Colorectal cancer (CRC) is a disease that predisposes the elderly, with approximately 70% of patients over the age of 65 and 40% over the age of 75, according to SEER data. In recent years, overall survival of CRC patients has improved significantly due to improvements in treatment, but survival of elderly patients has not improved significantly. A recent review of chemotherapy for CRC in the elderly was published in the WJG journal by Kim, MD, in Korea. Overview of the current state of treatment Poor survival outcomes in elderly patients are associated with many factors, such as poorer economic conditions, limited health resources, and more comorbidities. Inadequate treatment may be the most significant factor contributing to low survival rates in older adults with CRC. Reasons for inadequate treatment include inadequate interventional diagnostic evaluation, incomplete surgery, and inadequate intensity of chemotherapy. 1. Inadequate staging of elderly CRC patients is associated with decreased rates of surgery and adjuvant or palliative chemotherapy/radiotherapy. The Dutch study showed that the long-term prognosis of elderly CRC patients with 1-year survival was similar to that of middle-aged patients, suggesting that elderly patients in good physical condition can benefit from more intensive treatments such as surgery, adjuvant chemotherapy/radiotherapy, and palliative chemotherapy. In contrast, the focus of treatment for elderly patients in poorer physical condition should be on palliative care, and physiological age should not be a contraindication to adjuvant or palliative chemotherapy. 2. Lack of treatment guidelines for elderly patients may be an important reason for inadequate treatment. Older patients are not usually included in clinical trials and therefore lack evidence-based preferential treatment options. Clinicians determining treatment options for elderly patients are usually based on general population data, but this extrapolation of conclusions is dangerous for elderly patients with high comorbidity and reduced cognitive function. Evaluation of the elderly patient Assessing whether the benefits of treatment outweigh the risks of complications or death is a major issue to be weighed in the treatment of elderly patients with CRC. Older patients imply an increase in age-related health problems (e.g., comorbidities, disability, physical and cognitive decline, etc.) and an increased incidence of cancer, and the proper selection of patients for effective and safe treatment becomes critical. Aging states should undergo a geriatric assessment (CGA), which provides an in-depth assessment of older patients’ comorbidities, death, and their lives in order to make the right treatment choices.CGA is an important tool for predicting the age of physical function in older patients, assessing patients’ comorbidities, nutritional status, cognitive function, socioeconomic status, medication history, and geriatric syndromes. CGA can help physicians develop a rational treatment plan for elderly patients, but it is time-consuming. A simple CGA is now also used to perform cancer-specific geriatric assessment (CSGA), which involves 7 main aspects, including functional status, comorbidities, medication history, cognitive function, physiological status, social function and support, and nutritional status. Postoperative adjuvant chemotherapy for colon cancer Adjuvant chemotherapy is mainly used for stage III and high-risk stage II colon cancer, where clinical concerns about drug toxicity make it less common for elderly patients to receive postoperative adjuvant chemotherapy. A retrospective study showed that only 55% of elderly patients received adjuvant chemotherapy within 3 months after radical surgery, and the proportion of patients receiving treatment declined rapidly with age. Between 1990 and 2004, postoperative 5-FU/LV was the standard of care for stage III colon cancer, with a 26% reduction in mortality. 5-FU/LV chemotherapy was equivalent in PFS, DFS, and OS in older and younger patients with no significant increase in toxicities. The 2004 MOSAIC trial demonstrated that 5-FU/LV in combination with oxaliplatin improved DFS and OS in patients with stage III colon cancer, but the benefit of adjuvant 5-FU/LV in combination with oxaliplatin in older patients remains controversial. Retrospective studies have shown little survival benefit from adding oxaliplatin to the treatment of elderly patients with stage III colon cancer over 75 years of age; other studies have shown no significant improvement in DFS and OS with the addition of oxaliplatin; and subgroup analyses of the results of several trials have not shown a benefit of oxaliplatin in elderly patients, or even a trend toward lower survival. In conclusion, the efficacy of 5-FU/LV or capecitabine for postoperative adjuvant therapy in older patients is similar to that in younger patients. No prospective trials have confirmed the benefit of oxaliplatin-containing regimens in older patients, but individualized consideration is needed to determine whether to administer oxaliplatin-containing chemotherapy in patients older than 70 years. Adjuvant radiotherapy for rectal cancer The standard treatment modality for young patients with locally progressive rectal cancer is a combination of total rectal mesenteric resection, radiotherapy, and chemotherapy. The clinical interest in the benefits of combined therapy is less than the associated complications, and thus this combined treatment modality is less