The following are a few newer publications that I found useful when I looked for what’s new with esophageal cancer.
- The Shanxi province, a region in north-central China, has some of the highest esophageal cancer rates in the world. Ref. 4 studied precursor lesions and early cancer lesions and did genetic studies in collaboration with the National Cancer Institute, Bethesda/ Md (US). The findings showed that four genetic markers were associated with the initiation of cancer. Loss of “heterogeneity” at these loci was thought to cause initiation and progression of esophageal cancer. There were eight other genetic loci that were found to be associated with dysplasia and overt cancer. Loss of heterogeneity in these loci was thought to be associated with the later stages of the cancer forming process. These findings likely will lead to further knowledge about how to diagnose esophageal cancer earlier and how to prevent it from happening in the first place.
- Infiltrating cytotoxic T lymphocytes were investigated in Ref. 5. It was found that a subclass of T-lymphocytes, the CD8(+) T cells, when they infiltrated the esophageal tumor specimen, were associated with a much better outcome. The authors felt that this finding will have diagnostic and therapeutic implications in the future.
- Duke’s classification is used for staging in colorectal cancer. Ref. 6 is suggesting for the first time that this classification would be useful also for classification of esophageal cancers. Here are the survival data, based on 251 patients between 1981 to 1999, which I arranged as a table for easy comparison with the survival data above. This group of patients had histologically verified squamous cell esophageal cancer, which excluded the adenomatous esophageal cancer types, who have a worse outcome. The authors found that this Dukes’ classification, when compared to other classification systems, had a good correlation with the tumor size, the clinical course and the outcome in all the other similar staging procedures. With its simplicity of staging they felt that this would be a good staging system to use.
5-year survival rates for thoracic squamous cell esophageal cancer
Treatment with esophagectomy
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Stage (Duke)
A : 94 %
B : 75 %
C : 43 %
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- Here is a study that was designed to investigate whether or not the rate of esophageal cancer was different for surgical or medical control of reflux esophagitis. The authors of Ref. 7 did this longterm control of gastroesophageal reflux disease(=GERD) study and recalled 239 patients who either were treated medically or surgically 9 to 10 years earlier. They were examined by gastroscopy and the following findings were obtained: both the rate of lower esophagitis as well as the rate of esophagus cancer was identical in both groups. The group that was in the past treated with fundoplication in the lower esophagus still needed anti-reflux medication in 62%. The medically controlled group needed anti-reflux medication in 92%.The annual esophageal adenocancer rate was 0.07% for patients with only GERD at the outset. With Barrett esophagitis at the outset the annual cancer rate was higher at 0.4%. These cancer rates were identical for both groups, with or without surgery. The authors concluded that surgery for GERD or Barretts esophagitis would not be indicated. The mortality rate was actually higher in the surgical group because of unrelated cardiac disease. Anti-acid medication is needed regardless of the decision to do ant-reflux surgery or not. This finding is interesting as it dispels the myth that has been taught to generations of medical students that anti-reflux surgery at the lower esophagus would prevent development of esophageal cancer later in life. What makes a difference is the use of a proton pump inhibitor or the use of Zantac.
Summary regarding esophageal cancer
Esophageal cancer is a difficult cancer for physicians to diagnose and treat early as it is asymptomatic in the beginning and due to its high vascularity metastasizes early. It is prudent for everybody to screen what we eat, as sodium nitrite and sodium nitrates are still popular curing agents for meat and meat products. These carcinogens make meat look red for a long time.
However, checking food labels for the small print as mentioned above in the “esophageal cancer prevention ” box will pay handsome dividends for your health on the longterm. Also keep in mind that cigarettes and hard liquor are not part of a healthy diet. With regard to alcohol it is a matter of concentration and exposure over the years that decides when the lining of the esophagus will turn into cancer cells. With regard to carcinogens from cigarettes it is the effect of swallowed carcinogens that stimulates cancer transformation of the cells of the lining of the esophagus. Both effects are superadditive and you may want to give these life style aspects some thought and ,if necessary in your situation make appropriate changes. This is much easier than facing the shock of a sudden cancerous disease in the esophagus and the precarious road of treatment mentioned above.
References:
1. Cancer: Principles &Practice of Oncology.4th edition. Edited by Vincent T. DeVita, Jr. et al. Lippincott, Philadelphia,PA, 1993. Chapter 25. Cancer of the esophagus.
2. Cancer: Principles&Practice of Oncology. 5th edition, volume 1. Edited by Vincent T. DeVita, Jr. et al. Lippincott-Raven Publ., Philadelphia,PA, 1997. Cancer of the esophagus.
3. D Sharma J Indian Med Assoc 1999 Sep;97(9): 360-364.
4. MJ Roth et al. Cancer Res 2001 May 15;61(10):4098-4104.
5. K Schumacher et al. Cancer Res 2001 May 15;61(10):3932-3936.
6. M Tachibana et al. Virchows Arch 2001 Apr;438(4):350-356.
7. SJ Spechler et al. JAMA 2001 May 9;285(18):2331-2338.
