NEW EMERGING CANCER TREATMENTS

• Interstitial photodynamic therapy (iPDT)

A local treatment that uses 5-aminolevulinic acid (5-ALA) to create protoporphyrin IX, which is then irradiated with 635 nm wavelength light. iPDT has been used to treat brain tumors for over 30 years and is considered safe and effective, especially for high-grade gliomas. A systematic review found that iPDT has a 92% tumor response rate, a median progression-free survival of 14.5 months for de novo lesions and 14 months for recurrent lesions, and an overall mortality rate of 1%. Side effects can include transient health restrictions like aphasia, but brain tumor patients often have other risk factors for thromboembolic events.

• Immuno-photodynamic therapy (IPDT)

A noninvasive treatment that uses photosensitizers (PSs) to stimulate the immune response and treat cancer. IPDT combines PDT with immunotherapy to induce immunogenic cell death (ICD), a type of regulated cell death that can activate the immune system. The goal is to achieve a systemic immune response and prevent cancer recurrence. IPDT can use a variety of PSs, including transition metal complexes, porphyrins, phenothiazinium dyes, BODIPY, cyanine dyes, and organic semiconducting photosensitizers.

Both of these therapies are promising modalities in the fight against cancer.