The p53 gene mutation is of prognostic value in esophageal squamous cell carcinoma patients in unified stages of curability

PRIMA-1 induces p53-mediated apoptosis by upregulating Noxa in esophageal squamous cell carcinoma with TP53 missense mutation

TP53 is associated with the resistance of cytotoxic treatment and patient prognosis, and the mutation rate of TP53 in esophageal squamous cell carcinoma (ESCC) is extraordinarily high, at over 90%. PRIMA‐1 (p53 re‐activation and induction of massive apoptosis) has recently been reported to restore the function of mutant TP53; however, its antitumor effect and mechanism in ESCC remain unclear. After evaluating the TP53 mutation status of a panel of 11 ESCC cell lines by Sanger sequencing, we assessed the in vitro effect of PRIMA‐1 administration on cells with different TP53 status by conducting cell viability and apoptosis assays. The expression levels of proteins in p53‐related pathways were examined by Western blotting, while knockdown studies were conducted to investigate the mechanism underlying PRIMA‐1's function. An ESCC xenograft model was further used to evaluate the therapeutic effect of PRIMA‐1 in vivo. PRIMA‐1 markedly inhibited cell growth and induced apoptosis by upregulating Noxa expression in ESCC cell lines with TP53 missense mutations, whereas no apoptosis was induced in ESCC with wild‐type TP53 and TP53 with frameshift and nonsense mutations. Importantly, the knockdown of Noxa canceled the apoptosis induced by PRIMA treatment in ESCC cell lines with TP53 missense mutations. PRIMA‐1 administration, compared with placebo, showed a significant antitumor effect by inducing Noxa in the xenograft model of an ESCC cell line with a TP53 missense mutation. PRIMA‐1 exhibits a significant antitumor effect, inducing massive apoptosis through the upregulation of Noxa in ESCC with TP53 missense mutations.

Current status of and perspectives regarding neoadjuvant chemoradiotherapy for locally advanced esophageal squamous cell carcinoma

The significance of neoadjuvant chemoradiotherapy (NACRT) for esophageal squamous cell carcinoma (ESCC) remains controversial with regard to the pathological response and long-term survival. We herein review the current status of and future perspectives regarding NACRT followed by esophagectomy for locally advanced ESCC. Some studies have suggested that a pathological complete response with NACRT is more common in patients with ESCC than in those with adenocarcinoma and that NACRT provided a survival benefit limited to patients with ESCC. However, NACRT may increase the risk of postoperative complications after esophagectomy. It is obvious that a favorable pathological response is the most important factor for obtaining a survival benefit, although no established parameters have been implemented clinically to predict the response to NACRT. Prospective clinical studies and basic research studies to identify predictive biomarkers for the response to NACRT are needed to aid in the development of NACRT treatment strategies for patients with ESCC.

A systematic review and meta-analysis of somatic and germline DNA sequence biomarkers of esophageal cancer survival, therapy response and stage

Recent advances in next generation sequencing reinforce the potential for DNA sequence markers to guide esophageal cancer management. We report the first systematic review and meta-analysis, identifying 94 markers of outcome and 41 of stage. Overall, evidence was poor. Meta-analyses demonstrated outcome associations for 6 tumor and 9 germline variants: priorities for prospective evaluation.

Introduction

There is an urgent need for biomarkers to help predict prognosis and guide management of esophageal cancer. This review identifies, evaluates and meta-analyses the evidence for reported somatic and germline DNA sequence biomarkers of outcome and stage.

Methods

A systematic review was carried out of the PubMed, EMBASE and Cochrane databases (20 August 2014), in conjunction with the ASCO Level of Evidence scale for biomarker research. Meta-analyses were carried out for all reported markers associated with outcome measures by more than one study.

