Comparison of 30 mg and 40 mg of mitomycin C intravesical instillation in Korean superficial bladder cancer patients: prospective, randomized study

The Role of Mitomycin C in Intermediate-risk Non-muscle-invasive Bladder Cancer: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

Intravesical mitomycin C (MMC) instillations are recommended to prevent recurrence of intermediate-risk non-muscle-invasive bladder cancer (IR-NMIBC); however, the optimal regimen and dose are uncertain. Our aim was to assess the effectiveness of adjuvant MMC and compare different MMC regimens in preventing recurrence.

METHODS

We performed a comprehensive search in PubMed, Scopus, and Web of Science in November 2023 for studies investigating recurrence-free survival (RFS) among patients with IR-NMIBC who received adjuvant MMC. Prospective trials with different MMC regimens or other intravesical drugs as comparators were considered eligible.

KEY FINDINGS AND LIMITATIONS

Overall, 14 studies were eligible for systematic review and 11 for meta-analysis of RFS. Estimates of 1-yr, 2-yr, and 5-yr RFS rates were 84% (95% confidence interval [CI] 79-89%), 75% (95% CI 68-82%), and 51% (95% CI 40-63%) for patients treated with MMC induction plus maintenance, and 88% (95% CI 83-94%), 78% (95% CI 67-89%), and 66% (95% CI 57-75%) for patients treated with bacillus Calmette-Guérin (BCG) maintenance, respectively. Estimates of 2-yr RFS rates for MMC maintenance regimens were 76% (95% CI 69-84%) for 40 mg MMC (2 studies) and 66% (95% CI 60-72%) for 30 mg MMC (4 studies). Among the studies included, BCG maintenance provided comparable 2-yr RFS to 40 mg MMC with maintenance (78% vs 76%). RFS did not differ by MMC maintenance duration (>1 yr vs 1 yr vs <1 yr).

CONCLUSIONS AND CLINICAL IMPLICATIONS

MMC induction and maintenance regimens seem to provide short-term RFS rates equivalent to those for BCG maintenance in IR-NMIBC. For adjuvant induction and maintenance, 40 mg of MMC appears to be more effective in preventing recurrence than 30 mg. We did not observe an RFS benefit for longer maintenance regimens.

PATIENT SUMMARY

For patients with intermediate-risk non-muscle-invasive bladder cancer, bladder treatments with a solution of a drug called mitomycin C (MMC) seem to be as effective as BCG (bacillus Calmette-Guérin) in preventing recurrence after tumor removal. Further trials are needed for stronger evidence on the best MMC dose and treatment time.

Mathematical model of MMC chemotherapy for non-invasive bladder cancer treatment

Mitomycin-C (MMC) chemotherapy is a well-established anti-cancer treatment for non-muscle-invasive bladder cancer (NMIBC). However, despite comprehensive biological research, the complete mechanism of action and an ideal regimen of MMC have not been elucidated. In this study, we present a theoretical investigation of NMIBC growth and its treatment by continuous administration of MMC chemotherapy. Using temporal ordinary differential equations (ODEs) to describe cell populations and drug molecules, we formulated the first mathematical model of tumor-immune interactions in the treatment of MMC for NMIBC, based on biological sources. Several hypothetical scenarios for NMIBC under the assumption that tumor size correlates with cell count are presented, depicting the evolution of tumors classified as small, medium, and large. These scenarios align qualitatively with clinical observations of lower recurrence rates for tumor size ≤ 30[mm] with MMC treatment, demonstrating that cure appears up to a theoretical x[mm] tumor size threshold, given specific parameters within a feasible biological range. The unique use of mole units allows to introduce a new method for theoretical pre-treatment assessments by determining MMC drug doses required for a cure. In this way, our approach provides initial steps toward personalized MMC chemotherapy for NMIBC patients, offering the possibility of new insights and potentially holding the key to unlocking some of its mysteries.

Loco-regional deep hyperthermia combined with intravesical Mitomycin instillation reduces the recurrence of non-muscle invasive papillary bladder cancer

OBJECTIVES

To compare the therapeutic effects of locoregional deep hyperthermia combined with intravesical chemotherapy with those of intravesical chemotherapy alone in patients with intermediate-/high-risk non-muscle invasive bladder cancer (NMIBC). To evaluate the impact of thermal dose in hyperthermia treatment.

METHODS

We analyzed data retrieved from the medical records of patients with intermediate-/high-risk NMIBC treated with intravesical mitomycin (IM group) or locoregional deep hyperthermia combined with intravesical mitomycin (CHT group) at a single tertiary care hospital between May 2016 and June 2019. The primary and secondary endpoints were the recurrence-free survival rate and progression-free survival rate, respectively. Thermal dose was evaluated and adverse events were also recorded.

RESULTS

In total, 43 patients (CHT: 18 patients, IM: 25 patients) were enrolled. The median follow-up durations were 14 and 23 months, respectively. The recurrence rate at 12 months was significantly lower in the CHT group than in the IM group (11.1% vs. 44%, p = .048); this trend persisted at 24 months (CHT: 11.1%, IM: 48%; p = .027). The recurrence-free survival was also significantly higher in the CHT group than in the IM group (p = .028). No tumor recurrence was noted in patients who received a thermal dose of ≥4 CEM43. All adverse events were well tolerated, and there was no treatment-related mortality.

CONCLUSIONS

Intravesical chemotherapy combined with locoregional deep hyperthermia for intermediate-/high-risk papillary NMIBC can significantly decrease the recurrence rate relative to that observed after intravesical chemotherapy alone.

Adjuvant intravesical therapy based on an in vitro cytotoxicity assay in the management of superficial transitional cell cancer of the urinary bladder

OBJECTIVE

To investigate the utility of an individualized chemo/immunotherapy regimen of intravesical therapy based on the results of an assessment of in vitro cytotoxicity.

PATIENTS AND METHODS

Intravesical adjuvant chemo/immunotherapy was given to 47 patients based on the results of in vitro cytotoxicity assay of the responses of cultured autologous tumour cells to various cytotoxic drugs (mitomycin-C, doxorubicin and cisplatin) and immunomodulating agents (bacillus Calmette-Guérin, BCG and interferon-alpha2b). Intravesical therapy was given as single- or double-drug regimens according to the assay results: 16 (34%) patients showed cytotoxicity to a single drug and 31 (66%) showed maximum cytotoxicity to a combination of immunomodulators and cytotoxic agents. The efficacy of treatment in terms of tumour-free survival and recurrence rate was compared with 40 patients receiving intravesical BCG according to International Protocol (control group).

RESULTS

In the in vitro assay group, seven patients (15%) had tumour recurrence, compared to 15 (38%) in the control group (P = 0.02). In the in vitro group, one of 16 patients on a single drug and six on the double-drug regimen had a recurrence. The patients given BCG with cytotoxic drugs had no recurrences, but 29% of patients given interferon-alpha2b combinations had recurrences. Kaplan-Meier analysis showed a longer recurrence-free survival in the in vitro group (75%) than in the control group (49%) at 48 months of follow-up.

CONCLUSION

Intravesical therapy based on an in vitro cytotoxicity assay is an attempt to give individualized therapy, and to increase tumour-free survival in these patients, with no side-effects. Recurrences in seven patients in the in vitro group might be due to a defective host immune response, or to expansion of a subclone of tumour cells resistant to all treatment.