A phase‐1 study of sequential mitomycin C and 5–aminolaevulinic acid‐mediated photodynamic therapy in recurrent superficial bladder carcinoma

Abstract

RESULTSMitomycin C instillation was followed by ALA concentrations of 6%, 8% or 10%; there was no effect on toxicity. The light dose, at a wavelength of 635 nm, was increased from zero to 25 J/cm 2 , with the upper fluences producing transient symptoms. There were no episodes of skin photosensitivity or systemic toxicity. A total fluence of 25 J/cm 2 represented the upper light dose for the tolerability of this procedure by patients. There were no persistently high urinary symptom scores or reduction in functional bladder capacity up to ≥ 24 months of followup. In this group, cumulative tumour recurrences were none at 4, two at 8, six at 12, nine at 18 and 11 at 24 months after PDT, respectively. CONCLUSIONSequential mitomycin C and ALA-PDT is a safe and well tolerated treatment, with potential for managing difficult-to-control superficial transitional cell carcinoma and carcinoma in situ of the bladder .

Oxygen Effects in Photodynamic Therapy

“…Several methods have been proposed to increase tumor oxygenation: (1) breathing hyperbaric oxygen, (2) using oxygen-carrying fluorocarbons combined with carbogen (95% oxygen) breathing, (3) using nicotinamide injection and carbogen breathing, (4) using oxygen-releasing substances, (5) modulating the oxygen binding capacity of hemoglobin, (6) decreasing the respiration rate, (7) increasing the oxygen solubility, (8) using blood flow modifiers, and (9) destroying hypoxic cells with bioreductive drugs or hypothermia [50]. Several of these methods have been exploited for PDTwith promising experimental and clinical results [51][52][53][54][55][56].…”

Early bladder cancer: concept, diagnosis, and management

“…79 Two large studies using ALA achieved 29%-52% recurrence-free rates at 24-36 months without severe side effects. 82,83 A report on a phase 1 study of PDT using sequential mitomycin C and ALA suggested that recurrence occurred in 56% of the patients at 24 months after PDT without significant toxicity. 83 …”

Photodynamic Therapy in Oncology

“…ALA PDT given as a single treatment, or in combination with mitomycin C, resulted in complete response (CR) rates of 40%-52% at 18-24 months without persistent reduction in bladder capacity [55][56][57].…”