Stem Cell Therapy: A New Hope For Cancer Treatment

Cancer is one of the most difficult health conditions that have challenged medical professionals for years on end and its strong disruptive nature creates difficulties which are showcased by the popular and conventional treatments like chemotherapy and radiation treatement leaving behind a wide range of harsh side effects, sometimes with limited success rate on some cancers. In a quest for more innovative and targeted forms of treatment, stem cell therapy has made an appearance as hope for treatment for this tumultuous challenge of limited cancer therapy. This cutting edge approach grasps on to the unique regenerative capabilities of stem cells to combat cancer cells and repair already damaged tissues. As years go on, stem cell therapy has had time to become more and more refined. Now it has potential to revolutionise cancer treatment offering many opportunities to enhance the quality of life for patients and improve the successs rates towards more positive outcomes.

Chemotherapy drastically drops the healthy white blood cell count by indiscriminately attacking rapidly dividing cells, such as cancer cells. Simmilarly, radiation therapy can destroy cancer cells but also immune cells in the bone marrow especially if large areas are treated- Therefore it is crucial that after treatement the immune system is restored.  Stem cell transplants ensure that the immune system is kept healthy and well playing a vital role in the recovery of many, many patients.

Stem cells are ultimately the building block for all organs, blood tissue and even our immune system! They are unspecialised cells, that that are capable of regenerative renewal and ability to differentiate, which provides us with a multitude of reasons as to why stem cells were considered for use in cancer therapy.  Stem cells hold huge amounts of potential in regenerative medicines, currently being used to treat many forms of blood cancers such as leukemia and lymphoma and other blood disorders like severe apoplectic anaemia. Its also seen potential in treating illnesses like Parkinsons and diabetes and has even been used to treat patients suffering from spinal chord injuries and heart diseases. For over 65 years that stem cell therapy has existed, it has shown growing potential and malleability like nothing else we have seen in years of medical research! 

To be able to be used in therapy, stem cells are harvested from either a donor or the patient and frozen awaiting for transplant. Next they are prepared by intensive processing in a lab before transplant. At the transplant stage occuring 1 to 2 days after the last chemotherapy or radiation dose, they are administered to the patient intravenously, most of the time by injection or infusion, at which point they travel through the bloodstream to the bone marrow where they can grow and produce new and healthy blood cells in the next stage of the therapy. The next step in the process being engraftment which occurs 2 to 4 weeks after transplant varying based on the intensity. It's at this point that patients can become more susceptible to infection. The therapy's success can then be confirmed by a steady rise and maintenance of healthy levels of neutrophils, the most abundant type of white blood cell which acts as the immune system's first line of defense.

 There are two ways in which stem cells can be harvested, allogeniec and autologous.

Allogeniec stem cell transplants, where stem cells are taken from the healthy blood of a donor and used to replace a patients diseased or damaged bone marrow. It is important to ensure that the donor is a close match to the patient to minimise the chance of rejection. Because of this, siblings are common donors however a close match can also be found in registry donors or haploidentical relatives or even collected by umbillical cord blood. The donor match as well as reasons such the prophylaxis used can leave the patient vulnerable to Graft-Versus-Host-Disease, which refers to the donor's immune cells, recognizing the patient's healthy tissue as foreign and attacking. Up to 50% of patients who recieve a stem cell transplant will suffer from acute GVHD and up to 80% from chronic GVDH (National Institute of Health). However, to contradict this, allogeneic stem cell transplants are also likely to cause the Graft-versus-Tumour effect, an immunological process in which the the donor immune cells instead recognise the recipient's cancer cells as foreign and attack. Additionally, due to the immune cells being taken from a healthy donor, the cells are known to be free of cancer therefore posing no threat of the patient gaining a new cancer and decreasing the chance of reoccurrence. The American Society of Heamatology reports that survival rates are increasing across all ethnic groups and according to Livs hospital, top treatment centres now see one year survival rates over 80% showcasing its potential in achieving reliable cancer treatment demonstrated by it's current advances in the medical field.

Autologous stem cell transplants, where the patients own stem cells are used. They are harvested and frozen before the patient receives chemotherapy or radiation therapy after which they can be reintroduced to the patient's system. It shows an advantage in avoiding the Graft-versus-Host Disease with the stem cells recieved being the patient's own leaving no risk of the immune system attacking the body itself which is otherwise a major complication. However, the harvesting of stem cells from the patient themselves, further suppresses the immune system making them susceptible to potential infections for weeks or perhaps months afterwards as well as a very small risk of developing a new cancer due to chemotherapy or radiation. 405 patients with malignant lymphoma and 472 patients with multiple myeloma were analysed with a median follow-up from the initial malignant diagnosis.  89 of these patients (approximately 0.1%) suffered from invasive secondary malignancies (30 haematologic malignancies, 64 solid tumours across the group), as well as a non-melanoma skin cancer observed in 29 patients. 48% of patients with solid tumours had them diagnosed in an early stage of the disease and had a chance of recovery. 5% of the patients developed an invasive malignancy within 5 years, 12% within 10 years and 21% within 20 years. Those most at risk were much older patients, and in the diagnosis of lymphoma, males were more at Risk. ( Data from the National Institute of Health).Another way in which autologous stem cells aid cancer treatment indirectly is by allowing the patient to take higher doses of chemotherapy therefore eradicating more cancer cells faster than the usual dose. Furthermore, even if it fails to destroy the cancer, for example in cases of refractory cancer or recurrent cancer,  an autonomous stem cell transplant can put cancer into long term remission often used as a treatement when other treatements fail. In almost every scenario it's used in, an autologous stem cell transplant provides relief to the patient, either permanently or temporarily. 

Throughout this process, stem cell therapy has shown promise and held it's place in treatment of cancer, particularly blood cancers as it helps rebuild the damaged immune system after a patient's intense chemotherapy and radiation therapy, which if not repaired can cause a variety of issues such as reduced tumor control, meaning the cancer spreads faster and more efficiently. This only emphasizes the strengths of stem cell therapy as a response to cancer, keeping the immune system healthy and well. 

In conclusion, It is safe to say that stem cell therapy has revolutionised the idea of treatment with it being used to treat a wide variety of debilitating illnesses and diseases, including cancer, showcasing the usage of  it's distinctive capacity for regeneration and specialised cell differentiation. Utilising its capabilities to combat in the enfeeble terrain of cancer shows its potential to overcome the constraints of traditional therapies and improve the outcome and quality of life for those who are suffering with this debilitating disease, forever. Although many challenges remain, the research and clinical trials that are taking place currently, are paving the way for a future in which we see more refined and effective treatment. By unraveling its complexities, as its potential grows day by day, stem cell therapy has shows great promise in transforming cancer care and pushing the field of medical science to new heights.