Clinical results of transhiatal esophagectomy for carcinoma of the lower thoracic esophagus according to biological markers

Prognostic and Clinicopathological Significance of Epidermal Growth Factor Receptor (EGFR) Expression in Oral Squamous Cell Carcinoma: Systematic Review and Meta-Analysis

The aim of this systematic review and meta-analysis was to evaluate the current evidence in relation to the clinicopathological and prognostic significance of epidermal growth factor receptor (EGFR) overexpression in patients with oral squamous cell carcinoma (OSCC). We searched MEDLINE/PubMed, Embase, Web of Science, and Scopus for studies published before November 2022. We evaluated the quality of primary-level studies using the QUIPS tool, conducted meta-analyses, examined inter-study heterogeneity via subgroup analyses and meta-regressions, and performed small-study effects analyses. Fifty primary-level studies (4631 patients) met the inclusion criteria. EGFR overexpression was significantly associated with poor overall survival (hazard ratio [HR] = 1.38, 95% confidence intervals [CI] = 1.06-1.79, p = 0.02), N+ status (odds ratio [OR] = 1.37, 95%CI = 1.01-1.86, p = 0.04), and moderately-poorly differentiated OSCC (OR = 1.43, 95% CI = 1.05-1.94, p = 0.02). In addition, better results were obtained by the application of a cutoff point ≥10% tumor cells with EGFR overexpression (p < 0.001). In conclusion, our systematic review and meta-analysis supports that the immunohistochemical assessment of EGFR overexpression may be useful as a prognostic biomarker for OSCC.

Radiochemotherapy with or without cetuximab for unresectable esophageal cancer: final results of a randomized phase 2 trial (LEOPARD-2)

Purpose

To investigate the efficacy and toxicity of cetuximab when added to radiochemotherapy for unresectable esophageal cancer.

Methods

This randomized phase 2 trial (clinicaltrials.gov, identifier NCT01787006) compared radiochemotherapy plus cetuximab (arm A) to radiochemotherapy (arm B) for unresectable esophageal cancer. Primary objective was 2‑year overall survival (OS). Arm A was considered insufficiently active if 2‑year OS was ≤40% (null hypothesis = H₀), and promising if the lower limit of the 95% confidence interval was >45%. If that lower limit was >40%, H₀ was rejected. Secondary objectives included progression-free survival (PFS), locoregional control (LC), metastases-free survival (MFS), response, and toxicity. The study was terminated early after 74 patients; 68 patients were evaluable.

Results

Two-year OS was 71% in arm A (95% CI: 55–87%) vs. 53% in arm B (95% CI: 36–71%); H₀ was rejected. Median OS was 49.1 vs. 24.1 months (p = 0.147). Hazard ratio (HR) for death was 0.60 (95% CI: 0.30–1.21). At 2 years, PFS was 56% vs. 44%, LC 84% vs. 72%, and MFS 74% vs. 54%. HRs were 0.51 (0.25–1.04) for progression, 0.43 (0.13–1.40) for locoregional failure, and 0.43 (0.17–1.05) for distant metastasis. Overall response was 81% vs. 69% (p = 0.262). Twenty-six and 27 patients, respectively, experienced at least one toxicity grade ≥3 (p = 0.573). A significant difference was found for grade ≥3 allergic reactions (12.5% vs. 0%, p = 0.044).

Conclusion

Given the limitations of this trial, radiochemotherapy plus cetuximab was feasible. There was a trend towards improved PFS and MFS. Larger studies are required to better define the role of cetuximab for unresectable esophageal cancer.