Results

Four thousand and four articles were identified, 762 retrieved and 182 studies included. There were 65 reported markers of survival or recurrence 12 (18.5%) were excluded due to multiple comparisons. Following meta-analysis, significant associations were seen for six tumor variants (mutant TP53 and PIK3CA, copy number gain of ERBB2/HER2, CCND1 and FGF3, and chromosomal instability/ploidy) and seven germline polymorphisms: ERCC1 rs3212986, ERCC2 rs1799793, TP53 rs1042522, MDM2 rs2279744, TYMS rs34743033, ABCB1 rs1045642 and MTHFR rs1801133. Twelve germline markers of treatment complications were reported; 10 were excluded. Two tumor and 15 germline markers (11 excluded) of chemo (radio)therapy response were reported. Following meta-analysis, associations were demonstrated for mutant TP53, ERCC1 rs11615 and XRCC1 rs25487. There were 41 tumor/germline reported markers of stage; 27 (65.9%) were excluded.

Conclusions

Numerous DNA markers of outcome and stage have been reported, yet few are backed by high-quality evidence. Despite this, a small number of variants appear reliable. These merit evaluation in prospective trials, within the context of high-throughput sequencing and gene expression.

High expression of p300 has an unfavorable impact on survival in resectable esophageal squamous cell carcinoma

BACKGROUND

p300 is a transcriptional regulator that is involved in fundamental processes such as cell proliferation, cell differentiation, and tumor progression. However, its role and clinical significance in resectable esophageal squamous cell carcinoma (ESCC) has not been elucidated. The purpose of this study was to explore whether there was a correlation between the expression of p300 by immunohistochemistry and the clinical outcome of a group of patients with ESCC treated with surgical resection.

METHODS

Tissue microarray that included 240 surgically resected ESCC specimens and 56 cases of paracancerous tissues was successfully generated for immunohistochemical evaluation. The clinical and prognostic significance of p300 expression was analyzed statistically. Kaplan-Meier analysis was used to compare the postoperative survival between groups.

RESULTS

The expression frequency and expression levels of p300 were significantly higher in ESCC specimens (62.5%, 150 of 240) than in normal esophageal mucosa (8.9%, 5 of 56; p<0.001). Increased p300 expression was associated with higher histologic grade (p=0.012), T category (p=0.032), and N category (p=0.013). Patients with low expression of p300 demonstrated higher overall survival compared with those with high expression of p300 (mean, 80.0 months versus 56.9 months; p<0.001). A similar result was observed for disease-free survival (mean, 78.3 months versus 53.1 months; p<0.001). Furthermore, p300 expression could stratify the patient survival (disease-free survival and overall survival) in stage II (p=0.002, 0.003, respectively). Multivariate analysis showed that the level of p300 expression was an independent prognostic factor in ESCC (relative risk, 1.658; p=0.017).

CONCLUSIONS

High expression of p300 suggests poor prognosis for patients with resectable ESCC.

Loss of p53 in esophageal squamous cell carcinoma and the correlation with survival: analyses of gene mutations, protein expression, and loss of heterozygosity in Japanese patients

BACKGROUND

A high frequency of p53 protein expression or gene mutation has been reported in the early stages of esophageal squamous cell carcinoma (ESCC), and thus loss of p53 function is thought to be very important in esophageal carcinogenesis. However, there is controversy surrounding the correlation between p53 dysfunction and ESCC tumor progression. The complexity arises from the different modalities, such as mutation analysis, immunohistochemistry, and the detection of loss of heterozygosity (LOH) at the p53 genomic locus.

METHODS

In this study, we comprehensively analyzed p53 gene mutation, p53 protein expression, and LOH at 17p13 in 94 surgically resected Japanese cases of ESCC.

RESULTS

The frequency of p53 gene mutation was 60.6%. The rate of positive p53 protein expression was 56.4%. The frequency of LOH at 17p13 was 67.5%. There was a statistically significant correlation between the presence of a gene mutation and LOH, whereas, there was no significant correlation between gene mutation and protein expression.

CONCLUSIONS

Despite the importance of loss of p53 function in esophageal carcinogenesis, none of the examined parameters, either singly or combined, correlated with overall survival. Taken together, p53 function is a primary target for esophageal carcinogenesis but there is no apparent correlation with the malignant phenotype in ESCC.

Immunohistochemical evaluation for P53 and VEGF (Vascular Endothelial Growth Factor) is not prognostic for long term survival in end stage esophageal adenocarcinoma

OBJECTIVES

To correlate the expression of p53 protein and VEGF with the prognosis of patients submitted to curative resection to treat esophageal adenocarcinoma.

