P53 gene protein overexpression predicts results of trimodality therapy in esophageal cancer patients

Examined lymph node count is not associated with prognosis in elderly patients with pN0 thoracic esophageal cancer

The purpose of this study was to determine whether the number of lymph nodes dissected predicts prognosis in surgically treated elderly patients with pN0 thoracic esophageal cancer. We searched the Surveillance, Epidemiology, and End Results database and identified the records of younger (<75 years) and older (≥75 years) patients with pN0 thoracic esophageal cancer between 1998 and 2015. The patient characteristics, tumor data, and postoperative variables were analyzed in this study. The Kaplan-Meier method and a Cox proportional hazard model were used to compare overall and cause-specific survival. Data from 1,792 esophageal cancer patients (older: n = 295; younger: n = 1497) were included. The survival analysis showed that the overall and cause-specific survival in the patients with ≥15 examined lymph nodes (eLNs) was significantly superior to that in the patients with 1 to 14 eLNs (P < .001); however, the difference disappeared in the older patients. After stratification by the tumor location, histology, pT classification, and differentiation between the younger and older cohorts to analyze the association between eLNs and survival, we found that the differences remained significant in most subgroups in the younger cohort. There were no differences in any subgroups of older patients. This study replicated the previously identified finding that long-term survival in patients with extensive lymphadenectomy was significantly superior to that in patients with less extensive lymphadenectomy. However, less extensive lymphadenectomy may be an acceptable treatment modality for elderly patients with pN0 thoracic esophageal cancer.

CecropinXJ, a silkworm antimicrobial peptide, induces cytoskeleton disruption in esophageal carcinoma cells

Antimicrobial peptides exist in the non-specific immune system of organism and participate in the innate host defense of each species. CecropinXJ, a cationic antimicrobial peptide, possesses potent anticancer activity and acts preferentially on cancer cells instead of normal cells, but the mechanism of cancer cell death induced by cecropinXJ remains largely unknown. This study was performed to investigate the cytoskeleton-disrupting effects of cecropinXJ on human esophageal carcinoma cell line Eca109 using scanning electron microscopy observation, fluorescence imaging, cell migration and invasion assays, western blotting, and quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis. The electronic microscope and fluorescence imaging observation suggested that cecropinXJ could result in morphological changes and induce damage to microtubules and actin of Eca109 cells in a dose-dependent manner. The cell migration and invasion assays demonstrated that cecropinXJ could inhibit migration and invasion of tumor cells. Western blot and qRT-PCR analysis showed that there was obvious correlation between microtubule depolymerization and actin polymerization induced by cecropinXJ. Moreover, cecropinXJ might also cause decreased expression of α-actin, β-actin, γ-actin, α-tubulin, and β-tubulin genes in concentration- and time-dependent manners. In summary, this study indicates that cecropinXJ triggers cytotoxicity in Eca109 cells through inducing the cytoskeleton destruction and regulating the expression of cytoskeleton proteins. This cecropinXJ-mediated cytoskeleton-destruction effect is instrumental in our understanding of the detailed action of antimicrobial peptides in human cancer cells and cecropinXJ might be a potential therapeutic agent for the treatment of cancer in the future.

Biomarkers for predicting the response of esophageal squamous cell carcinoma to neoadjuvant chemoradiation therapy

This review summarizes and evaluates the literature regarding the biomarkers for predicting the response and/or prognosis of esophageal squamous cell carcinoma (ESCC) patients treated with neoadjuvant chemoradiation therapy (CRT). There are seven categories of molecules known to correlate with the response and/or prognosis: tumor suppressors (p53, p21), cell cycle regulators (Cyclin D1, CDC25B, 14-3-3sigma), DNA repair molecules (p53R2, ERCC1), drug resistance proteins [metallothionein (MT)], angiogenic factors (VEGF), molecules involved in cell proliferation/invasion/metastasis (Ki-67, COX-2) and hedgehog signaling molecules (Gli-1). Of the above molecules, the tumor suppressor p53 is expected to be a representative biomarker for predicting the response and prognosis. The cell cycle markers CDC25B and 14-3-3sigma have potential as response biomarkers independent of the p53 status. The DNA repair markers, p53R2 or ERCC1, angiogenic molecule (VEGF), and hedgehog signaling pathway factor Gli-1 also have potential to predict the response and prognosis of ESCC. However, there are still many unanswered questions with regard to predicting the clinical effects of neoadjuvant CRT.