Esophageal Cancer: Associated Factors with Special Reference to the Kashmir Valley

Esophageal cancer is one of the most common cancers worldwide. It is a multifactorial disease, and no single agent has been identified so far as the sole cause of the cancer. Many factors like smoking, the consumption of alcohol, fungal-contaminated, spicy and various nitrosamine-containing food stuffs and hot beverages, nutritional deficiency of some vitamins like β-carotene, vitamin A, C and E and minerals like zinc, selenium and molybdenum, the use of opium, HPV infection and various genetic factors have been found associated with the occurrence of the disease worldwide. Wide geographic differences and substantial changes in the incidence of esophageal cancer occurring over time have been suggested. Among the risk factors in India, betel quid chewing carries a relatively high risk. High incidences in Kashmir have been associated with the consumption of hot salted tea, sun-dried, smoked foods, tobacco in the form of hukka and various genetic factors. The exact cause of esophageal squamous cell carcinoma is unknown. Much work has been carried out on the role of various environmental factors, gene mutations, and polymorphisms worldwide, including Kashmir. Although the Kashmir valley is present on the border of the ‘high risk esophageal cancer belt’ and esophageal squamous cell carcinoma represents the most commonly occurring malignancy in Kashmir, the amount of information available on various associated factors is still very little as there is a paucity of various epidemiological and molecular studies being carried out in this field.

Genetic variants of EGF and VEGF predict prognosis of patients with advanced esophageal squamous cell carcinoma

PURPOSE

To investigate the association between genetic polymorphisms of growth factor-related genes and prognosis in patients with advanced esophageal squamous cell carcinoma (ESCC).

PATIENTS AND METHODS

A total of 334 ESCC patients with advanced tumor stages (stages IIB, III and IV) were enrolled in the study. The genotypes of 14 candidate single nucleotide polymorphisms (SNPs) involved in growth factor-related functions were analyzed using iPLEX Gold technology from the genomic DNA of peripheral leukocytes, and were correlated with the clinical outcome of patients. Serum levels of growth factors were examined by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The genetic polymorphisms of EGF:rs4444903, EGF:rs2237051 and VEGF:rs2010963 showed significant associations with overall survival (OS) of advanced ESCC patients (A/A+ A/G vs. GG, [HR = 0.77, 95% CI = 0.60-0.99, P = 0.039 for rs4444903; A/G+ G/G vs. A/A, [HR = 0.74, 95% CI = 0.58-0.95, P = 0.019 for rs2237051; G/G+G/C vs. C/C, [HR] inves = 0.69, 95% CI = 0.50-0.95, P = 0.023 for rs2010963). EGFR:rs2227983 and 3 SNPs of PIK3CA also showed borderline significant correlation with OS of advanced ESCC patients (P = 0.058 for rs2227983; P = 0.069, 0.091 and 0.067 for rs6443624, rs7651265 and rs7621329 of PIK3CA respectively). According to cumulative effect analysis of multiple SNPs, patients carrying 4 unfavorable genotypes exhibited more than a 3-fold increased risk of mortality. Finally, both EGF and VEGF expression levels significantly associated with patient mortality.

CONCLUSION

The genetic variants and expression levels of EGF and VEGF can serve as prognostic predictors in patients with advanced ESCC, and thus provide more information for optimizing personalized therapies for patients with ESCC.

A phase I pharmacologic study of necitumumab (IMC-11F8), a fully human IgG1 monoclonal antibody directed against EGFR in patients with advanced solid malignancies

PURPOSE

This study aimed to determine a maximum tolerated dose (MTD) and recommended dose for disease-directed studies of necitumumab (IMC-11F8), a fully human IgG(1) monoclonal antibody directed at the epidermal growth factor receptor, and to characterize the safety profile, pharmacokinetics, preliminary antitumor activity, and immunogenicity of necitumumab.

EXPERIMENTAL DESIGN

Patients with advanced solid malignancies were treated with 100 to 1,000 mg (flat dosing) necitumumab followed by a 2-week pharmacokinetics sampling period, before beginning 6-week cycles of therapy.

