Lutetium 177 vs Chemotherapy for Advanced Prostate Cancer
Treatment for metastatic prostate cancer is an urgent problem of urology and oncology. The tumor is insidious by the absence of symptoms at an early stage. Symptoms often appear already in the advanced stages. What happens when the diagnosis is not made on time and the tumor remains untreated? In advanced cases, the process of metastasis begins – the tumor progresses, spreads to healthy tissues, and forms secondary cancer.
What is metastatic prostate cancer?
Prostate cancer is a malignant neoplasm with different stages depending on the size, involvement of lymph nodes in the process, and spread. The tumor is called localized prostate cancer if it has not spread beyond the prostate gland.
Metastatic cancer is a disease that has spread beyond the organ where it originally appeared. Cancer cells move through connective tissue and, as a result, enter the circulatory or lymphatic system. After that, they are transferred with blood or lymph until they are fixed in a new place — this is how metastases form.
Signs of prostate cancer spreading
Symptoms of organ damage by metastases may be different, depending on the localization of the malignant process:
- Poor appetite, weakness, fever, weight loss without reason, and other signs of general intoxication.
- Ascites – accumulation of fluid in the abdominal cavity with liver damage.
- Cough, often with blood or mucus, shortness of breath – signs of lung tissue damage.
- Pain syndrome, depending on the organ affected by metastases. If the pain spreads throughout the body, it indicates bone metastasis.
- Dizziness, ataxia (impaired coordination of movements), headaches – signs of the transition of the malignant process to the brain.
- Constipation, diarrhea, and blood in the stool. It can indicate the presence of intestinal metastases.
- Urine with blood, violations of the urination process, and burning – a characteristic signs of a bladder tumor.
Metastases throughout the body are searched for with the help of complex diagnostics – ultrasound, CT, MRI, and tests for cancer markers. Then, treatment is selected depending on which organs are affected since different tissues respond to different therapies.
Options available for advanced prostate cancer
The choice of treatment methods for advanced prostate cancer depends on the type and location of the tumor, its stage, and its size.
Primary therapy options include chemo, radiation, hormonal, and symptomatic therapy (painkillers). Very often, several methods are combined. For example, if the patient has less than three small metastases, they can be treated surgically or with radiation therapy. Radio-guided operations, robotic interventions, or radiosurgical intervention is used in modern surgical treatment. With massive metastases, surgical treatment is not recommended.
Hormone therapy
With a prostate tumor, the level of androgens in the blood increases. The use of hormones contributes to the suppression of their activity. Hormonal treatment is used as an additional method and never serves as the only therapy means. With foci in the bones, hormones help to reduce it and prevent the development of further spreading.
Chemotherapy
In chemotherapy, anti-cancer drugs are used that affect tumor cells. Thus, the growth of the tumor can slow down. The most common types of chemotherapy include docetaxel (Taxotere) and cabazitaxel (Jevtana). These medications are usually prescribed in combination with steroids (hormones).
Radiation therapy
It is used for irradiation before surgery or as the only method if the tumor is not operable. That is relevant if hormone therapy does not have a good effect or there is pronounced discomfort. Radiation therapy can be used to irradiate the primary tumor and metastases. This method can help to remove small metastases. Classical radiation relieves the symptoms of the disease. However, it has many side effects and is poorly tolerated by patients.
Lutetium-177 PSMA treatment
Radionuclide anti-cancer treatment combines therapeutic radioactive isotopes with compounds targeting cells. That is an innovative method approved by the U.S. Food&Drug Administration (FDA). It has shown high effectiveness in treating advanced prostate cancer. The radiopharmaceuticals approved by the FDA include Lutathera (Lutetium dotatate Lu 177) and Pluvicto (Lutetium vipivotide tetraxetan 177).
In healthy prostate cells, a specific protein called prostate-specific membrane antigen (PSMA) is produced in small quantities. Nevertheless, protein expression increases many times in tumor tissue. So, when the malignant tumor spreads to other organs, PSMA also appears in their tissues. Doctors can detect prostate cancer cells with the help of the radioisotope lutetium-177. This diagnostic is performed during PET-CT, and doctors decide whether therapy can be used after reviewing the results.
The radionuclide Lu-177, combined with a somatostatin analog, a protein targeted at cells, creates a drug called Lutathera. It has become a particular type of therapy. It can attach to cancer cells and destroy them.