Correlation of p53 status with the response to chemotherapy-based treatment in esophageal cancer: a meta-analysis

BACKGROUND

The value of p53 status for predicting response to chemotherapy-based treatment in patients with esophageal cancer has been controversial. We conducted a meta-analysis to elucidate the correlation of p53 status with the response to chemotherapy-based treatment.

METHODS

Studies were searched in PubMed, Embase, and Web of Science (up to September 2012). The p53 status and response to therapy were defined and standardized. Subgroup analyses based on the treatment and histopathology were performed to explore the usefulness of p53 status for predicting response to therapy in esophageal cancer. Sensitivity analyses were conducted by removing specific studies to assess the effects of study quality.

RESULTS

We included 28 studies with 1497 cases in our meta-analysis. Wild-type form of p53 status (low expression of p53 protein and/or wild-type p53 gene) was associated with high response to chemotherapy-based treatment in esophageal cancer (total major response [MR]: risk ratio [RR] = 1.09, 95 % CI = 1.03-1.16, P = .003; pathological MR: RR = 1.15, 95 % CI = 1.06-1.25, P = .001; total complete response [CR]: RR = 1.08, 95 % CI = 1.00-1.17, P = .040). The similar correlation between the wild-type form p53 and response to therapy were also detected in subgroup analyses (total MR, pathological MR, and total CR in chemoradiotherapy subgroup; total MR in chemotherapy subgroup; total MR and pathological CR in esophageal squamous cell carcinoma [ESCC]). Additionally, patients with wild-type form p53 status had high pathological complete response rate to neoadjuvant chemoradiotherapy in ESCC.

CONCLUSIONS

The current meta-analysis suggested that p53 status might be a predictive biomarker for response to chemotherapy-based treatment in esophageal cancer.

Effect of S1P5 on proliferation and migration of human esophageal cancer cells

AIM: To investigate the sphingosine 1-phosphate (S1P) receptor expression profile in human esophageal cancer cells and the effects of S1P5 on proliferation and migration of human esophageal cancer cells.

METHODS: S1P receptor expression profile in human esophageal squamous cell carcinoma cell line Eca109 was detected by semi-quantitative reverse transcription polymerase chain reaction. Eca109 cells were stably transfected with S1P5-EGFP or control-EGFP constructs. The relation between the responses of cell proliferation and migration to S1P and S1P5 expression was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and migration assay, respectively.

RESULTS: Both normal human esophageal mucosal epithelium and Eca109 cells expressed S1P1, S1P2, S1P3 and S1P5, respectively. Esophageal mucosal epithelium expressed S1P5 at a higher level than Eca109 cell line. S1P5 over-expressing Eca109 cells displayed spindle cell morphology with elongated and extended filopodia-like projections. The proliferation response of S1P5-transfected Eca109 cells was lower than that of control vector-transfected cells with or without S1P stimulation (P < 0.05 or 0.01). S1P significantly inhibited the migration of S1P5-transfected Eca109 cells (P < 0.001). However, without S1P in transwell lower chamber, the number of migrated S1P5-transfected Eca109 cells was greater than that of control vector-transfected Eca109 cells (P < 0.001).

CONCLUSION: S1P binding to S1P5 inhibits the proliferation and migration of S1P5-transfected Eca109 cells. Esophageal cancer cells may down-regulate the expression of S1P5 to escape the inhibitory effect.