RESULTS

Sixty patients received necitumumab weekly (29 patients) or every other week (31 patients). Two patients receiving 1,000 mg every 2 weeks experienced dose-limiting toxicities (DLT; grade 3 headache), accompanied by grade 3 nausea and vomiting in one patient. Occurring hours after the initial dose, these DLTs established 800 mg as the MTD. Mild dose-related skin toxicity was the most common drug-related toxicity (80%). One patient in each arm experienced grade 3 acneform rash, which responded to oral antibiotics and topical therapy. Toxicity was similar on both schedules. Necitumumab exhibited saturable elimination and nonlinear pharmacokinetics. At 800 mg (both arms), its half-life was approximately 7 days. All patients treated with >or=600 mg necitumumab achieved target trough concentrations (>or=40 microg/mL). Antibodies against necitumumab were not detected. Partial response and stable disease were experienced by 2 and 16 patients, respectively.

CONCLUSION

Well tolerated, necitumumab is associated with preliminary evidence of antitumor activity, and achieves biologically relevant concentrations throughout the dosing period. The recommended dose of necitumumab for further clinical development is 800 mg (flat dose) weekly or every 2 weeks based on the clinical setting.

Aberrant promoter methylation of the TPEF gene in esophageal squamous cell carcinoma

Aberrant methylation of tumor suppressor genes plays an important role in the development of esophageal squamous cell carcinoma (ESCC). The purpose of the present study was to identify the epigenetic changes in ESCC. Methylation-sensitive arbitrarily primed polymerase chain reaction (MS AP-PCR) analysis was used on 22 matched ESCC tumors and adjacent normal tissues. Through this screen we identified a frequently methylated fragment that showed a high homology to the 5'-CpG island of the gene encoding a transmembrane protein containing epidermal growth factor and follistatin domains (TPEF). The methylation status of the TPEF gene was then detected by bisulfite sequencing and the levels of TPEF mRNA were detected by RT-PCR. In addition, the effects of a methylation inhibitor 5-aza-2'-deoxycytidine on TPEF mRNA expression was determined in cells of ESCC cell lines. Hypermethylation of the 5'-CpG island of TPEF was found in 12 of 22 (54.5%) primary tumors. Reverse transcription PCR analysis demonstrated that TPEF mRNA expression was significantly lower in tumors than in adjacent normal tissues, which is associated with promoter hypermethylation. In addition, treatment of ESCC cell lines with 5-aza-2'-deoxycytidine led to re-expression of the TPEF transcript. In conclusion, we observed promoter of TPEF gene is frequently hpermethylated, and is associated with the loss of TPEF mRNA expression in ESCC samples. Promoter hypermethylation of TPEF gene may play a role in the development of ESCC.

Interaction of MT1-MMP and laminin-5gamma2 chain correlates with metastasis and invasiveness in human esophageal squamous cell carcinoma

To gain insights into metastatic mechanisms in esophageal squamous cell carcinoma (ESCC), we established sublines (MLuB1 and MLuC1) with different capacity of spontaneous lung metastasis by subcutaneous injection of a human ESCC cell line (EC 9706) into nude mices. The incidence of the mice with lung metastasis produced by MLuC1 (87%) was significantly higher than that of MLuB1 (22%). The gene expression profiles of the two sublines were compared with cDNA arrays containing 5,000 known genes, and 47 genes were differentially expressed > or =2.0 fold. Laminin-5gamma2 chain (Ln-5gamma2) was one of the up-regulated genes in MLuC1 cells. Proteolytically processed forms of gamma2 are known to promote migration of a multitude of epithelial cells in vitro. Western-blotting analysis revealed that degraded fragments of Ln-5gamma2 and active form of membrane-type matrix metalloproteinase-1 (MT1-MMP) in MLuC1 was significantly higher than those in MLuB1. Expression of MT1-MMP was observed in 60 of 75 Ln-5gamma2-positive carcinoma tissues (80%). Co-expression of the two proteins was significantly associated with depth of invasion (P = 0.012). Moreover, proteolytic fragments of Ln-5gamma2 and active forms of MT1-MMP were frequently found in tumor tissues, whereas in the corresponding normal esophageal tissues there were only intact forms of gamma2 and MT1-MMP. siRNA-mediated silencing of MT1-MMP significantly reduced production of gamma2' and gamma2x in MLuC1 cells and inhibited cell migration. The results suggest that MT1-MMP is an enzyme responsible for Ln-5gamma2 cleavage in ESCC, and interaction between them may play a critical role in promoting invasion and metastasis of human ESCC.