commonly used in older patients. Studies have shown that perioperative radiotherapy for rectal cancer reduces the risk of local recurrence and death, but the rate of non-cancer-related deaths (e.g., cardiovascular disease, radiation enteritis, hypertension, etc.) associated with radiotherapy is high. There are no results from randomized studies of perioperative radiotherapy for rectal cancer in the elderly. Retrospective studies have shown that preoperative radiotherapy increases the chance of anus-preserving surgery in patients over 70 years of age, but results regarding tolerability are controversial. Some studies suggest that older patients have similar tolerability and response to treatment as younger patients, but others suggest that most older patients need to end treatment early, or have treatment interruptions or lower doses. This suggests that older patients with rectal cancer should be more cautious when administering combination therapy. Physiologic age is not a limiting factor for older patients to receive curative treatment for rectal cancer, and multidisciplinary collaboration for individualized treatment is recommended for older patients. Combination therapy modalities that are effective for younger patients should be considered for older patients whose medical status allows it. Palliative chemotherapy for metastatic CRC Treatment of metastatic CRC has evolved rapidly over the past decade due to the advent of biologically targeted drugs and the development of surgical techniques. Modern chemotherapy for metastatic CRC includes a variety of active agents such as 5-FU/LV, capecitabine, irinotecan, oxaliplatin, cetuximab, bevacizumab, panitumumab, abciximab, and regifenib. Cytotoxic chemotherapy Cytotoxic chemotherapy is the mainstay of treatment for metastatic CRC, and several studies have demonstrated that combination chemotherapy is effective and well-tolerated in older patients. 5-FU/LV and capecitabine are the 2 most widely used agents and are tolerated and tolerated by older patients as well as younger patients. Irinotecan can be used in metastatic CRC, and studies have shown no effect of aging on OS and PFS with irinotecan therapy, but an increased risk of grade 3/4 diarrhea and neutropenia, and caution should be exercised with this drug. It has also been demonstrated that irinotecan combined with 5-FU/LV or capecitabine has better ORR and PFS than 5-FU/LV or capecitabine treatment in both older and younger patients and does not appear to have a significant increase in toxicity. Oxaliplatin regimens such as FOLFOX, XELOX, or irinotecan + oxaliplatin are effective in metastatic CRC. However, the addition of oxaliplatin to the treatment of elderly patients does not appear to improve PFS and a stop-and-go strategy can be adopted to minimize toxicity. In conclusion, most trials have shown that the efficacy and toxicity of palliative cytotoxic therapy in older patients with metastatic CRC are similar to those in younger patients. Combination chemotherapy should be considered for older patients with good PS scores, while older patients with poor physical status can be treated with single agent or stop-and-go strategies to reduce toxicity. Targeted therapies Targeted therapies significantly improve outcomes in a variety of malignancies, and studies have evaluated the efficacy of bevacizumab, cetuximab, and panitumumab in the treatment of metastatic CRC in the elderly. The addition of bevacizumab to conventional chemotherapy significantly improved PFS and OS in patients over 65 years of age, but also increased arterial thrombotic events (ATEs), with no significant increase in other toxicities. Bevacizumab in combination with capecitabine is an effective and well-tolerated regimen. Cetuximab and panitumumab are less commonly used in the first-line treatment of metastatic CRC in older patients in pilot studies, and can be used alone or in combination with irinotecan to treat older patients with no less effectiveness than younger patients. Available studies suggest that KRAS-free mutations imply a higher response rate and PFS, and therefore the KRAS status needs to be clarified prior to treatment. Targeted therapy for older patients with metastatic CRC looks very promising because it is effective and less toxic than traditional cytotoxic chemotherapy. However, because targeted therapies can lead to specific toxicities, their use should be closely monitored and toxicity detected early. Conclusion Although CRC is the leading cause of cancer-related deaths in older adults, older patients are often not included in clinical trials and are inadequately staged and treated. Old age per se is not a limiting factor for adjuvant or palliative care, and careful CGA evaluation is required to determine treatment options. All patients are managed in a collaborative multidisciplinary setting, and treatment is individualized. 5-FU/LV and capecitabine benefit as adjuvant therapy for older stage III colon cancer as well as younger patients without increased toxicity; combination therapy remains controversial, but combination treatment modalities can be used with caution in older patients with locally progressive rectal cancer; combination chemotherapy can be considered in older patients with metastatic CRC, and single agent or stop-and-go strategies can be used in frail older patients; targeted therapy is effective and less toxic and can also be used in Targeted therapy is effective and less toxic and can also be used for elderly patients with metastatic CRC.