(I) Chemotherapy for pound cancer
After radical cystectomy for muscle-invasive bladder cancer, up to 50% of patients will develop metastases, and the 5-year survival rate is 36% to 54%. For patients with T3 to -T4 and/or N+M0 bladder cancer at high risk, the 5-year survival rate is only 25% to 35%. Bladder cancer is sensitive to cisplatin-containing chemotherapy regimens, with an overall effective rate of 40% to 75%, of which 12% to 20% of patients achieve complete remission of local lesions, and about 10% to 20% of patients can achieve long-term survival.
1, neoadjuvant chemotherapy For patients with operable T2 to T4a stage, neoadjuvant chemotherapy is feasible before surgery. The main purpose of neoadjuvant chemotherapy is to control the local lesions, make the tumor down-stage, reduce the difficulty of surgery and eliminate micro-metastases, and improve the long-term survival rate after surgery. After neoadjuvant chemotherapy, the mortality rate of patients can be decreased by 12%-14%, the 5-year survival rate can be increased by 5%-7%, and the distant metastasis rate can be decreased by 5%, and for T3-T4a patients, the improvement of survival rate may be more obvious. Neoadjuvant chemotherapy has also been used as a means of bladder preservation, but this approach is highly controversial. The course of neoadjuvant chemotherapy is not clearly defined, but at least 2 to 3 cycles of cisplatin-based combination chemotherapy should be used.
2. adjuvant chemotherapy For patients with clinical stage T2 or T3, postoperative adjuvant chemotherapy can be used after radical cystectomy if the pathology shows positive lymph nodes or is pT3 and if neoadjuvant chemotherapy was not administered preoperatively. Adjuvant chemotherapy may also be used after surgery in patients with partial cystectomy if the postoperative pathology shows positive lymph nodes or positive cut margins or pT3. Adjuvant chemotherapy can delay disease progression and prevent recurrence, but the results of various studies on adjuvant chemotherapy are controversial due to small sample size, statistical and methodological confusion.
For clinical T4a and T4b patients, if CT shows negative lymph nodes or abnormal lymph nodes are found to be negative by biopsy, chemotherapy or chemotherapy + radiotherapy, or surgery ± chemotherapy (only for patients with selective cT4a) is feasible. if CT shows positive enlarged lymph nodes by biopsy, chemotherapy or chemotherapy + radiotherapy is performed.
4. Systemic systemic chemotherapy should be routinely performed for metastatic bladder cancer, especially for unresectable, diffuse metastases and measurable metastatic lesions. Systemic systemic chemotherapy ± radiotherapy is also feasible for those who are physically unfit or unwilling to undergo radical cystectomy.
5.Intra-arterial chemotherapy is used to treat local tumor lesions by infusing chemotherapeutic drugs into the internal iliac arteries bilaterally, which is more effective than systemic chemotherapy for local tumors and is often used as neoadjuvant chemotherapy. The literature reports that the complete remission rate of arterial catheter chemotherapy + full-dose radiotherapy can reach 78%-91%, and arterial catheter chemotherapy is not effective as adjuvant chemotherapy. Chemotherapeutic drugs can be selected from MTX/CDDP or CDDP alone or 5-Fu+ADM+CDDP+MMC, etc.
6.Chemotherapy regimen
(1) GC (gemcitabine and cisplatin) regimen: This combination chemotherapy regimen is considered the current standard first-line treatment regimen and can be chosen by more patients. Gemcitabine 800-1,000 mg/m2, IV on days 1, 8 and 15; cisplatin 70 mg/m2, IV on day 2; repeated every 3 to 4 weeks for 2 to 6 cycles. The study showed that the GC regimen had a CR (complete remission rate) of 15%, PR (partial remission rate) of 33%, median disease progression time of 23 weeks, and overall survival time of 54 weeks, which was better tolerated than the MVAC regimen.
(2) MVAC (methotrexate, vincristine, adriamycin, cisplatin) regimen: It is traditionally the standard first-line treatment regimen for urothelial carcinoma of the bladder. Methotrexate 30 mg/m2 IV on days 1, 15 and 22, vincristine 3 mg/m2 IV on days 2, 15 and 22, adriamycin 30 mg/m2 IV on day 2 and cisplatin 70 mg/m2 IV on day 2, repeated every 4 weeks for 2 to 6 cycles. Two randomized prospective studies have confirmed that the MVAC regimen is significantly more effective than single-drug chemotherapy. Several studies have shown that this regimen has a CR of 15%-25%, an effective rate of 50%-70%, and a median survival time of 12-13 months.
