Three novel rare TP53 fusion mutations in a patient with multiple primary cancers:a case report

As survival rates improve and detection technologies advance,the occurrence of multiple primary cancers(MPCs)has been increasing.Approximately 16%of cancer survivors develop a subsequent malignancy,with lung cancer often developing after esophageal cancer due to potential“field cancerization”effects.Despite this observation,the genetic heterogeneity underlying MPCs remains understudied.However,the recent emergence of genetic testing has expanded the scope of investigations into MPCs to investigate signatures underlying cancer predisposition.This report reveals 3 unprecedented TP53 fusion mutations in a Chinese patient afflicted by MPCs,namely,AP1M2–TP53(A1;T11)fusion,TP53–ILF3(T10;I13)fusion,and SLC44A2–TP53(S5;T11)fusion.This patient exhibited an extended period of survival after diagnosis of extensive-stage small cell lung cancer,which occurred 6 years after the diagnosis of esophageal squamous cell cancer.This unique reportmay provide supplementary data that enhance our understanding of the genetic landscape ofMPCs.

Mutational separation and clinical outcomes of TP53 and CDH1 in gastric cancer

BACKGROUND Gastric cancer(GC)is a deadly tumor with the fifth highest occurrence and highest global mortality rates.Owing to its heterogeneity,the underlying mechanism of GC remains unclear,and chemotherapy offers little benefit to individuals.AIM To investigate the clinical outcomes of TP53 and CDH1 mutations in GC.METHODS In this study,202 gastric adenocarcinoma tumor tissues and their corresponding normal tissues were collected.A total of 490 genes were identified using target capture.Through t-test and Wilcoxon rank-sum test,somatic mutations,microsatellite instability,and clinical statistics,including overall survival,were detected,compared,and calculated.RESULTS The mutation rates of 32 genes,including TP53,SPEN,FAT1,and CDH1 exceeded 10%.TP53 mutations had a slightly lower overall occurrence rate(33%).The TP53 mutation rate was significantly higher in advanced stages(stage Ⅲ/Ⅳ)than that in early stages(stage Ⅰ/Ⅱ)(P<0.05).In contrast,CDH1 mutations were significantly associated with diffuse GC.TP53 is related to poor prognosis of advanced-stage tumors;nevertheless,CDH1 corresponds to a diffuse type of cancer.TP53 is exclusively mutated in CDH1 and is primarily affected by two distinct GC mechanisms.CONCLUSION Different somatic mutation patterns in TP53 and CDH1 indicate two major mechanisms of GC.

Clinical spectrum and prognostic value of TP53 mutations in circulating tumor DNA from breast cancer patients in China

Background:TP53 mutations are common in breast cancer.There is currently no large-scale cohort study to investigate the TP53 landscape in breast cancer patients from China.The predictive value of TP53 mutations for the efficacy of human epidermal growth factor receptor 2(HER2)-targeted therapy in breast cancer remains controversial.In the present study,we aimed to analyze the clinical spectrum and prognostic value of TP53 mutations in circulating tumor DNA(ctDNA)from breast cancer patients in China.Methods:We retrospectively analyzed the clinical data and TP53 mutation features in ctDNA samples from 804 patients withmetastatic breast cancer.TP53 mutations were detected by target region capture-based next-generation sequencing.The relationship between TP53 mutation status and disease-free survival(DFS)was analyzed in 444 patientswithmetastatic breast cancer.Moreover,the relationship between TP53 mutation status and progression-free survival(PFS)was analyzed in 55 HER2-positive patients treated with first-line trastuzumab-based therapy.Kaplan-Meier analysis was performed to estimate the survival curves of the different subgroups,and the log-rank test was used to compare the curves.A Cox regression model was used to estimate multivariable-adjusted hazard ratios and their 95%confidence intervals(CIs)associated with the DFS and PFS.Results:Among the 804 investigated patients,431(53.6%)patients harbored TP53 mutations.TP53 mutations were differentially distributed among different molecular subtypes of breast cancer(P<0.05).Patients with TP53 mutations had a shorter DFS than those with wild-type TP53(hazard ratio=1.32,95%CI=1.09-1.61,P=0.005).TP53 mutations in exons 5-8 were associated with worse outcome(hazard ratio=1.50,95%CI=1.11-2.03,P=0.009).However,TP53 mutation status was not significantly associated with PFS in HER2-positive patients who received firstline trastuzumab-based therapy(P=0.966).Interestingly,in the taxane combination group,patients with TP53 mutations exhibited longer PFS than those without TP53 mutations(hazard ratio=0.08,95%CI=0.02-0.30,P<0.001).However,in the nontaxane combination group,patients with TP53 mutations displayed shorter PFS than those with wild-type TP53(hazard ratio=4.84,95%CI=1.60-14.66,P=0.005).Conclusions:TP53 mutations in exons 5-8 may be an independent prognostic marker for short DFS in patients with metastatic breast cancer.TP53 mutations had opposite effects on trastuzumab-treated patients treated with and without taxanes.