Novel therapies targeting signaling pathways in lung cancer

Despite advances in chemotherapy, the prognosis for advanced non-small-cell lung cancer (NSCLC) remains dismal. Increasing understanding of the biological processes responsible for lung carcinogenesis has led to development of new therapeutic strategies targeting this disease at a molecular level. This article examines the molecular events believed to lead to cellular changes in lung cancer, and how knowledge of these is used to develop new agents used individually or in combination with available cytotoxic drugs to improve survival. Finally, it explores how a deeper understanding of the embryonic signaling pathways responsible for airway epithelial repair and tumorogenesis, such as Hedgehog (Hh), Notch, and Wingless (Wnt), can lead to the development of newer and more specific therapies for lung cancer.

Regulation of MAPKs by growth factors and receptor tyrosine kinases

Multiple growth- and differentiation-inducing polypeptide factors bind to and activate transmembrane receptors tyrosine kinases (RTKs), to instigate a plethora of biochemical cascades culminating in regulation of cell fate. We concentrate on the four linear mitogen-activated protein kinase (MAPK) cascades, and highlight organizational and functional features relevant to their action downstream to RTKs. Two cellular outcomes of growth factor action, namely proliferation and migration, are critically regulated by MAPKs and we detail the underlying molecular mechanisms. Hyperactivation of MAPKs, primarily the Erk pathway, is a landmark of cancer. We describe the many links of MAPKs to tumor biology and review studies that identified machineries permitting prolongation of MAPK signaling. Models attributing signal integration to both phosphorylation of MAPK substrates and to MAPK-regulated gene expression may shed light on the remarkably diversified functions of MAPKs acting downstream to activated RTKs.

Cancer of the Gastroesophageal Junction: Combined Modality Therapy

Esophageal cancer, an uncommon, but highly virulent malignancy in the United States, will be responsible for nearly 14,000 deaths in the year 2005. The prognosis for patients who have adenocarcinoma of the distal esophagus and gastroesophageal junction and who are treated with the standard approaches of surgery or combined chemoradiation therapy is poor. Recent clinical trials have evaluated the use of preoperative chemotherapy followed by surgery, combined concurrent preoperative chemoradiotherapy followed by surgery, or definitive chemoradiotherapy alone without surgery. This article focuses on recent advances in the use of combined modality therapy in adenocarcinoma of the esophagus and gastroesophageal junction.

Cancer of the gastroesophageal junction: Current therapy options

Active chemotherapy agents in metastatic adenocarcinoma of the esophagus include taxanes (docetaxel or paclitaxel), 5-fluorouracil, irinotecan, platinum drugs (including cisplatin, oxaliplatin, and carboplatin), and anthracyclines. Conventional chemotherapy combines infusional 5-fluorouracil with cisplatin. The addition of a third drug to this backbone results in greater toxicity and only marginal improvements in outcome. Alternative and potentially better-tolerated chemotherapy involves two-drug regimens, combining 5-fluorouracil with a taxane or irinotecan, or combining a platinum drug with irinotecan or a taxane. Although preoperative chemotherapy improves survival compared with surgery alone, the addition of radiation therapy to chemotherapy preoperatively improves rates of curative resection, reduces local tumor recurrence, and achieves a significant rate of pathologic complete response. Combined preoperative chemotherapy and concurrent radiotherapy is the preferred preoperative strategy for locally advanced adenocarcinoma of the esophagus. Survival is improved with postoperative chemotherapy and radiotherapy if none has been delivered preoperatively.

EGF-ERBB signalling: towards the systems level

Signalling through the ERBB/HER receptors is intricately involved in human cancer and already serves as a target for several cancer drugs. Because of its inherent complexity, it is useful to envision ERBB signalling as a bow-tie-configured, evolvable network, which shares modularity, redundancy and control circuits with robust biological and engineered systems. Because network fragility is an inevitable trade-off of robustness, systems-level understanding is expected to generate therapeutic opportunities to intercept aberrant network activation.

