Globally, gastric cancer ranks fourth and fifth for males and females respectively in terms of the incidence rate, and ranks third and fifth for males and females respectively in terms of the mortality rate.(1) In Korea, gastric cancer deaths rank third among total cancer deaths, and the number of deaths from stomach cancer is almost the same as that from cardiovascular diseases.(2) Korea is classified as a high incidence area for gastric cancer. Stomach cancer has the highest incidence and is the third leading cause of death among other cancers in males, and has the third highest incidence and is the second leading cause of death in females.(2) The highest incidence of gastric cancer is in the 70's patient age group,(2) being considered as one of the diseases associated with aging.

The average life expectancy in Korean population has been growing and in the year 2000 it was projected to reach 76 years according to the statistics released by the Korean government. The age group with the highest incidence has also increased from 50's to 60's in 1995,(3) to 70's in 2000 as mentioned above. Older gastric cancer patients usually have worse physical status than the younger stomach cancer patients,(4) and have accompanying diseases that often force them to have an aversion to surgical treatments.

We conducted a survey on the survival rate of gastric cancer patients and based on the survey, we investigated the items for consideration in the older age group of stomach cancer patients in comparison with the younger age group of stomach cancer patients.

A total of 1,738 patients who were diagnosed with gastric cancer and who underwent surgery at the Korea University Guro Hospital between January 1996 and December 2005 were selected and then, 45 patients who underwent simple laparotomy only, and 61 patients who underwent gastroenterostomy only were excluded leaving 1,632 patients to participate in the survey. These 1,632 patients' ages ranged from 23 to 86 years and comprised of 113 patients in their 40's or younger, 1,270 patients between 41 and 69 years, and 249 patients in their 70's or older.

Patients aged 41 to 69 years were categorized as the younger age group and patients aged 70 years or older were categorized as the older age group and finally the survey was conducted in a total of 1,519 patients. The purpose of the study was to compare the results in the younger age group with those in the older age group. Patients in their 70's or older who had an average postoperative life expectancy of 5 years were classified as the older age group based on the median life expectancy of 76 years as of 2000 released by the Korean government in 2005. In addition, gastric cancer patients in their 40's or younger were excluded from the present study because they were considered to show different disease progression than that seen in the age group with the highest incidence.(4)

A comparative analysis of the two groups in terms of sex, postoperative hospital stay, American Society of Anesthesiologists (ASA) risk physical status, accompanying diseases, postoperative T stage and N stage was conducted. The ASA risk physical status is not only a standard for assessing preoperative physical status but it is also an important indicator predicting postoperative deaths or development of complications. In the present study, preoperative evaluation performed by an anesthesiologist was used for analysis. In addition, postoperative complications which developed during the hospital stay were investigated. Complication was defined as an event which required an additional procedure or administration of drugs with prolonged hospital stay, and which was in accordance with the confirmation based on clinical findings and radiologic results. Complications were retrospectively investigated based on the medical records. Surgical complications included postoperative bleeding, necrosis or stenosis of anastomotic site, peritonitis, wound infection and bile leakage associated with surgery. Medical complications included diseases such as pneumonia, myocardiac infaction, severe arrhythmia, liver dysfunction, acute kidney dysfunction and thrombosis which required administration of additional drugs.

For cancer staging, TNM stages according to the 7^th edition of AJCC staging system were used.(5)

Discrete data were presented as numbers or percentages while continuous variables were presented as mean with range. For statistical comparison, Window SPSS program (Version 13.0, SPSS Inc., Chicago, IL, USA) was used. For univariate analysis, chi-square test and Student's t-test were used according to the type of data while logistic regression analysis was used for multivariate analysis. Survival rate was analyzed using Kaplan-Meier method by comparing with log rank. P-value <0.05 was considered statistically significant.

As a manifestation of the aging process, elderly people have degenerated altered perioperative homeostasis due to slow neovascularization, re-epithelialization, collagen accumulation and vasopermeability.(6,7) Based on the assumption that there is a high risk of developing postoperative complications with increasing age, non-active treatment may be carried out for elderly patients. However, many studies on elderly patients with stomach cancer have reported that elderly patients who underwent radical excision did not have a lower survival rate than that in the middle-aged patients, based on features of clinical pathology and prognosis.(8-11) According to a study in Korea in 1990s, the 5 year postoperative survival rate of elderly gastric cancer patients was 35%,(12) and the overall prognosis has improved by about 20% in 10 years since then.(13) According to the survey of the present study, the older age group had a 5 year survival rate of 63.9%.

According to the analysis, the older age group had a significantly (P<0.001) more number of high-risk patients and higher prevalence rate of accompanying chronic diseases than that in the younger age group (P<0.001). However, no significant difference was found in terms of the postoperative recovery period (P=0.065, Table 2) and postoperative complications (P=0.518, P=0.842, Table 2) between groups. Thus, in spite of the general expectations that the older age group may have more high-risk patients who may need a longer hospital stay, the actual duration of hospital stay was not longer than that in the younger age group, thereby indicating that the progress of postoperative recovery was not slower in the older age group compared to that in the younger age group. Eventually, despite the older age group having more number of chronic diseases and worse preoperative physical status than that in the younger age group, these factors did not affect the development of postoperative complications or progress of recovery. Consequently, active surgical treatments should be considered for elderly gastric cancer patients. According to a recent study on the postoperative results of stomach cancer patient groups between 61~70 years of age and 75 years or older conducted by Mohri et al.,(14) the risk of death caused due to gastric cancer was the same between the groups, and the cancer-specific survival rate was not different between the patient group aged 75 years or older and the all age patient group. Accordingly, in case of the patients who are close to the average life expectancy, standard treatment modalities should be provided for long-term survival.

In the present study, the patients in the older age group were confirmed as having many accompanying diseases, and were at a high risk for surgery. However, if the underlying diseases are confirmed and appropriate care is provided, development of postoperative complications in the older age group may not be different from that in the younger age group. According to the present study, the younger age group had a longer 5 year survival time by about 4 months than that in the older age group (Fig. 1). This is a statistically significant difference. In addition, the multivariate analysis showed that age itself was a risk factor (Table 4, P<0.001).

We confirmed that in gastric cancer, the treatment method and scope of surgery were not different between the older age group and the younger age group, but the postoperative survival time in the older age group could be shorter than that in the younger age group. It can be assumed that the possibility of death caused due to the underlying disease conditions is higher than that caused due to gastric cancer itself in case of the older age group of patients. Accordingly, the older age group of patients should be closely monitored for the underlying disease conditions and development of an additional chronic disease or cancer as well as gastric cancer itself. Nevertheless, without the analysis of the cancer-specific survival rate during the relevant period, the results cannot be interpreted as those of surgical treatment for gastric cancer. This should be considered when a study is conducted, and follow-up monitoring and description of the cause of death in the future should be accurate.

As a limitation of the present study, a selection bias may be present. The patients who were selected for the present study had already undergone all the necessary surgeries. When surgery was decided, patients in a good physical condition could have been recommended to undergo surgery, and elderly patients in a poor physical condition could have not undergone various examinations including endoscopy for detecting gastric cancer. This may lead to a possibility of lack of representativeness of the relevant age groups.

In conclusion, rather than considering old age as a contraindication for surgical treatments, a standard surgical treatment can be recommended for the elderly patients who have a higher chance of suffering from accompanying diseases whether or not they have confirmed accompanying diseases, and if appropriate perioperative care is provided.(15,16)