Comparing results of Lu 177 and Chemotherapy
Recent reports on lutathera's treatment of advanced prostate cancer have shown its effectiveness. The results revealed that the response rate to Lu-177 therapy was higher than after chemotherapy, with lower side effects.
In addition, the scientists reported that patients' relapse-free and overall survival were higher after lutetium therapy. As a result, current research focuses on improving drug safety and reducing side effects.
Why might Chemotherapy Not be the best option?
With chemotherapy, doctors prescribe drugs that can slow or stop cancer growth and prevent its spread to other body parts. Most of them target fast-growing cells that multiply. However, they do not distinguish between healthy and cancer cells.
Entering the bloodstream, they affect the entire body and give more general side effects:
- nausea and vomiting;
- hair loss;
- changes in the blood pattern;
- various effects on the skin and mucous membranes.
Many healthy body cells grow fast, such as bone marrow, digestive tract, and hair follicles. Unfortunately, chemotherapy can also kill these cells, causing hair loss, weakening of the immune system, and other health problems.
Why is Lutetium Treatment so Effective?
Lu-177 PSMA delivers small irradiation to prostate cancer cells everywhere in the body where its metastases have spread. The drug is administered intravenously, and the drug molecule recognizes the target cell and binds to its membrane. Thus, the cancer cell receives a radiation dose and is damaged by the radioactive "cargo."
The advantage of such drugs as Lutater and Pluvicto is the exact direction of radiation. It travels only a short distance beyond the cancer cell and does not harm healthy tissue.
We have a complex article about Lutetoium treatment which explore everything you need to know about modern Lu 177 therapy.
How do doctors check for Lu-177 Effectiveness?
The surface of prostate cells contains a unique protein PSMA (prostate-specific membrane antigen). When a person is healthy, his concentration is insignificant, but with prostate cancer, it increases many times. And in the case of metastases, PSMA is also present on the surface of metastatic cells.
A prerequisite for the success of Lu177-PSMA therapy is the ability of tumor cells to accumulate PSMA. To determine this ability, before treatment, PET-CT with Ga68-PSMA or dosimetry with an iodine isotope is performed to predict the possible effect of treatment. In addition, scintigraphy of the thyroid gland and skeleton is also performed.
The experience of using this method in several leading foreign clinics has shown that in 50% of cases, the condition of patients has improved significantly — to the point that there has been a regression of distant metastases (destruction), which is usually extremely difficult to treat.
Doctors use the following two main criteria to evaluate the effectiveness of Lu177 treatment in patients with metastatic prostate cancer:
- PSA level. Doctors measure the rapid decrease in PSA levels after therapy and track how long the patient remains stable. The response to treatment was determined based on a decrease in the level of PSA in the blood by ≥ 50%. According to the results of studies, about 60% of patients report a decrease in PSA of more than 50%. At the same time, any decrease in PSA occurred in 75% of men. In men, the size of metastases in bones and soft tissues decreased, and pain syndrome became less pronounced.
- PSMA-PET scan. Metastases are visible in the pictures. The treatment results are determined by comparing the images before and after therapy. Then, with the help of regular scans, doctors determine how long the patient remains stable without disease progression.
An additional criterion for evaluating the effectiveness is the overall improvement of symptoms. Studies have shown that therapy can reduce pain and improve quality of life. However, this indicator varies in the study of different groups of patients.
Today, studies of PSMA therapy with lutetium-177 are continuing in large clinics in Italy, Germany, Australia, the Netherlands, and the USA.
PSMA therapy with AiroMedical
Lutetium therapy has become an approved scientifically based method of anti-oncological therapy for advanced prostate cancer. AiroMedical will help you find a suitable clinic with experienced specialists and modern equipment for this therapy.
Our database consists of hundreds of high-quality hospitals worldwide that provide therapy for advanced prostate cancer using Lutathera and Pluvicto.
The best Places to Search for PSMA Therapy might be:
Proper treatment depends on many factors. Cancer patients can consult an oncologist to discuss treatment options and studies supporting these recommendations. The second expert opinion can give more information and help the patient understand whether he is making the right decision considering his needs, health, and treatment goals.
Please, contact us anytime, and we will help you find the optimal solution!
References:
- The Journal of Nuclear Medicine: Long-term follow-up and outcomes of re-treatment
- National Library of Medicine: Update on radioligand therapy with 177 Lu-PSMA
- National Library of Medicine: Lutetium-177-PSMA-617 for Metastatic Castration-Resistant Prostate Cancer
- Oncology Times: Novel Radiation Therapy Induces Responses in Prostate Cancer