The predictive value of molecular markers (p53, EGFR, ATM, CHK2) in multimodally treated squamous cell carcinoma of the oesophagus

Pretherapeutic identification of oesophageal squamous cell carcinomas that will respond to neoadjuvant chemoradiotherapy is an important attempt for improvement of patient's prognosis. In the current study, pretherapeutic biopsies from 94 oesophageal squamous cell carcinomas (cT3, cN0/+, cM0) in patients who underwent neoadjuvant chemoradiotherapy (RCTx: 45 Gy plus cisplatin and 5-fluorouracil) and subsequent oesophagectomy in the setting of a single-centre prospective treatment trial were investigated by means of immunohistochemistry. Expression of proteins involved in DNA repair and/or cell-cycle regulation, that is p53, p53 (phosphorylated at Ser15), EGFR, ATM protein kinase (phosphorylated at Ser1981) and checkpoint kinase 2 (CHK2) (phosphorylated at Thr68) was correlated with the response to RCTx and with overall survival. Tumours that were positive for CHK2 expression more frequently showed clinically determined regression after RCTx (69.4%) than tumours that were negative for CHK2 expression (32.1%; P=0.0011), whereas other parameters did not correlate with tumour regression. Expression of ATM correlated with expression of CHK2 (P=0.0061) and p53-phospho (P=0.0064). Expression of p53 correlated with expression of p53-phospho (P<0.0001). In contrast to clinical and histopathological response evaluation, none of the molecular parameters under investigation correlated with overall survival. In conclusion, expression analysis of p53, EGFR CHK2 and ATM has no predictive value in multimodally treated oesophageal squamous cell carcinoma.

Down-regulation of Bcl-XL by RNA interference suppresses cell growth and induces apoptosis in human esophageal cancer cells

AIM: To determine the inhibitory effect of the vector-generated small interfering RNAs (siRNAs) on the expression of the Bcl-X_L gene in established human esophageal cancer cells, and to investigate the effect of the Bcl-X_L siRNAs on cell growth and apoptosis in esophageal cancer cells.

METHODS: Three siRNA-expressing vectors targeting different sites of the Bcl-X_L gene were constructed from pTZ-U6+1 vector. Cultured esophageal cancer cells were transfected with the siRNA-expressing vector (or the control vector) using lipofectamine 2000. Bcl-X_L gene expression was determined with semiquantitative RT-PCR assay and Western blotting. Among the three siRNA-expressing vectors, the most highly functional vector and its effect on cell growth and apoptosis in esophageal cancer cells was further analyzed.

RESULTS: Of the three siRNA-expressing vectors, siRNA-expressing vector No.1 was the most potent one which suppressed Bcl-X_L mRNA production to 32.5% of that in the untreated esophageal cancer cells. Western blotting analysis showed that siRNA-expressing vector No.1 markedly down-regulated the expression of Bcl-X_L in human esophageal cancer cells. Treatment of esophageal cancer cells with siRNA-expressing vector No.1 resulted in inhibition of cell growth and induction of apoptosis.

CONCLUSION: Down-regulation of Bcl-X_L by vector-generated small interfering RNAs can suppress cell growth and induce apoptosis in human esophageal cancer cells.

Lack of prognostic impact of p53 gene mutation and p53 phosphorylation at serine 15 in multimodally treated adenocarcinomas of the gastroesophageal junction

PURPOSE

As inactivation of p53 may be correlated with poor response of tumors to chemo- and/or radiotherapy the presence of p53 mutations in exons 5-8 was determined in adenocarcinomas of the gastroesophageal junction (GEJ). As p53 protein phosphorylation at serine 15 indicates stabilization and protection against mdm-2 the presence of this phosphorylation state was subsequently evaluated.

METHODS

Mutations in exons 5-8 were analyzed by denaturing high pressure liquid chromatography (DHPLC) and subsequent sequence analysis in pretherapeutic biopsies of 38 adenocarcinomas of the GEJ that had undergone multimodal treatment in the course of a prospective multicentric phase III trial. The presence of p53 protein phosphorylation at serine 15 was evaluated by immunohistochemistry.

RESULTS

Mutations in the DNA binding region were found in 23 samples and were only weakly associated with worse 2-year survival (P=0.083). Phosphorylation at serine 15 of p53 was detected in 14 samples, being neither associated with p53 mutation nor with patient's survival.

CONCLUSION

This allows the conclusion that the determination of these two parameters does not help to select patients who do profit from multimodal treatment for adenocarcinomas of the GEJ.

