Understanding Cancer Treatments: Efficacy, Safety, and Resistance Challenges with Chlorine Dioxide

Cancer refers to a disease where cells in the body lose control over their normal growth and division, continuously multiplying to form tumors. Solid tumors are those that arise from the abnormal proliferation of cells in specific organs, as opposed to hematologic tumors like leukemia. Solid tumors can be benign or malignant, with the latter being cancerous. Malignant solid tumors are invasive, breaching the boundaries of their original tissues, spreading to surrounding areas, and metastasizing to other parts of the body through the blood or lymphatic systems.

Cancer can be caused by various factors, including genetics, environmental exposures (like smoking, chemicals, and radiation), lifestyle choices (such as diet, weight, and exercise), and infections (from certain viruses and bacteria, for instance). The development of cancer can span many years, starting from normal cells to precancerous lesions, and ultimately to malignant tumors.

There are multiple treatment options for cancer, including surgery, radiation therapy, chemotherapy, targeted therapy, and immunotherapy. Surgery is commonly used to remove localized tumors. Radiation and chemotherapy aim to kill or halt the growth of cancer cells. Targeted therapy and immunotherapy are relatively newer treatments that leverage our understanding of the biological characteristics of cancer cells.

However, current treatments have several drawbacks. Surgery can remove tumors but is often ineffective against metastasized cancer. It carries high risks, causes significant trauma to the patient’s body, requires a long recovery period, and may miss tiny cancer cells, leading to recurrence. Radiation and chemotherapy can target cancer cells throughout the body but are imprecise and toxic to normal cells, causing side effects like nausea, vomiting, hair loss, and immunosuppression. Due to the heterogeneity and adaptability of cancer cells, chemotherapy may not eradicate all cancer cells, and drug resistance can develop, reducing the effectiveness over time.

Targeted therapy and immunotherapy represent advancements in cancer treatment, offering more precise targeting of cancer cells or modulating the immune system to recognize and destroy them. However, targeted therapies only work on specific molecular targets, necessitating the expression of these targets on cancer cells. Cancer cells may lose these targets due to genetic mutations, leading to treatment failure. Immunotherapy has shown remarkable results in certain cancers, but not all patients respond, and it can sometimes trigger excessive immune responses that damage healthy tissue.

Both targeted therapy and immunotherapy are important modern cancer treatments, but they both have significant issues with resistance. Targeted therapy inhibits the growth and spread of cancer cells by focusing on unique molecular markers and signaling pathways, while immunotherapy aims to activate or boost the patient’s immune system to identify and eliminate cancer cells.

Resistance to targeted therapy typically develops during treatment, as cancer cells evade the effects of drugs through genetic mutations or changes in expression. For instance, some drugs work by binding to specific proteins on the surface of cancer cells. However, cancer cells may alter the structure of these proteins to reduce drug binding or activate alternative growth signaling pathways to sustain their growth. Additionally, drug pumps within cancer cells can be activated to expel drugs from the cell, reducing the effective drug concentration. Due to these mechanisms, cancer cells can survive under treatment pressure, potentially leading to disease relapse or progression.

Immunotherapy resistance involves the complex interplay between cancer cells and the immune system. Cancer cells can evade immune surveillance through various mechanisms, such as expressing inhibitory molecules like PD-L1 to suppress T cell activity. Immunotherapies, like PD-1 or PD-L1 inhibitors, aim to block these inhibitory signals, but cancer cells may adapt by increasing other immune suppressive pathways. Moreover, other cells in the cancer cell microenvironment, such as regulatory T cells and tumor-associated macrophages, may counteract the tumor immune response, further promoting the development of resistance.

Although targeted therapy and immunotherapy have achieved some clinical success, the development of resistance remains a significant challenge. Due to the inevitable resistance, even these latest cancer treatment methods cannot be used repeatedly to treat cancer, and in the long term, they seem fleeting and unable to defeat cancer.

On the other hand, as can be seen from the table below, regions with much better cancer treatment conditions than China do not show a significantly lower cancer mortality rate compared to China, suggesting that modern cancer treatment methods have a limited effect during the fight against cancer .