Bladder cancer - symptoms and treatment

The main method of treatment for most patients with malignant neoplasms of the bladder will remain surgery. The surgical method is recognized as the main one in the treatment of patients with bladder cancer in the world.

From a clinical point of view, the division of bladder cancer into non-invasive, or non-muscle-invasive, and muscle-invasive, plays a significant role in the choice of treatment. The development of non-muscle-invasive bladder cancer (Tis, Ta, T1) is difficult to predict. Two main factors determine the fate of a patient with this type of cancer: recurrence and progression of the disease. Muscle-invasive bladder cancer has an unpredictable course and is at risk of rapid recurrence. In 40-80% of cases after transurethral resection (TUR), a relapse develops within 6-12 months, and invasive cancer develops in 10-25% of patients. With each new relapse, the likelihood of saving the bladder decreases.

Non-Muscle Invasive Bladder Cancer Treatment

The main strategy for the treatment of non-muscle invasive bladder cancer is based on the radical removal of the tumor, preventing recurrence, metastasis and degeneration into invasive forms of cancer.

There are various types of organ-preserving surgical treatment of bladder cancer:

• transvesical resection of the bladder (resection of the tumor through an incision in the wall of the bladder);
• TUR - transurethral resection;
• TUR-vaporization - a type of electrosurgical treatment that combines advantages of tissue resection and vaporization.

With the advent of modern endoscopic techniques for the surgical treatment of non-muscle-invasive bladder tumors, the method of transvesical resection has become a rare intervention.

According to the current recommendations of the European Association of Urology (2017), the recognized standard of surgical organ-preserving treatment of patients with non-muscle-invasive bladder cancer is considered to be primary therapeutic and diagnostic transurethral resection of the bladder (TURB) 4. The objectives of the intervention are: verification of the diagnosis and staging of the tumor ( determination of the T category and the degree of tumor differentiation), determination of possible risks of recurrence and progression based on the obtained morphological data (number of tumor foci, their diameter, presence of concomitant carcinoma in situ) and removal of visible neoplasms.

After TUR MP, all patients undergo a single early (within 6 hours) instillation (drip injection) of a chemotherapy drug into the bladder (the drug is chosen by the doctor). This has been shown to reduce relapse rates. The main goal of intravesical drug therapy for bladder tumors is to maximize the effect of the drug on the remnants of the tumor (cancer cells).

Further treatment after TUR MP and a single instillation of a chemotherapy drug depends on the results of the histological examination and the risk group to which the patient belongs.

Treatment after TUR MP and early single chemotherapy instillation:

• In the low-risk group: further treatment may not be carried out, since the likelihood of relapse and progression is negligible.
• In the high-risk group: adjuvant (auxiliary) intravesical immunotherapy with tuberculosis vaccine - BCG (full dose) with maintenance therapy for 1-3 years. At the highest risk of tumor progression or failure of BCG therapy, cystectomy (removal of the bladder or part of it) is indicated.
• In the intermediate risk group: adjuvant intravesical chemotherapy (drug chosen by the doctor) for no more than 1 year or adjuvant intravesical immunotherapy BCG vaccine (full dose) with maintenance therapy for 1 year.

Intravesical post-resection drug chemo- or immunotherapy is the second method of treatment for non-muscle-invasive bladder cancer after TUR. Intravesical drug therapy is divided into prophylactic, carried out to prevent the occurrence of relapses after removal of all visible tumors, and therapeutic, carried out to destroy residual, partially resected and failed tumors

Based on the type of agent used, intravesical therapy is divided into chemotherapy (CT) and immunotherapy (IT). They differ in the mechanism of action of the drugs used, indications, duration of treatment and effectiveness. 35 different drugs, including cytostatics, immunomodulators and vitamins, have been used for adjuvant purposes in Ta, T1 stages of bladder cancer, and only a few of them have been effective.

Treatment of muscle-invasive bladder cancer

Muscle-invasive bladder cancer is a potentially fatal disease, as without treatment, patients die within 24 months.It should be noted that cystectomy is an organ-removing method of surgical treatment, in which the patient's quality of life deteriorates markedly. An integral part of cystectomy is the removal of lymph nodes.

Radical cystectomy is also indicated when organ-sparing treatment of non-muscle-invasive bladder cancer, poor prognosis and its recurrence is not possible 48. According to the National Cancer Control Network (NCCN) 2017 and the European Association of Urology (EAU) The volume of intervention in non-muscle-invasive bladder cancer is indicated only in the following situations: in the absence of a response to immunotherapy with BCG vaccine after TUR, in case of tumor recurrence (with a cytologically confirmed diagnosis) 48.

At present, laparoscopic techniques are widely used and it has become possible to perform cystectomy using a robot-assisted technique. To preserve sexual function in men, a nerve-sparing cystectomy is performed with preservation of the cavernous neurovascular bundles 8.

An integral part of radical cystectomy is the restoration of the reservoir function of the bladder.

Radical cystectomy provides a 5-year survival rate in only 50% of patients. In this regard, since the 1980s, preoperative chemotherapy has been used to improve such unsatisfactory results. The use of neoadjuvant cisplatin-containing combined chemotherapy improves overall 5-year survival by 5-8% 8.

Salvage cystectomy is indicated in patients who fail conservative therapy, relapse after bladder-sparing treatment, in the presence of non-transitional cell tumors, and only for palliative purposes 8.

Performing only TUR for muscle-invasive bladder cancer does not apply to radical treatment 8.

External radiation therapy can serve as an alternative treatment for patients with contraindications to radical surgery 8.