Expression of p21(Waf1/Cip1) predicts response and survival of esophageal cancer patients treated by chemoradiotherapy

Chemoradiotherapy is a multimodal therapy routinely used as a primary treatment for advanced esophageal cancer. However, it is beneficial only to patients who respond. To identify pretreatment markers predicting response and survival, we examined the expression of cell cycle regulatory molecules, p53, p21(Waf1/Cip1) cyclin D1, and CDC25B, in biopsy specimens from 76 patients with stage III and stage IV squamous cell carcinoma. Overexpression of p53, p21, cyclin D1 and CDC25B was observed in 58%, 30%, 28%, and 32% of patients, respectively. The expression of p21 correlated significantly with response to chemoradiotherapy (P = 0.0001). Survival of patients with p21-expressing tumors was better than that of patients with p21-negative tumors (P = 0.013). Expression of other genes was not significantly correlated with treatment response and survival. In patients with p53-negative tumors, survival of those patients with p21-positive tumors was significantly higher than that of those with p21-negative tumors (P = 0.0452), but no significant difference was found in patients with p53-positive tumors. Multivariate analysis revealed that p21 expression was an independent variable among pretreatment parameters in predicting survival. These results suggest that p21 expression is potentially useful for predicting the response to chemoradiotherapy and survival of patients with advanced esophageal squamous cell cancer.

p27 and Barrett's esophagus: a review*

The rising prevalence of Barrett's esophagus and Barrett's associated adenocarcinoma in the Western world has stimulated increasing interest in this disease. This has resulted in a plethora of articles concerning its molecular biology, but the tumor suppressor gene, p27, has received little attention. In this article, we review the literature concerning the role of p27 in Barrett's esophagus and its malignant transformation, and we evaluate its possible role as an important clinical biomarker, as well as potential chemopreventive clinical agents aimed at substituting its antitumoral activity.

The expressions of p21 and pRB may be good indicators for the sensitivity of esophageal squamous cell cancers to CPT-11: Cell proliferation activity correlates with the effect of CPT-11

Previously, we demonstrated that CPT-11 is an effective agent against esophageal squamous cell cancers (ESCC), and that the protein level of DNA topoisomerase I can be a predictor for sensitivity to CPT-11 (Jpn J Cancer Res 2001; 92: 1335-41). Here, we describe our search for additional predictors of sensitivity to CPT-11, mainly among cell cycle-regulating proteins, because the cytotoxicity of CPT-11 is significantly correlated with the percentage of ESCC cells in S-phase. To this end, we selected and examined the expressions of 5 proteins involved in G1-S transition, i.e., p53, cyclin D1, p21, p27, and pRB, in 14 ESCC cell lines by western blot analysis. Among these proteins, the expression levels of p21 and pRB showed significant differences that were associated with the IC50 values for CPT-11 (P = 0.0339 and P = 0.0109, respectively). Namely, the expression of p21 or pRB independently could be a good indicator of CPT-11 efficacy in ESCC. In addition, the cell proliferation activities examined by enzyme-linked immunosorbent assay (ELISA) using 5-bromo-2'-deoxyuridine (BrdU) showed a significant correlation with the percentage of total S-phase cells (correlation coefficient = 0.568, P = 0.0324), and an inverse correlation with the IC50 values for CPT-11 (correlation coefficient =-0.601, P = 0.0213). Because, as in the case of DNA topoisomerase I, the cell proliferation activity determined using BrdU shows a close relationship with the MIB-1 labeling index, immunohistochemical studies of p21, pRB, and MIB-1 in resected ESCC specimens and/or biopsy samples could make it possible to predict more precisely the sensitivity of ESCC patients to CPT-11 prior to treatment.

Immunohistochemistry analysis of micrometastasis in pretreatment lymph nodes from patients with esophageal cancer

BACKGROUND

With recent advances in neoadjuvant therapy in esophageal cancer, pretreatment lymph node staging has become increasingly important in stratifying patients to appropriate treatment regimens and for prognostication. Immunohistochemical analysis (IHC) using epithelial markers has been shown to identify micrometastases in histologically negative lymph nodes. We performed this study to evaluate if IHC analysis in thoracoscopic/laparoscopic (Ts/Ls) pretreatment staging lymph nodes can reveal additional diagnostic information to routine histopathology.

