Why Cancer May Still Recur or Spread After Treatment?
Cancer remains one of the leading global health threats. Many patients undergo surgery, chemotherapy, or radiotherapy believing the cancer cells have been completely eliminated, only to discover recurrence or metastasis months or even years later. This phenomenon often causes confusion and anxiety. Medically, this is known as cancer recurrence or metastasis. It does not necessarily mean the initial treatment failed, but rather reflects the complex nature of cancer and the influence of the body’s overall metabolic environment.
Main Reasons for Recurrence or Metastasis After Treatment
Even when chemotherapy and radiotherapy successfully kill a large number of active cancer cells, the risk of recurrence persists. Common contributing factors include:
- Residual or dormant cancer cells: Treatment may not eliminate every cancer cell. Some remain in a dormant state, less sensitive to chemotherapy or radiotherapy, and can reactivate months or years later.
- Micrometastasis: Visible tumours may be removed by surgery, but some cancer cells may have already spread via the bloodstream or lymphatic system, forming microscopic metastases that imaging may not detect early.
- Cancer cell adaptation and resistance: Cancer cells are highly mutable. Some may develop resistance to treatment. The therapy process can sometimes alter the body’s internal environment (such as immune response or inflammation), indirectly promoting the proliferation of remaining cancer cells.
- Influence of the body’s overall metabolic environment: Cancer development is closely linked to the patient’s metabolism, immune function, and internal environment. If the body’s conditions favour cancer cell survival, the chance of recurrence increases. Conversely, optimising the body’s metabolic state can help reduce this risk.
Chemotherapy and radiotherapy can affect normal cells and the immune system — a known side effect — but they remain important tools for controlling cancer. Integrative medicine approaches can serve as supportive measures to improve treatment tolerance, protect normal cells, and enhance patients’ quality of life.
Common Myths About Cancer Treatment Clarified
- Do cancer cells only grow on sugar? Can diet “starve” cancer cells?
Cancer cells do prefer glucose for energy (known as the Warburg effect), but they can also adapt to other energy sources. Completely eliminating carbohydrates is not advisable, as it may lead to malnutrition, reduced physical strength, and negatively affect treatment outcomes and recovery.
However, controlling refined sugars and high-glycaemic-index foods is a reasonable approach. In cancer supportive care, low-carbohydrate diets or controlled fasting (such as intermittent fasting or fasting-mimicking diets) may be considered on an individual basis as metabolic regulation strategies to support conventional treatment. These approaches must be carried out under the supervision of a professional medical team. The goal is to optimise the body’s metabolic environment and enhance treatment efficacy, rather than solely attempting to “starve” cancer cells. Any dietary changes must be combined with standard treatment and guided by a doctor.
- Is cancer purely caused by gene mutation?
Gene mutations are an important cause of cancer, but the process is extremely complex and influenced by many factors, including lifestyle, environment, and the body’s metabolic state. A single gene change cannot explain all cancers. Metabolic alterations, such as mitochondrial dysfunction, also play a key role. Integrative medicine addresses metabolism, immunity, and overall health together.
- Are there many carcinogens in daily life?
Mobile phone radiation, barbecued foods, and similar items are often mentioned, but assessment must consider dosage, exposure duration, and scientific evidence. Proven carcinogens (such as smoking) should be avoided, but many everyday claims need to be viewed rationally without causing excessive panic.
- Why is chemotherapy or radiotherapy still needed after surgical removal?
Surgery mainly removes visible tumours but cannot guarantee the elimination of all microscopic cancer cells or those that have already spread. Adjuvant chemotherapy and radiotherapy aim to clear these hidden threats and prevent recurrence. The need depends on cancer stage, type, and the patient’s overall condition. Supportive care can help patients better tolerate these treatments.
BMS Clinic’s Cancer Support Philosophy: Optimising the Body’s Metabolic Environment
BMS Clinic, a leading integrative medicine clinic in Hong Kong, specialises in cancer supportive care and integrative oncology. We believe cancer management should not rely on a single treatment modality. Instead, it requires combining advanced medical care with personalised supportive therapies to help patients strengthen immunity, improve quality of life, and receive comprehensive support during treatment.
Key areas of focus include metabolic regulation, nutritional support, immune function optimisation, and the development of personalised plans. Whether during or after treatment, improving the body’s overall metabolic state is crucial. BMS Clinic encourages patients, under the guidance of a professional team, to actively adjust their lifestyle. This can enhance treatment effectiveness, reduce recurrence risk, and improve quality of life.
Modern medicine combined with integrative support has helped many cancer patients maintain good long-term outcomes. Recurrence is not inevitable — the key lies in comprehensive care of both body and mind.
Important Note
The information above is for reference only and is based on general medical knowledge and integrative medicine principles. Individual health conditions, dietary adjustments, or treatment plans vary from person to person. Please always consult a qualified doctor. BMS Clinic offers personalised cancer supportive assessments. Feel free to make an appointment to learn about a comprehensive support plan suitable for you.
Health begins with accurate knowledge and professional support. BMS Clinic is committed to accompanying patients and their families on the journey to better health.
Disclaimer：
The information provided in this article is for educational and informational purposes only. It is not intended to diagnose, treat, cure, or prevent any disease, nor should it replace professional medical advice. Readers are encouraged to consult with a qualified healthcare provider or integrative oncology specialist before making any changes to their diet, treatment plan, or lifestyle based on the content herein. Therapies and tests mentioned, including immune or integrative treatments, should always be…
All product names, test references, and therapy mentions are for informational context only and do not constitute endorsement. Results and experiences may vary among individuals.
References
- Studies on the Warburg effect and metabolic approaches in cancer treatment (e.g., ketogenic diet and fasting as adjuncts).
- Research on dietary interventions, caloric restriction, intermittent fasting, and their potential role in supporting conventional cancer therapies while reducing side effects.