Epidermal growth factor receptor mutations in non-small cell lung cancer: a basic science discovery with immediate clinical impact

A large body of preclinical work suggested that the epidermal growth factor receptor (EGFR) would be a successful target for therapy against non-small cell lung cancer (NSCLC), and this led to the development of oral, selective EGFR tyrosine kinase inhibitors (TKI) that improve symptoms and survival in patients with advanced NSCLC. However, not all patients benefit from this treatment, and there has been great interest in identifying the molecular correlates that predict for response to these agents. The recent detection of somatic mutations in EGFR that predict for response to the EGFR tyrosine kinase inhibitors has excited the scientific community. This discovery has far-reaching implications, not only for lung cancer patients treated with an EGFR TKI but also for future drug development in all malignancies.

Targeted therapies for esophageal cancer

Esophageal cancer is a highly aggressive neoplasm. In 2005, 14,520 Americans will be diagnosed with esophageal cancer, and more than 90% will die of their disease. On a global basis, cancer of the esophagus is the sixth leading cause of cancer death worldwide. In fact, gastric and esophageal cancers together accounted for nearly 1.3 million new cases and 980,000 deaths worldwide in 2000-more than lung, breast, or colorectal cancer. Although esophageal squamous cell carcinoma cases have steadily declined, the incidence of gastroesophageal junction adenocarcinoma has increased 4%-10% per year among U.S. men since 1976, more rapidly than for any other cancer type, and parallels rises in population trends in obesity and reflux disease. With advances in surgical techniques and treatment, the prognosis of esophageal cancer has slowly improved over the past three decades. However, the 5-year overall survival rate (14%) remains poor, even in comparison with the dismal survival rates (4%) from the 1970s. The underlying reasons for this disappointingly low survival rate are multifold: (a) ineffective screening tools and guidelines; (b) cancer detection at an advanced stage, with over 50% of patients with unresectable disease or distant metastasis at presentation; (c) high risk for recurrent disease after esophagectomy or definitive chemoradiotherapy; (d) unreliable noninvasive tools to measure complete response to chemoradiotherapy; and (e) limited survival achieved with palliative chemotherapy alone for patients with metastatic or unresectable disease. Clearly, additional strategies are needed to detect esophageal cancer earlier and to improve our systemic treatment options. Over the past decade, the field of drug development has been transformed with the identification of and ability to direct treatment at specific molecular targets. This review focuses on novel targeted treatments in development for esophageal squamous cell carcinoma and distal esophageal and gastroesophageal junction adenocarcinoma.

Correlation between laminin-5 gamma2 chain and epidermal growth factor receptor expression in esophageal squamous cell carcinomas

OBJECTIVES

Laminin-5 gamma2 chain (LN-5 gamma2) is an extracellular matrix protein that plays an important role in cell migration and tumor invasion. We evaluated the association of LN-5 gamma2 and epidermal growth factor receptor (EGFR) expression in esophageal squamous cell carcinoma (SCC).

METHODS

LN-5 gamma2 and EGFR expression was evaluated in 110 esophageal SCC patients by immunohistochemistry, and was confirmed using esophageal SCC cell lines by Western blot analysis.

RESULTS

LN-5 gamma2 expression in the invasive front of the tumor was correlated with the depth of invasion (p = 0.0001), lymph node metastasis (p = 0.0011) and pathological stage (p = 0.0001). The strong expression of EGFR was also correlated with lymph node metastasis (p = 0.0456) and the pathological stage (p = 0.0055). In patient survival, LN-5 gamma2 positivity and/or strong EGFR expression showed a significantly low survival rate as compared with those with lesser expression of LN-5 gamma2 and EGFR. Immunohistochemically, LN-5 gamma2 expression was significantly correlated with EGFR expression (p < 0.0001). Western blot analysis also confirmed the correlated expression of LN-5 gamma2 and EGFR in SCC cell lines except 2 of the 5 cell lines.