METHODS

Specimens of 106 patients with esophageal cancer who had pretreatment Ts/Ls staging were retrospectively studied. Lymph node biopsies were obtained for IHC staining using cytokeratin (CK) of AE1/AE3. IHC staining for p53, an apoptosis protein associated with poor prognosis in esophageal cancer, was also performed.

RESULTS

331 Ts/Ls staging lymph node biopsies were collected from 106 patients. A total of 15.4% (51/331) of the lymph nodes or 34.9% (37/106) of patients were found to have metastatic deposits by routine histology. All the histologically positive lymph nodes were CK positive. Among the remaining 280 histologically negative lymph nodes, 11(3.9%) were found to have micrometastasis by CK staining. Three patients (4.3%, 3/69) were upstaged from N0 to N1. They died of early recurrences after treatment. A total of 67.6% (25/37) of the patients with histologically positive lymph node were p53 positive. No histologically negative lymph node was found to be p53 positive in this series.

CONCLUSIONS

Immunohistochemical analysis for CK can detect micrometastatic involvement of lymph nodes that are missed on routine pathologic examination, and, therefore, can improve lymph node staging. Its clinical significance in esophageal cancer warrants further study.

Current status of neoadjuvant therapy for adenocarcinoma of the distal esophagus

Prospective studies dealing with preoperative therapy in adenocarcinoma of the esophagus alone are rare. The interpretation of the preferential phase II trials and a few phase III trials is complicated, as most studies include adenocarcinoma of the esophagus (i.e., Barrett's carcinoma), adenocarcinoma of the esophagogastric junction (including cardia carcinoma and subcardia carcinoma), or squamous cell carcinoma. Preoperative chemotherapy, generally well tolerated, cannot decrease the incidence of local failure beyond the level achieved with surgery alone, but it might delay systemic relapse. Preoperative radiotherapy can enhance local control, but it fails to improve overall survival. Neoadjuvant chemoradiation was demonstrated in only one randomized trail to have a survival benefit, but survival in the surgery-alone group was unusually low. Generally, survival was ameliorated in patients responding to neoadjuvant treatment. However, preoperative chemoradiation was often accompanied by a remarkable increase in postoperative morbidity and mortality. Nonresponding patients have, in this respect, a worse prognosis than responders after resection. The prediction of responding patients to neoadjuvant therapy as well as the early identification of patients who will not respond is of utmost clinical importance. Today, there is no absolute evidence that neoadjuvant treatment for patients with potentially resectable Barrett's cancer prolongs survival. In patients with locally advanced, presumably not completely resectable adenocarcinoma of the esophagus, preoperative treatment appears to increase the chance for a curative resection and enhance survival in responding patients. Neoadjuvant treatment of adenocarcinoma of the esophagus, as a consequence, is currently not the standard treatment and should be performed only within controlled clinical trials.

Clinical implications of p53 tumor suppressor gene mutation and protein expression in esophageal adenocarcinomas: results of a ten-year prospective study

OBJECTIVE

This study was undertaken to characterize the spectrum of p53 alterations (mutations and protein expression) in surgically resected esophageal adenocarcinomas, and to correlate molecular alterations with clinicopathologic findings and outcome.

METHODS

Between 1991 and 2001, 91 consecutive patients with esophageal adenocarcinomas underwent subtotal esophagectomy. No patient received induction therapy. Strict clinicopathologic criteria were used to define primary esophageal adenocarcinomas. Genomic DNA was extracted from esophageal tumors, each matched with histologically normal esophageal epithelium (internal control) from the resection margin. Polymerase chain reaction was used to amplify p53 exons 4 through 10. Mutations were studied by single-strand conformation polymorphism analysis and direct DNA sequencing. Immunohistochemical testing (monoclonal antibody DO7) was used to evaluate p53 protein distribution.

