Open Access Highly Accessed Research article

High-incidence of PTEN mutations in Chinese patients with primary small cell carcinoma of the esophagus

Zhimin Zhang12, Hualiang Xiao3, Fei Xie1, Hui Zhang1, Chuan Chen1, He Xiao1, Zhenzhou Yang1, Dong Wang1, Zengpeng Li3 and Ge Wang1*

Author Affiliations

1 Cancer Center, Institute of Surgical Research, Daping Hospital, Third Military Medical University, Chongqing 400042, China

2 Department of Oncology, Wuhan General Hospital of Guangzhou Command, People’s Liberation Army, Wuhan, Hubei 430070, China

3 Department of pathology, Daping Hospital, Third Military Medical University, Chongqing 400042, China

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BMC Cancer 2014, 14:19  doi:10.1186/1471-2407-14-19

Published: 14 January 2014

Abstract

Background

Primary small cell carcinoma of the esophagus (PSCCE) is a rare and aggressive tumor with poor prognosis. The aim of this study was to investigate the existence of EGFR, KRAS, PIK3CA and PTEN mutations in PSCCE.

Methods

Clinical–pathological data and paraffin-embedded specimens were collected from 38 patients. Exons 18 to 21 of EGFR, KRAS and PIK3CA status were analyzed by real-time PCR based on ARMS and Scorpion technology in all patients, and the PTEN gene was also screened using real-time PCR and high-resolution melting curve analysis (HRMA).

Results

Only 1 (2.63%) out of 38 patients had EGFR mutations in L858R missense, and KRAS and PIK3CA were not found in the mutational spot in all patients. However, PTEN mutations presented in 14 (36.84%) out of 38 patients, including exon 5 coding for PTEN missense mutation (n =4, 10.53%), exon 6 (n =7, 18.42%), concurrent exon 5 and exon 6 (n =2, 5.26%), and exon 8 (n =1, 2.63%). Concurrent mutations of these genes were not detected in all samples. No statistically significant associations were found between the clinicopathological features and the mutation status of PTEN.

Conclusions

The incidence of PTEN mutations in Chinese patients with PSCCE was higher than that of previous reports in other histological subtypes of esophageal cancer.

Keywords:
Primary small cell carcinoma of the esophagus; PTEN; EGFR; KRAS; PIK3CA; Mutation