Rare tumors of esophageal squamous mucosa

Integrated molecular characterization of esophageal basaloid squamous cell carcinoma: a subtype with distinct RNA expression pattern and immune characteristics, but no specific genetic mutations

Esophageal basaloid squamous cell carcinoma (bSCC) is a subtype of squamous cell carcinoma (SCC) with a different behavior and poor prognosis. Exploring bSCC's molecular characteristics and treatment strategies are of great clinical significance. We performed multi-omics analysis of paired bSCC and common SCC (cSCC) using whole exome sequencing and a NanoString nCounter gene expression panel. Immunohistochemistry was used for verification of candidate biomarkers. Different treatment response was analyzed on both patients receiving neoadjuvant treatment and late-stage patients. The common genetically-clonal origin of bSCC and cSCC was confirmed. No significant differences between their genetic alterations or mutation spectra were observed. Mutation signature 15 (associated with defective DNA damage repair) was less prominent, and tumor mutational burden (TMB) was lower in bSCC. bSCC with an RNA expression pattern resembling cSCC had a better survival than other bSCCs. Moreover, bSCC showed significant upregulation of expression of genes associated with angiogenesis response, basement membranes, and epithelial-mesenchymal transition, and downregulation of KRT14 (squamous differentiation) and CCL21 (associated with immune response). Immunohistochemistry for SFRP1 was shown to be highly sensitive and specific for bSCC diagnosis (p < 0.001). In addition, bSCC receiving neoadjuvant immuno-chemotherapy had a worse pathological response than bSCC receiving neoadjuvant chemotherapy (but without statistical significance), even in bSCC positive for PD-L1. Our results demonstrated the molecular characteristics of esophageal bSCC as a subtype with a distinct RNA expression pattern and immune characteristics, but no specific genetic mutations. We provided a useful biomarker, SFRP1, for diagnosis. After outcome analysis for six bSCCs with neoadjuvant immunotherapy treatment and four late-stage bSCCs with immunotherapy, we found that immunotherapy may not be an effective treatment option for most bSCCs. This may also provide a clue for the same subtypes of lung and head and neck cancer. Our study highlighted the heterogeneity among bSCC patients, and might explain the conflicting results of bSCC outcomes in existing studies. © 2022 The Pathological Society of Great Britain and Ireland.

Neoplastic and pre-neoplastic lesions of the oesophagus and gastro-oesophageal junction

Oesophageal and gastro-oesophageal junction (GOJ) neoplasms, and their predisposing conditions, may be encountered by the practicing pathologist both as biopsy samples and as surgical specimens in daily practice. Changes in incidence of oesophageal squamous cell carcinomas (such as a decrease in western countries) and in oesophageal and GOJ adenocarcinomas (such as a sharp increase in western countries) are being reported globally. New modes of treatment have changed our histologic reports as specific aspects must be detailed such as in post endoscopic resections or with regards to post neo-adjuvant therapy tumour regression grades. The main aim of this overview is therefore to provide an up-to-date, easily available and clear diagnostic approach to neoplastic and pre-neoplastic conditions of the oesophagus and GOJ, based on the most recent available guidelines and literature.

Comparative Analysis of Clinicopathological Characteristics, Survival Features, and Protein Expression Between Basaloid and Squamous Cell Carcinoma of the Esophagus

Background

Basaloid squamous cell carcinoma (BSCC) is a rare variant of squamous cell carcinoma (SCC) of the esophagus. This study aimed to assess the discrepancy in clinicopathological characteristics and protein expression between esophageal BSCC and typical esophageal SCC.

Study Design

We reviewed 40 cases of esophageal BSCC. As controls, 63 well-differentiated SCC (WSCC) patients, 70 moderately differentiated SCC (MSCC) patients, and 51 poorly differentiated SCC (PSCC) patients were selected. The clinicopathologic characteristics and immunoreactivity of Ki-67, p53, p63, and epidermal growth factor receptor (EGFR) were then evaluated in the BSCC and typical SCC patients.

Results

The 5-year survival rates for the BSCC patients were 27.5%. The prognostic outcomes of the BSCC group were similar to those of the PSCC and MSCC groups but worse than that of the WSCC group, with a significant difference (P=0.045). Ki-67 expression was significantly higher in the BSCC group than that in the WSCC group (P < 0.05). Meanwhile, there were no significant differences in the expression of the other molecular markers (p53, p63, and EGFR) between the typical SCC and BSCC groups (P > 0.05). The median survival time of esophageal the BSCC patients with low p53 expression was significantly longer than that of the patients with high p53 expression (P=0.026). Further, the median survival time of the esophageal BSCC patients with high p63 expression was significantly longer than that of the patients with low p63 expression (P=0.041). Meanwhile, Ki-67 and EGFR expressions were not correlated with OS in the BSCC group.

Conclusion

Esophageal BSCC has a more clinically virulent course. Notably, p53 and p63 expression are associated with prognosis in BSCC. These findings conject that evaluation of multiple cancer biomarkers might be a promising auxiliary diagnostic indicator in BSCC.

Comparative Analysis of Clinical, Treatment, and Survival Characteristics of Basaloid and Squamous Cell Carcinoma of the Esophagus

BACKGROUND

Basaloid squamous cell carcinoma (BSC) is a rare variant of squamous cell carcinoma (SqCC) of the esophagus. Even though pathologically thought to be more aggressive than SqCC, there is discrepancy in the literature regarding the outcomes of BSC compared with those of SqCC.

STUDY DESIGN

We conducted a retrospective cohort study using the Surveillance Epidemiology and End Results (SEER) database. All patients with a histologic diagnosis of BSC and SqCC between 2004 and 2013 were included. We compared treatment and survival characteristics of patients with BSC and SqCC.

RESULTS

There were 16,158 patients included in this study; 173 patients (1.1%) had BSC. There were no significant differences between the 2 groups based on age, sex, marital status, insurance, or geographic region of diagnosis, but patients with BSC were more likely to be Caucasian (73.4% vs 64.7%; p = 0.017). Among staged patients, baseline tumor stage was similar in both groups. However, BSC tumors were more likely to be of high pathologic grade (56.8% vs 38.2%; p < 0.001). Patients with SqCC were more likely to receive radiation therapy (36.9% vs 53.9%; p < 0.001), while patients with BSC were more likely to undergo resection (32.4% vs 17.0%; p < 0.001). Median overall survival was similar in both groups (14 vs 9 months; log rank = 0.144), and this relationship persisted after stratification by treatment.

CONCLUSIONS

Even though more likely to be poorly differentiated at presentation, BSC of the esophagus seems to have similar clinical features and survival outcomes when compared with SqCC. Patients with BSC and SqCC should undergo stage-specific treatment to achieve optimal outcomes.