RESULTS

Five-year overall survival was 27.3%. No p53 alterations (mutations and/or protein overexpression) were found in normal esophageal epithelium. A total of 57.1% (n = 52) of tumors had p53 alterations (mutations and/or protein overexpression), which on univariate analysis were associated with poor tumor differentiation (P =.001), advanced pTNM stage (P =.009), and number of involved lymph nodes (0, 1-3, >3; P =.04). Patients with p53 alterations had significantly reduced 5-year overall survival relative to patients with wild-type p53 (15% vs 46%; P =.004). The p53 mutations were predominantly G:C to A:T transitions at CpG dinucleotides (52.2%, 24/46)

CONCLUSIONS

We conclude that p53 alterations (mutations and/or protein overexpression) are a predictor of reduced postoperative survival after surgical resection of esophageal adenocarcinomas and that p53 may be a clinically useful molecular marker for stratifying patients in future clinical trials. Patterns of p53 mutations suggest endogenous mutational mechanisms.

Thoracoscopy/laparoscopy in the staging of esophageal cancer: Maryland experience

Precise clinical staging of esophageal cancer before treatment is important. Thoracoscopic/laparoscopic (Ts/Ls) staging has been proposed as a promising staging method. This study was conducted to evaluate the potential benefits of Ts/Ls staging over conventional noninvasive clinical staging in patients with esophageal cancer. From 1991 to 1999, 111 patients with esophageal cancer underwent Ts/Ls staging by the University of Maryland Medical System. Pretreatment staging workup included computed tomography, magnetic resonance imaging, and esophageal ultrasonography, followed by Ts/Ls surgical staging. Thoracoscopy was successfully performed in 102 patients and was aborted in 4 patients because of pleural adhesions. Laparoscopy was successfully done in 76 patients and was aborted in 1 patient because of peritoneal adhesion. Sixty-seven patients had both Ts and Ls staging, whereas 35 patients and 9 patients, respectively, had only Ts or Ls staging. Thirteen of 19 patients with clinical T4 disease were downstaged to T3 disease, and 8 patients with clinical T3 disease were upstaged to T4 by Ts/Ls staging. No clinical T1-2 disease was found to be associated with local invasion (T4) by Ts/Ls. Forty-eight and 19 patients had mediastinal and celiac lymph node metastases clinically diagnosed, respectively. Nine (18.8%) and 12 (63.2%) of them were proved by Ts and Ls, respectively. An additional 5 and 16 patients were found to have unexpected mediastinal and celiac lymph node metastases, respectively, by Ts/Ls. Biopsy specimens of pleura, lung, or liver were obtained by Ts/Ls procedures in 17 patients because of suspicious findings of routine imaging studies or unexpected findings during the staging operation. Five patients were found to have distant metastasis, and the presence of metastases in others was excluded. The correlation between Ts/Ls staging and conventional noninvasive clinical staging in the diagnosis of T4 disease, mediastinal lymph node metastasis, celiac lymph node metastasis, and M1 disease was 18.8%, 14.5%, 25.5%, and 20.0%, respectively. Ts/Ls provides more accurate information for evaluating local invasion, lymph node metastasis, and distant metastasis. The poor correlation of staging diagnosis between Ts/Ls and conventional noninvasive clinical examinations suggests that the accuracy of current noninvasive clinical staging is questionable and needs to be improved.

Multimodality therapy for esophageal cancer

Esophageal cancer is undergoing a major shift in its epidemiology. Its incidence is dramatically growing and it more commonly affects younger and healthier patients. Based on the published data, there is no strong evidence to recommend routine preoperative chemotherapy for the treatment of surgically resectable esophageal carcinoma. It might be that a large-scale randomized study-which will be published in the near future-will shed some different light on this subject. The role of preoperative CRT remains undetermined. To settle this issue, larger, clinical, controlled trials are needed. Improvement in the preoperative regimen and use of new drugs should be evaluated. Concomitant CRT should be considered for potential benefit in survival and local control in patients who have localized disease and are candidates for radical non-surgical treatment. Patients with pCR following neoadjuvant therapy have a consistent, substantial survival benefit. Biologic markers can be used to predict response to therapy and might allow designation of treatment based on the individual tumor. Pretreatment staging is necessary for standardization of patients undergoing treatment protocols and for outcome evaluation. Pretreatment staging will be even more important in the future for adjusting treatment to individual patient. Video-assisted thoracoscopy and laparoscopy have been found to be the most accurate lymph node staging techniques.

