Variable light-dose effect on photodynamic therapy for laryngeal papillomas.
OBJECTIVE
We investigated photodynamic therapy (PDT) as an alternative treatment modality for recurrent respiratory papillomatosis. To optimize the effect of PDT, the light dose in this study was increased from 50 to 80 J/cm2. The clinical effect of these two light doses will be discussed and compared.


METHODS
Each patient's response was based on the growth rate of their papilloma before and after PDT. Disease response following 50 J/cm2 was compared with that after 80 J/cm2. The two study groups were also compared with a control group.


METHODS
Each patient received the dihematoporphyrin ether as an outpatient and underwent direct laryngoscopy and PDT at our institution.


METHODS
Twenty-eight patients (16 male and 12 female) with moderate to severe laryngeal disease and an age range of 18 months to 80 years were treated with a light dose of 80 J/cm2, 11 of those had been previously treated with 50 J/cm2. Seven patients had undergone photoactivation to the trachea.


METHODS
Twenty-four hours prior to photoactivation, patients received 2.5 mg/kg of dihematoporphyrin ether intravenously. Photodynamic therapy was given using an argon pump dye laser system.


METHODS
Reduction in disease severity greater than that achieved with 50 J/cm2.


RESULTS
For patients treated initially with 80 J/cm2, the mean rate of papilloma growth decreased by approximately 50%, the same response seen with 50 J/cm2 of treatment. No additional benefit was found for those patients initially activated at 50 J/cm2 and then re-treated at 80 J/cm2.


CONCLUSIONS
Although PDT has a beneficial effect on laryngeal papilloma growth rate, no significant change in response was obtained by increasing the light dose from 50 to 80 J/cm2.
Abramson
A L
AL
Department of Otolaryngology and Communicative Disorders, Long Island Jewish Medical Center, New Hyde Park, NY.
Shikowitz
M J
MJ
Mullooly
V M
VM
Steinberg
B M
BM
Hyman
R B
RB
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D017323:Dihematoporphyrin Ether / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006414:Hematoporphyrin Photoradiation / Q000009:adverse effects; D006801:Humans; D007223:Infant; D007822:Laryngeal Neoplasms / Q000188:drug therapy* / Q000601:surgery; D053685:Laser Therapy; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy / Q000601:surgery; D010212:Papilloma / Q000188:drug therapy* / Q000601:surgery; D010778:Photochemotherapy / Q000009:adverse effects; D011829:Radiation Dosage; D012074:Remission Induction; D014134:Tracheal Neoplasms / Q000188:drug therapy
D017323:Dihematoporphyrin Ether