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# Light: photodynamic therapy - Haygood Health

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### [Light: photodynamic therapy](/c/light)

MechanismESTABLISHEDOutcomeA/B (specific cancers)

Claimed

Light can heal tissue and kill cancer.

What holds up

Light-activated drug plus matching-wavelength laser; decades of trials for specific lesions.

What it does not show

Approved for certain skin, esophageal and lung lesions. Not a general light cure; red-light panels are not this.

Evidence for

NCI PDQ summary on photodynamic therapy. Specific trial citations to be added and verified.

Sources

PENDING NCI PDQ summary on photodynamic therapy. Specific trial citations to be added and verified..

## Grade history (append-only)

Every grade change is kept, never overwritten, so the current grade and every prior one stay visible.

Mechanism gradeJustificationGraded byStateGraded at

ESTABLISHEDLight-activated drug plus matching-wavelength laser; decades of trials for specific lesions.seeddisplayed2026-09-03T21:29:06.036Z

Outcome gradeJustificationGraded byStateGraded at

A/B (specific cancers)Approved for certain skin, esophageal and lung lesions. Not a general light cure; red-light panels are not this.seeddisplayed2026-09-03T21:29:06.037Z

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