Expression of heat shock protein 70 in grossly resected esophageal squamous cell carcinoma

BACKGROUND

The aim of the present study was to use immunohistochemical methods to clarify the clinical implication of heat shock protein (HSP) 70 expression in esophageal squamous cell carcinoma and to investigate the function of HSP70 as a chaperone for p53.

METHODS

Seventy-one patients with esophageal squamous cell carcinoma were admitted in the present study. Expression of HSP70 was analyzed by immunohistochemistry and correlated with TNM classification, vessel invasion, p53 expression, and clinical outcome after operation.

RESULTS

Overexpression of HSP70 was related to sex (p < 0.05), tumor configuration (p < 0.05), lymph node metastasis (p < 0.01), and lymphatic vessel invasion (p < 0.05). Expression of p53 and HSP70 were not correlated with each other (p = 0.824). Esophageal squamous cell carcinoma with HSP70 expression exhibited a significantly better prognosis compared with HSP70-negative esophageal squamous cell carcinoma in univariate analysis (p < 0.05), but no significance was found in multivariate analysis.

CONCLUSIONS

We suggest that HSP70 expression might be of use to assess the progression, lymph node metastasis, and lymphatic vessel invasion of esophageal squamous cell carcinoma. Inasmuch as both lymph node metastasis and HSP70 expression are prognostic variables in esophageal squamous cell carcinoma, examination of HSP70 expression may be of use to assess clinical outcome after operation.

Clinical significance of micrometastasis in lung and esophageal cancer: a new paradigm in thoracic oncology

In the past decade, detection of micrometastatic disease in different clinical samples including pleural lavage, lymph node, bone marrow, and blood has become a rapidly growing area of interest in research of non-small cell lung cancer and esophageal cancer. The results of these studies support the concept that, just as in many other solid malignancies, systemic spread may happen at an early stage in non-small cell lung cancer and esophageal cancer. Such systemic spread is often occult (micrometastases) at the time of primary diagnosis, which may have adverse effects on survival. Improved staging can be expected with information on micrometastases, and a subgroup of patients who will benefit most from adjuvant therapy might be identified. Although reliable and standard methods need to be developed before detection of micrometastasis is incorporated in the routine clinical practice, we suggest that it be considered an important correlate in clinical trials in non-small cell lung cancer and esophageal cancer.

Thoracoscopic and laparoscopic lymph node staging in esophageal cancer: do clinicopathological factors affect the outcome?

BACKGROUND

This study was performed to evaluate the pattern of lymphatic metastases found by combined thoracoscopic (TS) and laparoscopic (LS) lymph node staging in esophageal cancer, and ascertain whether clinicopathologic factors may be used to guide the clinical practice of combined TS and LS staging.

METHODS

A retrospective study was performed in a series of 76 esophageal cancer patients who had undergone both TS and LS staging before treatment. The correlation of TS and LS lymph node metastases with clinicopathologic factors was analyzed, including the clinical T stage, clinical N stage, tumor location, and histology.

RESULTS

Thirty-one patients (40.8%) were found to have lymphatic metastasis by TS and LS staging. Among them, 22 patients had abdominal lymph node metastases, 7 patients had mediastinal lymph node metastases, and 2 patients had both. Patients with advanced T stage (T3 to T4) or adenocarcinoma had a higher frequency of abdominal lymphatic metastases than patients with early T stage (T1 to T2) (39% vs 16%; p = 0.04) or squamous cell carcinoma (39% vs 20%; p = 0.079), respectively. Patients with clinical abdominal N1 stage had a higher incidence of positive laparoscopic finding than patients with clinical abdominal N0 stage (67% vs 23%; p = 0.001). There was no significant correlation between lymphatic metastases and the location of the primary tumor.

CONCLUSIONS

Clinicopathologic factors, including the histologic type, the clinical T stage, and abdominal N stage, may affect the outcome of TS and LS lymph node staging in esophageal cancer patients. This clinicopathologic impact may play a role for the selection of candidates for TS and LS staging, and also allows surgeons to focus their attention on the most likely high-yield biopsy targets.