METHODS

Forty-six patients with esophageal adenocarcinoma, submitted to curative resection, were studied. The expressions of p53 protein and VEGF were assessed by immunohistochemistry in 52.2% and 47.8% of tumors, respectively.

RESULTS

P53 protein and VEGF expressions coincided in 26% of the cases, and no correlation between these expressions was observed. None of the clinicopathological factors showed a significant correlation with p53 protein or VEGF expressions. There was no significant association between p53 protein and VEGF expressions and long-term survival.

CONCLUSION

The expression of p53 protein and VEGF did not correlate with prognosis in esophageal adenocarcinoma patients submitted to curative resection.

p53 genotype predicts response to chemotherapy in patients with squamous cell carcinoma of the esophagus

BACKGROUND

Response to chemotherapy and anatomical spread are significant prognostic factors in patients with esophageal squamous cell carcinoma (ESCC) treated by chemotherapy then surgery. Predicting the response to chemotherapy would allow significant optimization of cancer treatment.

METHODS

Genomic mutation and protein expression of p53 were investigated retrospectively by polymerase chain reaction (PCR) single-strand conformation polymorphism (SSCP) and immunohistochemistry (IHC) using biopsy specimens from 77 ESCC patients before chemotherapy with 5-fluorouracil, adriamycin, and cisplatin. p53 status was correlated with various clinicopathological factors. Thereafter, we performed a prospective study of 20 consecutive patients to test our prediction model.

RESULTS

The retrospective study showed mutant p53 genotype and positive p53 IHC staining in 46.8 and 55.8% of patients, respectively, which was not associated with patient's clinicopathological findings including initial tumor stage. Objective response to chemotherapy was observed in 65.9% of patients with wild genotype, but in only 16.7% of patients with mutant genotype. Patients with mutations in p53 therefore showed significantly poorer prognosis than those without mutant p53. In contrast, p53 IHC staining did not correlate with response to chemotherapy, curative resection rate or prognosis. In the prospective study, p53 mutation was seen in 50% (10/20) of patients and was again consistently associated with poorer response to chemotherapy and poorer prognosis.

CONCLUSIONS

p53 genotype of pretreatment biopsy is a potentially useful predictor of response to chemotherapy and prognosis in ESCC patients. This information might be valuable to clinicians in deciding on the optimal clinical strategy in patients with ESCC.

p53 Mutations in carcinoma of the esophagus and gastroesophageal junction

BACKGROUND

Recent studies suggested p53 mutations as a prognostic factor. Tumors of the esophagus and gastroesophageal (GE) junction show raising incidence with a general poor prognosis.

METHODS

p53 Mutational spectra in 103 patients (68 squamous cell carcinoma/SCC and 35 adenocarcinoma/AC) were compared to clinical and pathologic data.

RESULTS AND CONCLUSIONS

p53 Mutations were found in 26 of 68 SSC (38.2%) and in 12 of 35 AC (34.5%). We only found G > T transversions in smokers with SCC. The survival of patients was not affected by p53 mutational status. In our study, the frequency and mutational spectrum of mutant p53 is similar in both histological types without prognostic relevance.

Deregulated p21(WAF1) overexpression impacts survival of surgically resected esophageal squamous cell carcinoma patients

BACKGROUND

Prognostic effects of cell cycle regulation associated tumor suppressor genes for esophageal squamous cell carcinoma patients are controversial. Clarifying the effects of these genes is beneficial for optimizing patient's outcome.

METHODS

Forty esophageal squamous cell carcinoma patients were included in the study. Tissue samples were analyzed for cell proliferation, DNA content, mutation of p53 gene, and expression of p21 and p53 proteins. Prognostic effects of these parameters were assessed by multivariate analysis.