Transformation of marginal zone lymphoma into high-grade B-cell lymphoma expressing terminal deoxynucleotidyl transferase:A case report

BACKGROUND High-grade B-cell lymphoma(HGBL)is an unusual malignancy that includes myelocytomatosis viral oncogene(MYC),B-cell lymphoma-2(BCL-2),and/or BCL-6 rearrangements,termed double-hit or triple-hit lymphomas,and HGBL-not otherwise specific(HGBL-NOS),which are morphologically characteristic of HGBL but lack MYC,BCL-2,or BCL-6 rearrangements.HGBL is partially transformed by follicular lymphoma and other indolent lymphoma,with few cases of marginal zone lymphoma(MZL)transformation.HGBL often has a poor prognosis and intensive therapy is currently mainly advocated,but there is no good treatment for these patients who cannot tolerate chemotherapy.CASE SUMMARY We reported a case of MZL transformed into HGBL-NOS with TP53 mutation and terminal deoxynucleotidyl transferase expression.Gene analysis revealed the gene expression profile was identical in the pre-and post-transformed tissues,suggesting that the two diseases are homologous,not secondary tumors.The chemotherapy was ineffective and the side effect was severe,so we tried combination therapy including venetoclax and obinutuzumab.The patient tolerated treatment well,and reached partial response.The patient had recurrence of hepatocellular carcinoma and died of multifunctional organ failure.He survived for 12 months after diagnosis.CONCLUSION Venetoclax combined with obinutuzumab might improve the survival in some HGBL patients,who are unsuitable for chemotherapy.

Heterochronic triple primary malignancies with Epstein-Barr virus infection and tumor protein 53 gene mutation:A case report and review of literature

BACKGROUND The diagnosis and etiology of multiple primary malignant neoplasms(MPMNs)are difficult to establish.Here,we report a case of heterochronic triple primary malignancies with gastric cancer,nasopharyngeal squamous cell cancer,and then rectal cancer.CASE SUMMARY The patient was first diagnosed with gastric cancer at the age of 33 in 2014 and underwent distal gastrectomy and gastrojejunostomy and six cycles of adjuvant chemotherapy.Three years later,he was diagnosed with nasopharyngeal cancer and treated with radical chemoradiotherapy in 2017.Recently,a mass in the middle of the rectum was resected and reported as ulcerative,moderately to poorly differentiated adenocarcinoma.Research on the etiology of MPMNs showed that Epstein-Barr virus(EBV)infection may be the cause of gastric cancer and nasopharyngeal squamous cell cancer since these two primary lesions were positive for transcripts of EBV-encoded ribonucleic acid using an in situ hybridization EBV-encoded ribonucleic acid probe in formalin-fixed,paraffinembedded tissue.The cause of rectal cancer may be due to a somatic mutation of tumor protein 53 gene in exon 8(c.844C>T,p.Arg282Trp)through highthroughput sequencing for the rectal cancer.Appropriate standard therapy for each primary cancer was administered,and the patient has no evidence of cancer disease to date.CONCLUSION To our knowledge,this is the first report on heterochronic triple primary malignancies whose cause may be associated with EBV infection and tumor protein 53 genetic mutations.The etiological research may not only elucidate the cause of MPMN but also has implications in clinical management.

USH2A mutation and specific driver mutation subtypes are associated with clinical efficacy of immune checkpoint inhibitors in lung cancer

This study aimed to identify subtypes of genomic variants associated with the efficacy of immune checkpoint inhibitors(ICIs)by conducting systematic literature search in electronic databases up to May 31,2021.The main outcomes including overall survival(OS),progression-free survival(PFS),objective response rate(ORR),and durable clinical benefit(DCB)were correlated with tumor genomic features.A total of 1546 lung cancer patients with available genomic variation data were included from 14 studies.The Kirsten rat sarcoma viral oncogene homolog G12C(KRAS^(G12C))mutation combined with tumor protein P53(TP53)mutation revealed the promising efficacy of ICI therapy in these patients.Furthermore,patients with epidermal growth factor receptor(EGFR)classical activating mutations(including EGFRL858Rand EGFRΔ19)exhibited worse outcomes to ICIs in OS(adjusted hazard ratio(HR),1.40;95%confidence interval(CI),1.01-1.95;P=0.0411)and PFS(adjusted HR,1.98;95%CI,1.49-2.63;P<0.0001),while classical activating mutations with EGFR^(T790)Mshowed no difference compared to classical activating mutations without EGFR^(T790)Min OS(adjusted HR,0.96;95%CI,0.48-1.94;P=0.9157)or PFS(adjusted HR,0.72;95%CI,0.39-1.35;P=0.3050).Of note,for patients harboring the Usher syndrome type-2A(USH2A)missense mutation,correspondingly better outcomes were observed in OS(adjusted HR,0.52;95%CI,0.32-0.82;P=0.0077),PFS(adjusted HR,0.51;95%CI,0.38-0.69;P<0.0001),DCB(adjusted odds ratio(OR),4.74;95%CI,2.75-8.17;P<0.0001),and ORR(adjusted OR,3.45;95%CI,1.88-6.33;P<0.0001).Our findings indicated that,USH2A missense mutations and the KRAS^(G12C)mutation combined with TP53 mutation were associated with better efficacy and survival outcomes,but EGFR classical mutations irrespective of combination with EGFR^(T790)Mshowed the opposite role in the ICI therapy among lung cancer patients.Our findings might guide the selection of precise targets for effective immunotherapy in the clinic.