CALGB 9380: a prospective trial of the feasibility of thoracoscopy/laparoscopy in staging esophageal cancer

BACKGROUND

The staging of esophageal cancer is imprecise. Thoracoscopic/laparoscopic (TS/LS) staging has been proposed as a more accurate lymph node (LN) staging method. We report the experience of an Intergroup NCI trial (CALGB 9380) evaluating the feasibility and accuracy of this staging modality.

PATIENTS AND METHODS

From February 1995 to September 1999, 134 patients were entered in the study. This study represents the analysis of final data on 113 patients. TS/LS was considered feasible if TS and 1 LN sampled at least 3 LN by LS; a confirmed positive node was found; or T4 or M1 disease was documented. If this was accomplished in more than 70% of patients, TS/LS was believed to be feasible.

RESULTS

The LN stations most frequently sampled in the thorax (134 patients) were levels 2 (33%), 3 (38%), 4 (40%), 7 (76%), 8 (69%), 9 (55%), and 10 (43%) and in the abdomen levels 17 (70%) and 20 (55%). The frequency of positive LN by level were as follows: 2 (10%), 3 (8%), 4 (10%), 7 (10%), 8 (25%), 9 (10%), 10 (10%), 17 (34%), and 20 (27%). Noninvasive tests (computed tomographic scan, magnetic resonance imaging, esophageal ultrasound scan) each incorrectly identified TN staging as noted by missed positive or false-negative LN or metastatic disease found at TS/LS staging in 50%, 40%, and 30% of patients, respectively. Median operating time was 210 minutes (range, 40 to 865 minutes). Median postoperative hospital stay was 3 days (range, 1 to 35 days). There were no deaths or major complications. Seventy-three percent of patients met the definition for feasibility. In 30 patients TS was not feasible. Positive LN disease was found in 43 patients; 32 were deemed N0. Ten patients had T4/M1 disease. Of the 32 potentially resectable N0 patients, 14 patients had preoperative induction therapy; 13 patients went directly to operation with N0 confirmed in 9 patients, NX in 1 and N1 in 3. Three patients were unresectable, 1 patient died, and 1 was lost to follow-up.

CONCLUSIONS

In summary, the feasibility of TS/LS was confirmed. It doubled the number of positive LNs identified by conventional, noninvasive staging. The overall accuracy remains to be defined by analysis of the LN negative group in follow-up. Although the positive predictive value was high, further study is warranted to confirm the role of TS/LS in the staging algorithm of esophageal cancer.

Thoracoscopic and laparoscopic staging for esophageal cancer

Accurate pretreatment staging for patients with esophageal cancer (EC) is becoming increasingly important in the evaluation and comparison of different treatment modalities. Noninvasive staging methods are imperfect in detecting lymph node metastasis in patients with EC. Surgical staging with the thoracoscopic/laparoscopic (Ts/Ls) technique may provide accurate staging information that is useful for evaluating and comparing the results of clinical trials of preoperative chemotherapy and radiotherapy. It can be used to confirm or exclude suspicious distant metastasis found by other staging methods. Pretreatment (lymph node) biopsies obtained by Ts/Ls staging allow further molecular biologic analysis to detect occult lymph node metastasis for more accurate lymph node staging. Since 1992, we have used Ts/Ls staging for EC in 111 patients. We found that Ts/Ls is a promising method for staging lymph nodes in EC patients. A recent study showed that pretreatment surgical lymph node staging can predict response and survival for EC patients receiving trimodality treatment (ie, radiation, chemotherapy, and surgery). The information obtained with surgical staging now offers us the opportunity to optimize therapy to specific patient groups based on the extent of disease at the time of initial presentation. Nevertheless, unlike the practice of mediastinoscopy in lung cancer patients, Ts/Ls staging in EC patients remains an academic interest rather than a clinical practice. The concept of accurate pretreatment staging of EC remains to be realized and accepted in the clinical community.

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.

Use of minimally invasive surgery in staging esophageal cancer

Noninvasive staging of esophageal cancer (EC) is often inaccurate, and this fact has compromised clinical trials of treatment for EC. Prognostic evaluation might allocate chemotherapy and radiation more appropriately. Thoracoscopy and laparoscopy has recently shown promising results, and molecular analysis of the recovered tissue may further improve staging accuracy.