Clinicopathological and mutational analysis of esophageal basaloid squamous cell carcinoma

A comparative analysis of clinicopathological factors and survival between esophageal basaloid squamous cell carcinoma and conventional esophageal squamous cell carcinoma

INTRODUCTION

Recently, the number of diagnosed esophageal basaloid squamous cell carcinoma (EBSCC) has gradually increased. However, available data on EBSCC are limited to date.

METHODS

A total of 165 EBSCC (Cohort 1) and 515 conventional esophageal squamous cell carcinoma (ESCC) (Cohort 2) were retrospectively analyzed.

RESULTS

In Cohort 1, 70 cases only had invasive EBSCC component (42.4%, defined as Group 1), 73 cases had concomitant invasive ESCC component (44.2%, Group 2), and 22 had concomitant invasive poor-differentiated component (13.3%, Group 3). Lymph node metastasis rates of Group 3, Group 2 and Group 1 were ranked from high to low (P = 0.044). There were higher patient age (P = 0.047), smaller tumor size (P = 0.009), more nerve invasion (P < 0.001), and lower pTNM stage (P < 0.001) in EBSCC (Cohort 1), compared with ESCC (Cohort 2). In Cohort 1 and Cohort 2, pTNM stage was an independent prognostic factor for both DFS and OS. No significant survival difference was found between EBSCC (Cohort 1) and ESCC (Cohort 2) in pIA-B stage, pIIA-B stage, pIIIA-B stage and pIVA-B stage (P > 0.05).

CONCLUSION

Our analysis of the largest EBSCC series from a single institution to date with conventional ESCC demonstrated that EBSCC carried a similar prognosis with ESCC in pIA-B stage, pIIA-B stage, pIIIA-B stage and pIVA-B stage. And pure EBSCC, didn't have poorer survival than mixed EBSCC with concomitant ESCC or other components. Our findings may be valuable in the better understanding of EBSCC's biological behaviors, and the related molecular mechanism is needed to be explored in the future.

Molecular and clinicopathological analysis revealed an immuno-checkpoint inhibitor as a potential therapeutic target in a subset of high-grade myxofibrosarcoma

This study aimed to identify differences in genetic alterations between low- and high-grade lesions in myxofibrosarcoma (MFS) and to examine the efficacy of immune checkpoint inhibitors in 45 patients with MFS. First, genetic differences between low- and high-grade components within the same tumor were analyzed in 11 cases using next-generation sequencing. Based on the obtained data, Sanger sequencing was performed for TP53 mutations in the remaining 34 patients. Loss of heterozygosity (LOH) analysis was performed at the TP53 and RB1 loci. Immunohistochemistry was performed for FGFR3, KIT, MET, programmed death receptor ligand 1 (PD-L1), CD8, FOXP3, and mismatch repair proteins. The microsatellite instability status was also evaluated in all cases. TP53 deleterious mutations and LOH at TP53 and RB1 loci were detected significantly more frequently in high-grade than in low-grade MFS (P = 0.0423, 0.0455, and 0.0455, respectively). LOH at the RB1 locus was significantly associated with shorter recurrence-free survival in both univariate and multivariate analyses. TP53 alterations, such as mutation and LOH, were more frequently observed in low-grade areas within high-grade MFS than in pure low-grade MFS. The positive PD-L1 expression rate was 35.6% (16/45), and all these 16 cases were high-grade. A high density of both CD8+ and FOXP3+ tumor-infiltrating lymphocytes was associated with PD-L1 positivity. LOH at the RB1 locus was identified an independent adverse prognostic factor for recurrence-free survival in patients with MFS. Immune checkpoint inhibitors may be a therapeutic option for a subset of high-grade MFS.