polymerase chain reaction amplification and sequencing were performed for three tumor suppressive miRNAs (miR-200a, 200b, and 1247), and their methylation rates were determined. Additionally, KRAS and TP53 mutations were analyzed. The methylation rate of miR-1247 was significantly higher in patients with PC than in those with LG-PanIN/IPMN. Furthermore, it was significantly higher in patients with IPMC than in those with LG-IPMN. KRAS and TP53 mutations were detected in seven (70%) and one (10%) of the patients with PC, respectively. Analyzing the methylation of miR-1247 in addition to KRAS and TP53 mutations in pancreatic juice may be useful to distinguish PC from PanIN/IPMN.

INDEPSO-ISPSM Consensus on Peritoneal Malignancies: Management of Colorectal Peritoneal Metastases.

This manuscript reports the results of the Indian Network for Development of Peritoneal Surface Oncology and Indian Society of Peritoneal Surface Malignancies (INDEPSO-ISPSM) consensus that aimed to provide recommendations for some important aspects management of patients with colorectal peritoneal metastases (CPM) and address some issues unique to India. The modified Delphi technique was used with two rounds of voting. There were 29 questions on nine main topics-the role of cytoreductive surgery (CRS), patient selection for CRS, preoperative workup, role of systemic chemotherapy (SC), CPM with other visceral metastases, molecular profile, hyperthermic intraperitoneal chemotherapy (HIPEC) and other modalities of intraperitoneal chemotherapy (IPC), prophylactic/preventive strategies, and surveillances after CRS. A consensus was achieved if anyone option received >70 votes (strong consensus >90%). Forty-eight surgical (n = 41) and gastrointestinal (n = 7) oncologists were invited; 44 agreed to participate. The response rate was 95.4% (42/44) in round 1 and 93.1% (41/44) in round 2. Overall, a consensus was achieved on 23/29 (79.3%) questions (strong consensus on 6/29 [20.6%]). The panel strongly recommended considering surgery for limited CPM with limited liver metastases (92.5%), not altering the surgical approach in patients with KRAS mutations (91.67%), and limiting the use of IPC for unresectable CPM outside clinical trials (95%). Adjuvant SC was recommended for all patients undergoing CRS (89.47%). CRS is a therapeutic option for selected patients with CPM including those with metachronous CPM (79.49) and signet ring cell cancers (76.92%). HIPEC was recommended outside clinical trials only for patients with peritoneal cancer index 11-15(80%). The panel recommended CRS for most indications but was very selective in recommending HIPEC and IPC outside clinical trials. These recommendations should be a useful resource in clinical decision making for clinicians treating CPM in India and regions with a similar sociodemographic background.

Liquid Biopsy for Evaluating Mutations and Chromosomal Aberrations in Cerebrospinal Fluid from Patients with Primary or Metastatic Central Tumors

BackgroundCytopathology analysis of cerebrospinal fluid (CSF) is limited in detecting tumors in patients with suspected primary or metastatic central nervous system (CNS) malignancy. We investigated the use of CSF liquid biopsy (LBx) to detect neoplastic processes in the CNS. Methods: Cell-free DNA (cfDNA) from the CSF of patients with suspected metastatic (N=106) or primary CNS (N=23) tumors was deep sequenced using a 302-gene panel. ResultsFour samples (3%) (3 metastatic and 1 primary) failed sequencing quality control criteria. Metastatic tumor was confirmed in 84 (82%) of the 103 patients suspected of metastatic tumor. Primary CNS tumor was confirmed in 11 of 22 (50%) patients suspected of CNS tumor. Chromosomal abnormalities were detected in 55 samples (54%). Germline mutations were detected in 23 (22%) patients with metastatic tumors and in 1 (5%) with a primary CNS tumor. Of the 29 patients with metastatic breast cancers, 2 (7%) had mutations in ESR1 and 9 (31%) had mutations in PIK3CA. Of the 21 patients with metastatic lung cancer, 9 (43%) had EGFR mutations and 5 (24%) had KRAS mutations. Upon comparing CSF LBx with peripheral blood LBx in 14 patients, 13 (93%) showed only CHIP and one patient showed CNS primary tumor mutation. Serial samples from 14 patients demonstrate that CSF LBx can be used for monitoring therapy efficacy. ConclusionsLBx using CSF is clinically reliable and provides informative results in a substantial proportion of patients with metastatic CNS tumors and to a lesser degree in patients with primary CNS tumors.

Investigating the pathogenicity of uncommon KRAS mutations and their association with clinicopathological characteristics in patients with colorectal cancer.

Kirsten rat sarcoma viral oncogene homolog (KRAS) somatic mutations occur in 30-40% of colorectal cancer (CRC) patients. These were thought to equally affect prognosis and resistance to anti-EGFR agents. However, recent data show the activity of KRAS-G12C and Pan-RAS inhibitors. The effects of uncommon KRAS (uKRAS) variants are largely unexplored. The distribution and pathogenicity of uKRAS mutations and their relationship with patients' clinico-pathological features were assessed. 2427 CRCs were profiled for KRAS using next-generation sequencing (NGS). The study and control groups included patients with uKRAS (<1% frequency in CRC datasets on cBioPortal) and canonical KRAS (cKRAS) mutations, respectively. In silico protein structure modifications and prediction analyses were performed using PyMol, trRosetta, and PolyPhen-2. uKRAS mutations affected 35 cases (1.5%), with G13C (28.6%), G12R (20%), and V14I (8.6%) being most common. Missense mutations (D33E, G12W, G12F, Q22H, Q61L, and L19F) occurred in 9 cases (25.7%). Duplications (G10dup and L52_G60dup) affected 2 cases. Pathogenicity analyses showed that G12W, Q22R, L56V, and A130I mutations are probably damaging with scores between 0.928 and 1.000. No differences were seen in clinicopathological features. uKRAS mutants had lower event-free survival but no difference in overall survival compared with controls. This data is hypothesis-generating and needs further confirmation; however, they highlight the importance of NGS-based profiling to identify CRC patients with uKRAS mutations as candidates for personalized therapy.