CONCLUSIONS

This study suggests that coexpression of LN-5 gamma2 and EGFR is closely related to the progression and poor prognosis of esophageal SCC.

The impact of EGFR mutations on gefitinib sensitivity in non-small cell lung cancer

Gefitinib (ZD1839, Iressa®; AstraZeneca) has produced objective tumor responses and symptom improvement in some patients with non-small cell lung cancer. In clinical trials, 12–18.4% of patients had a rapid and often dramatic clinical response, and a subset analysis of the Iressa Dose Evaluation in Advanced Lung Cancer (IDEAL)-1 and -2 trials demonstrated that female gender and adenocarcinoma were associated with a higher response to gefitinib. However, analysis from clinical trials have not found a relationship between epidermal growth factor receptor (EGFR) expression and response in patients receiving gefitinib. Recently, three studies have identified mutations affecting the EGFR in lung cancer from patients who respond to gefitinib. EGFR gene mutations were common in lung cancer from ’never smokers’ and were associated with sensitivity of tumors to gefitinib. Furthermore, it has been reported that the phosphatidylinositol 3-kinase/Akt signaling pathway plays a critical role in the antitumor effects of gefitinib. Although EGFR mutations do not fully explain the clinical benefit, the data regarding EGFR mutations may help to define the patient population that will most likely benefit from EGFR tyrosine-kinase-targeted therapies.

The role of receptor tyrosine kinase inhibition in treating gastrointestinal malignancy

Tyrosine kinase receptors are proteins that transduce the signal from many growth factor and cytokine ligands to produce intracellular responses. As such they can activate multiple signalling cascade pathways and influence cell division, migration and survival. Many show upregulation in certain malignancies, including those of the gastrointestinal tract, and are thought to play key roles in carcinogenesis. This makes them attractive targets for drug therapy and in recent years many inhibitors have been developed. This review discusses the current situation regarding the development of inhibitors with particular reference to the erbB family, the insulin-like growth factor receptor, the Met receptor, the receptor for vascular endothelial growth factor and the Kit receptor. The evidence will be related back to cancers of the gut lumen. Clinical effectiveness in this area seems to lie in using a combinatorial approach that inhibits multiple key signalling points, and the reasons for this will be discussed.

Biologic approaches to the treatment of gastrointestinal malignancy

Though new agents have recently been approved for the treatment of gastrointestinal malignancies, cure rates remain low and survival times of patients short. Because of these discouraging numbers, there is a vigorous search for new agents and new strategies. This article reviews some of these strategies and the status of agents in clinical development. Though an exhaustive search is impossible and the field is changing so rapidly, the agents selected here for discussion may be considered representative of others. Discussed here are agents targeting the vascular endothelial growth factor as an example of an angiogenesis inhibitor, and agents targeting the epidermal growth factor receptor, the ras oncogene, and the immune system.

EGFR and cancer prognosis

Elevated levels of the epidermal growth factor receptor (EGFR), a growth-factor-receptor tyrosine kinase, and/or its cognate ligands have been identified as a common component of multiple cancer types and appear to promote solid tumour growth. This article examines the relationship between EGFR expression and cancer prognosis based on literature compiled on PubMed between 1985 and September 2000. More than 200 studies were identified that analysed relapse-free-interval or survival data directly in relation to EGFR levels in over 20000 patients. Analysis of the data showed that 10 cancer types both express elevated levels of EGFR relative to normal tissues and have been studied in sufficient depth to allow sound judgements to be made concerning the association between EGFR and patient outlook. The EGFR was found to act as a strong prognostic indicator in head and neck, ovarian, cervical, bladder and oesophageal cancers. In these cancers, increased EGFR expression was associated with reduced recurrence-free or overall survival rates in 70% (52/74) of studies. In gastric, breast, endometrial and colorectal cancers, the EGFR provided more modest prognostic information, correlating to poor survival rates in 52% (13/25) of studies, while in non-small cell lung cancer (NSCLC), EGFR expression only rarely (3/10 studies) related to patient outlook. However, it is likely that the true prognostic significance of the EGFR has been underestimated as the published studies only assessed total cellular EGFR levels, rather than the activated form of the receptor, and were not standardised with regard to patient populations or assay methods. Finally, it is important to stress that failure to detect a prognostic significance for EGFR in any one cancer type does not necessarily preclude patients from benefiting from anti-EGFR therapies.