RESULTS

Seventy-five percent of tumors exhibited aneuploid DNA content. Significantly higher S-phase fractions were detected in tumor samples (p < 0.001). The p53 gene mutated in 52.5% (21 of 40) of tumor samples, p53 immunostaining was detected in 62.5% (25 of 40) of tumor tissues and 50% of tumors over expressed p21. Overexpression of p21 protein did not correlate with p53 gene status, but significantly correlated with abnormal DNA content (p = 0.028). Advanced pTNM stage, lymph node metastasis and p21 overexpression conferred survival disadvantages in univariate analysis (p = 0.013, 0.045 and 0.017, respectively). A Cox multivariable analysis revealed pTNM stage (IIB/III/IV vs. I/IIA; p = 0.024) associated with p21 overexpression (positive vs. negative; p = 0.035) as independent prognostic factors in esophageal squamous cell carcinomas. Surprisingly, p21 overexpression significantly compromised the survival of patients with mutated p53 gene (p = 0.035). However, no significant dismal effect of p21 overexpression can be seen in patients with wild-type p53 gene (p = 0.175).

CONCLUSIONS

Overexpression of p21 correlates with chromosomal instability and serves as an adverse prognostic predictor for patients with esophageal squamous cell carcinoma. Its adverse effect is more prominent when the p53 gene is mutated.

Significance of preoperative C-reactive protein as a parameter of the perioperative course and long-term prognosis in squamous cell carcinoma and adenocarcinoma of the oesophagus

AIM: C-reactive protein (CRP) is an acute-phase reactant and a known indicator of the malignant potential of the tumour. The aim of this study was to investigate the significance of preoperative CRP as a parameter of the perioperative course and long-term prognosis in patients with squamous cell carcinoma and adenocarcinoma of the oesophagus.

METHODS: Serum CRP was determined preoperatively in 291 of 371 patients undergoing oesophagectomy for cancer from December 1989 to March 2004. Median patient age was 59 (28-79) year, 82.5% of patients were males. Squamous cell carcinoma was diagnosed in 151 (51.9%) and adenocarcinoma in 122 patients. Transhiatal oesophagectomy was done in 151 (51.9%) patients and 134 (46.0%) patients underwent the abdominothoracic procedure.

RESULTS: In 127 (43.6%) patients the preoperative serum CRP concentration was within the normal range (< 5 mg/dL), elevated CRP levels were measured in 164 (56.4%) patients. Tumour extension (P < 0.0005) and the number of lymph nodes affected by metastatic spread (P = 0.015) were significantly increased in the group with elevated CRP levels. Among the perioperative parameters both the number of blood transfusions (P = 0.006) and the general complication rate (P = 0.002) were higher in patients with elevated preoperative CRP levels. The long-term survival rate of 13.6 (0-109.8) mo was poorer in the group with elevated CRP levels compared to 18.9 (0-155.4) mo in the group with normal CRP levels (log-rank test: P = 0.107). Multivariate analysis with backward variables selection identified preoperative CRP as an independent prognostic factor of the long-term prognosis in patients with oesophageal carcinoma, with a hazard ratio of 1.182 (95% confidence interval: 1.030-1.356).

CONCLUSION: The preoperative serum CRP-level is an easily determined independent prognostic marker in patients with squamous cell carcinoma and adenocarcinoma of the oesophagus.

Phase I/II adenoviral p53 gene therapy for chemoradiation resistant advanced esophageal squamous cell carcinoma

We investigated the feasibility, safety, biological activity and therapeutic efficacy of adenovirus-mediated p53 gene transfer in patients with chemoradiation resistant advanced esophageal carcinoma. Eligible patients were not surgical candidates and had measurable, advanced squamous cell carcinoma of the esophagus that was resistant to chemoradiation therapy. On a 28-day cycle, intratumoral injections of Ad5CMV-p53 (INGN 201; ADVEXIN) were administered on days 1 and 3 at four dose levels (10 x 10(11) particles to 25 x 10(11) particles) and treated for up to five cycles. Ten patients received a total of 26 cycles with no dose-limiting toxicity. Administration of multiple courses was feasible and well-tolerated. Local tumor responses revealed stable disease in nine cases and progressive disease in one case. The overall responses were stable in six and progressive in four cases. Using polymerase chain reaction (PCR) analyses, gene transfer and p53 specific transgene expression were detected in tumor biopsy tissue from all patients. mRNA levels of p53, p21 and MDM2 increased in all but one case. Three patients showed absence of disease upon repeat biopsies. Substantial improvement in swallowing was observed in one patient with stenotic lesions. Intratumoral injection of Ad5CMV-p53 is safe, feasible and biologically active when administered in multiple doses to patients with esophageal cancer. Observations from this study indicate that this treatment results in local antitumor effects in chemoradiation resistant esophageal squamous cell carcinoma.