(3) Other chemotherapy regimens: TC (paclitaxel and cisplatin) regimen, TCa (paclitaxel and carboplatin) regimen, DC (doxorubicin and cisplatin) 3-week regimen, GT (gemcitabine and paclitaxel) regimen, and CMV (methotrexate combined with vincristine and cisplatin) regimen and CAP (cyclophosphamide combined with adriamycin and cisplatin) regimen. gct (gemcitabine combined with cisplatin and paclitaxel) regimen The GCT (gemcitabine combined with carboplatin and paclitaxel) regimen, the GCaT (gemcitabine combined with carboplatin and paclitaxel) regimen and the ICP (isocyclophosphamide combined with cisplatin and paclitaxel) regimen are three chemotherapy regimens with high toxic side effects and are rarely used clinically.
(II) Radiotherapy for bladder cancer
In some cases, patients with muscle-infiltrating bladder cancer are unwilling to undergo radical cystectomy in order to preserve the bladder, or the patient’s systemic condition cannot tolerate radical cystectomy, or when radical surgery can no longer completely remove the tumor and the tumor can no longer be removed, bladder radiation therapy or chemotherapy + radiation therapy can be chosen. However, for muscle-infiltrating bladder cancer, the overall survival of patients treated with radiotherapy alone is shorter than that of radical cystectomy.
1.Radical radiotherapy External bladder irradiation methods include conventional external irradiation, three-dimensional conformal radiotherapy and intensity-modulated conformal radiotherapy. The target area dose of radiation therapy alone is usually 60-66Gy, the daily dose is usually 1.8-2Gy, and the whole course of treatment does not exceed 6-7 weeks. Currently, the commonly used radiotherapy schedule is: 50~55Gy, completed in 25~28 sessions (>4 weeks); 64~66Gy, completed in 32~33 sessions (>6.5 weeks). The local control rate of radiotherapy is about 30% to 50% [36], and the overall 5-year survival rate of patients with muscle-invasive bladder cancer is about 40% to 60%, with a tumor-specific survival rate of 35% to 40% and a local recurrence rate of about 30%.
Clinical studies have shown response rates of 60% to 80% with cisplatin-based combination radiotherapy, 5-year survival rates of 50% to 60% [38-40], and possible bladder preservation in 50% of patients, but long-term randomized study results are lacking. A large phase II clinical study suggests that combined radiotherapy improves the likelihood of bladder preservation compared with radiotherapy alone. Patients with bladder preservation should be closely followed and aggressive remedial radical cystectomy should be performed in case of recurrence.
European literature reports that patients with small T1/T2 tumors can be treated by cystotomy (with or without partial cystectomy) to expose the tumor and then place radioactive iodine, iridium, tantalum, or cesium for intra-tissue brachytherapy, followed by combined external irradiation and bladder-preserving surgery. Depending on the stage of the tumor, the 5-year survival rate can be 60% to 80%.
2.Adjuvant radiotherapy There is no obvious superiority of radiotherapy before radical cystectomy. If the residual tumor is not cut by total cystectomy or partial cystectomy or the postoperative pathological margin is positive, postoperative adjuvant radiotherapy is feasible.
3.Palliative radiotherapy Through short course of radiotherapy (7Gy×3 days; 3~3.5Gy×10 days) can alleviate the uncontrollable symptoms caused by huge bladder tumor, such as hematuria, urinary urgency, pain and so on. However, this treatment can increase the risk of acute intestinal complications, including diarrhea and painful abdominal cramps.
Recommendations.
1.Chemotherapy and radiotherapy are mainly used as adjuvant treatment for bladder cancer.
2.Systemic chemotherapy is the standard treatment for metastatic bladder cancer.
3. Chemotherapy should choose platinum-containing combination chemotherapy regimen, and MVAC regimen and GC regimen are the first-line chemotherapy regimen.
4.Chemotherapy or radiotherapy can be used as a selective alternative to radical surgery, but the efficacy is inferior to that of radical surgery.
5, Combined radiotherapy has the potential to improve the possibility of bladder preservation, but should be closely followed.