Significance of lymph node dissection of the superior mediastinal region in esophageal cancer patients

The effect of the superior mediastinal lymph node dissection was compared retrospectively with that of standard dissection in 108 esophageal cancer patients. Five-year survival rates were 46.3% in patients who underwent standard surgery (group A) and 39.3% in patients who underwent superior mediastinal lymph node dissection (group B). The survival curves were basically the same. Nineteen out of 42 (45.2%) tumors in group A and 24 out of 66 (36.4%) tumors in group B recurred. The distribution of the first sites of recurrence did not differ significantly between groups. However, 14 tumors (67%) in group A recurred in the lymph nodes, but only seven tumors recurred (28%) in the lymph nodes in group B. Eleven tumors (52%) in group A recurred to superior mediastinal nodes, but only one tumor (4%) recurred to a superior mediastinal node in group B. Fourteen of the group B patients showed metastasis to superior mediastinal lymph nodes and none of these patients survived for more than 5 years. Eleven of these 14 patients showed metastasis to only one or two nodes. Based on our data and other reported findings, we conclude that extended lymphadenectomy of the superior mediastinal region alone does not contribute to improved survival of esophageal cancer patients, but it does contribute to the prevention of lymph node recurrence in this region.

Risk factor analysis of post-operative mortality in oesophagectomy

Oesophagectomy for cancer is associated with a significant incidence of post-operative complications and death, and so this study sought to determine objective criteria which could better predict operative risk. Clinical risk factors for oesophagectomy and the results of objective investigations were assessed prospectively by independent surgical and intensive care specialists and a multivariate analysis was used to develop a scoring system for predicting operative risk. From September 1994 to June 1997, 32 patients from an overall experience of 70 oesophagectomy procedures for cancer at the Royal Adelaide Hospital were entered into this study. Hypertension, a history of previous cigarette smoking and FEV1/FVC were identified as independent predictors of the post-operative outcome. Age and FEV1/FVC were also significantly associated with the occurrence of cardiovascular and pulmonary complications respectively. The average risk score was 4.8 +/- 4.5 (mean +/- SD) for patients who died, 2.9 +/- 2.9 for patients who developed post-operative complications and 2.6 +/- 2.1 for patients who had an uncomplicated recovery. The likelihood of post-operative mortality and morbidity was highest in patients with a score of 5 or more. Mortality rates of different patient groups undergoing oesophagectomy by the same surgeons during the same time period were also compared, showing greatly different mortality rates. Important risk factors can be identified preoperatively, and a scoring system can be used to provide objective criteria which can be used to identify patients at an increased risk of post-operative complications and death. A prospective study of this scoring system is now needed to determine whether it proves useful in rejecting patients for surgery who would otherwise have undergone oesophagectomy.

Molecular biology of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is the predominant histologic subtype of esophageal cancer and characterized by high mortality rate and geographic differences in incidence. With the advances in the field of molecular biology, our understanding of the pathogenesis, epidemiology and behavior of ESCC continues to evolve. The recent development includes research in etiopathogenesis (viruses and cancer susceptibility genes), keratins, tumor related genes (oncogenes, tumor suppressor genes, genes involved in metastasis and apoptosis genes), proliferation-related factors (nuclear proteins, flow cytometry/morphometry, argyrophilic nucleolar organizer region) and factors related to metastases (cell adhesion molecules and enzymes related to degradation of extracellular matrix). There are ranges of molecular techniques potentially available to complement the traditional approaches in the management of ESCC. On the other hand, critics are needed in the interpretation and translation of these research findings from laboratories to clinics. Further investigations, education and collaborations between the various scientific and clinical disciplines are important to successful application of these molecular findings aiming at improving management of patients with ESCC.