Prognostic value of p53 protein expression and vascular endothelial growth factor expression in resected squamous cell carcinoma of the esophagus

The most common genetic alterations found in a wide variety of cancers are p53 tumor suppressor gene mutations. p53 appears to be a nuclear transcription factor that plays a role in the control of cell proliferation, apoptosis, and the maintenance of genetic stability. Angiogenesis is a critical process in solid tumor growth and metastasis. Vascular endothelial growth factor (VEGF), a recently identified growth factor with significant angiogenic properties, may be a major tumor angiogenesis regulator. Few studies have investigated the association between p53 and VEGF expressions and prognosis in esophageal carcinoma. Forty-seven specimens resected from patients with stage II and III squamous cell carcinoma (SCC) of the esophagus were studied using immunohistochemical staining. VEGF and p53 expressions were observed in 40% and 53% of the tumors, respectively. The p53 and VEGF staining statuses were coincident in only 21% of the tumors, and no significant correlation was found between p53 and VEGF statuses. No clinicopathologic factors were significantly correlated with p53 or VEGF expression. No significant association between p53 and VEGF expressions and poor prognosis was found. In conclusion, p53 and VEGF were not correlated with prognosis in patients with stage II and III SCC of the esophagus.

Up-regulation of cyclooxygenase-2 in carcinogenesis of esophageal epithelia

AIM

To detect the expression of cyclooxygenase-2 gene and cell cycle related genes in the carcinogenesis of esophageal epithelia, so as to provide theoretical clues to the chemoprevention of esophageal carcinoma.

METHODS

The samples of esophageal epithelial cells were collected from the high incidence area of esophageal carcinoma. Cell smear slides were made for the evaluation of cell differentiation. The expression of COX-2, p53, p21/WAF1 and CDK4 were detected by flow cytometry.

RESULTS

The expression of COX-2 gene increased with the progression of epithelial cells from low grade dysplasia (LGD) to high grade dysplasia (HGD) or carcinoma. The fluorescence index (FI) was 1.54±0.27 in the carcinoma and suspected carcinoma groups, and the positive rate of COX-2 was 100%. The expression of mutant p53 and CDK4 also increased as the epithelial cells progressed toward carcinoma. But the expression of tumor suppressor gene p21/WAF1 was on the opposite, and its expression sharply decreased in the HGD and carcinoma or suspected carcinoma.

CONCLUSION

The expression of COX-2 gene significantly increase in the carcinogenesis of esophageal epithelia, and it also has the aberrant expression of cell cycle related genes.

Microsatellite instability in esophageal squamous cell carcinoma is not associated with hMLH1 promoter hypermethylation

To test whether a subset of esophageal squamous cell carcinomas (SCC) develop through a deficiency in DNA mismatch repair, we examined microsatellite instability (MSI) using 11 microsatellite markers including BAT-26, hMLH1 protein expression by immunohistochemistry, and methylation status of the hMLH1 promoter by methylation-specific polymerase chain reaction (MSP). p53 mutations were also investigated. Microsatellite instability at one or more loci was observed in 40% (12/30) of esophageal SCC tumor samples, although only one of these tumors was categorized as high-frequency MSI (MSI-H) and none showed BAT-26 instability. While immunohistochemistry revealed decreased hMLH1 protein expression in 27% (8/30) of the tumors, hMLH1 promoter hypermethylation was not observed. Absence of hMLH1 protein expression was relatively common in well-differentiated (keratinizing-type) esophageal SCC, but was not associated with hMLH1 promoter hypermethylation. p53 mutation was detected in 37% (11/30) and loss of heterozygosity (LOH) in 90% (27/30) of esophageal SCC samples. Our results suggested that most esophageal SCC develop through defects in tumor suppressor genes (i.e. the suppressor pathway), and that MSI in esophageal SCC probably represent random replication errors rather than being associated with DNA mismatch repair deficiency.

p53 gene therapy for esophageal cancer

Despite improvement of surgical treatment and application of multimodality therapies to advanced esophageal cancer, the prognosis is extremely poor for patients with unresectable tumors. Based on the genetic background of esophageal cancer, we have developed various gene therapy strategies against human esophageal cancer. In this article, we review molecular events of esophageal cancer and p53 gene therapy approaches for its treatment. First, we analyzed p53 genetic alterations and angiogenesis in esophageal cancer. Second, we tested a p53 recombinant adenoviral vector (Ad5CMV-p53). Significant growth suppression was observed following infection with Ad5CMV-p53 in human esophageal cancer cell lines. This observation suggests that Ad5CMV-p53 may be a potentially effective therapeutic agent for locally advanced esophageal cancer. Promising avenues for investigation include double gene therapy and adjuvant use of gene therapy with radiation therapy. Third, based on recent reports of clinical trials of p53 gene therapy for lung cancer and head and neck cancer, we developed a clinical protocol for p53 gene therapy for unresectable advanced esophageal cancer. This clinical trial was planned to evaluate vector tolerability and efficacy. Up to December 1, 2001, four patients were enrolled in this phase I/II trial. No serious adverse events related to Ad5CMV-p53 have occurred so far in these patients, and the trial has been safely conducted.

Facilitation of adenoviral wild-type p53-induced apoptotic cell death by overexpression of p33(ING1) in T.Tn human esophageal carcinoma cells

To investigate the effect of p33(ING1) on wild-type p53 gene therapy, T.Tn human esophageal carcinoma cells were stably transfected with p33(ING1) cDNA. Infection with Ad-p53 (recombinant adenovirus containing wild-type p53) into p33-transfected cells reduced cell viability, while infection with empty vector had little effect. This reduced viability was shown to be due to apoptotic cell death by the TUNEL (terminal deoxynucleotidyl transferase-mediated nick end-labeling) assay. Following infection with Ad-p53, levels of p53 were similar in p33-expressing cells and in the parental line. However, levels of p21 and Mdm2 were elevated in p33-transfected cells. Nonetheless, this enhanced expression of Mdm2 appeared to be ineffective in downregulating p53. Transient transfection with mutant Mdm2 prior to Ad-p53 infection provided a significant protection as compared with cells transfected with wild-type Mdm2. These results imply a synergistic effect between p33 and p53 in the induction of apoptosis of human esophageal carcinoma cells. A role for Mdm2 in this synergism is suggested.

Expression of angiogenic factors predicts response to chemoradiotherapy and prognosis of oesophageal squamous cell carcinoma

The ability to predict patients' responses to chemoradiotherapy by analyzing pre-treatment biopsy specimens would be valuable for managing oesophageal squamous-cell cancer. To this end, the expression of p53, thymidine phosphorylase and vascular endothelial cell growth factor was analyzed by immunohistochemistry in 52 patients with oesophageal squamous-cell cancer prior to chemoradiotherapy. Treatment consisted of radiotherapy (40 Gy) and 5 day-infusion of 5-Fluorouracil (500 mg m(-2) per day) combined with cisplatin (10 mg m(-2) per day). Following treatment, imaging and endoscopic reassessment was performed to establish treatment response. Thirty-one patients underwent radical surgery and 21 patients were treated with an additional 20 Gy of radiotherapy. Of the tumours studied, 58% were p53-positive, 40% thymidine phosphorylase-positive and 44% vascular endothelial cell growth factor-positive. A clinical response was observed in 36 patients (69%) and was negatively associated with thymidine phosphorylase expression (P=0.02) and vascular endothelial cell growth factor expression (P<0.001). However, the 5-year survival rate was significantly lower only in patients with vascular endothelial cell growth factor-positive tumours (P=0.037). Multivariate analysis identified vascular endothelial cell growth factor as a significant independent prognostic factor (P=0.0147). These results suggest that expression of angiogenic factors has predictive value for the treatment response and outcome of patients with oesophageal cancer.

Significance of preoperative elevation of serum C-reactive protein as an indicator of prognosis in esophageal carcinoma

BACKGROUND

Preoperative elevation of serum C-reactive protein (CRP) has been reported to be a prognostic indicator in gastric carcinoma and colorectal carcinoma. The aim of this study was to establish the significance of preoperative elevation of serum CRP as an indicator of prognosis in patients with esophageal carcinoma.

METHODS

Two hundred sixty-two patients with esophageal carcinoma who had been treated by esophageal resection and reconstruction of digestive tracts were evaluated, excluding patients with neoplasms in other organs. Preoperative serum CRP was measured, and the relation between the elevation of serum CRP and the clinicopathological factors and prognosis of the patients was investigated.

RESULTS

The mean size of the tumors and the proportions of lymph node metastasis and lymphatic invasion were significantly larger in patients with preoperative elevation of serum CRP than in patients without preoperative elevation of serum CRP (5.8 +/- 2.5 cm versus 4.8 +/- 2.5 cm, P <0.01, 59.5% versus 35.4%, P <0.001, and 35.7% versus 23.6%, P <0.05, respectively). 1-, 3-, and 5-year survival rates in patients with preoperative elevation of serum CRP (60.6%, 18.4%, and 11.5%, respectively) were significantly lower than those in patients without preoperative elevation of serum CRP (88.7%, 70.9%, and 68.4%, respectively; P <0.0001). Multivariate analysis demonstrated that the preoperative elevation of serum CRP was an independent prognostic factor in esophageal carcinoma (P <0.0001).

CONCLUSIONS

The preoperative serum elevation of CRP can be a marker of the malignant potential of the tumor and an independent prognostic indicator in esophageal carcinoma.

p53 expression in squamous dysplasia associated with carcinoma of the oesophagus: evidence for field carcinogenesis

Squamous epithelial dysplasia is often observed multifocally in the cancerous oesophagus and is presumably considered to be a pre-cancerous lesion. A mutation of the p53 tumour suppressor gene is commonly identified in oesophageal cancer and dysplasia. p53 mutations can be anticipated immunohistochemically. In order to confirm the biological and clinical significance of p53 expressions in oesophageal field carcinogenesis, immunostaining for p53 in cancerous and multifocal precancerous lesions from resected human oesophagus was systematically investigated, while paying special attention to the contiguity of these lesions. Lesions expressing p53 were detected in 46.5% (20 of 43 lesions) of the invasive carcinoma, and in 51.0% (46 of 90 lesions) of the carcinoma in situ, and in 51.4% (92 of 179 lesions) of the dysplasia. Next, the p53 expression in dysplasia was compared with that in carcinoma for the same case. 37 of 39 (94.8%) dysplasias contiguous to p53-positive carcinomas also expressed p53 (P<0.0001). On the other hand, the isolated dysplasias without contiguity to p53-positive carcinomas, only expressed p53 protein in 44.0% (11 of 25 lesions). No significant correlations were found between the p53 staining and either the clinicopathological features or prognosis. Discordant p53 alterations, such as those seen in cancerous and isolated precancerous lesions, may thus demonstrate further evidence for a multicentric or field carcinogenesis of the human oesophagus.

Surgery, radiotherapy, and chemotherapy in carcinoma of the esophagus

Esophageal carcinoma remains a highly lethal disease that has shown a recent profound increase in prevalence and an equally dramatic epidemiologic shift. There is a well recognized causal association between gastroesophageal reflux disease and adenocarcinoma of the esophagus, and the molecular events underlying this progression from mucosal injury, to metaplasia, to dysplasia, to carcinoma are now becoming clear. Current diagnostic modalities and preoperative staging systems all have significant limitations. Fortunately, chemoprevention strategies and the identification of clinically useful molecular biomarkers that may be used to stage disease and select appropriate therapy are on the horizon. The extent of surgical resection for esophageal carcinoma remains an area of great controversy. Disease that is confined to the mucosa is being diagnosed more commonly, and endoscopic ablative techniques have been proposed. To date, however, preoperative discrimination of tumor depth and presence of regional nodal metastases remains inadequate in these very early lesions, and caution is urged before adopting therapies that may compromise cure. For disease penetrating the mucosa, the extent of surgical therapy must be tailored by the objectives of treatment (cure vs palliation) and preoperative stage. Surgical resection is the current standard of care, with combined-modality therapy reserved for prohibitive surgical candidates. No clear survival benefit has been documented for neoadjuvant radiotherapy or chemotherapy alone. The results of preoperative combined-modality therapy, including three prospective, randomized trials, are encouraging but to date have not shown a definite benefit.