Efficacy of DHE photodynamic therapy for respiratory papillomatosis: immediate and long-term results.
OBJECTIVE
Recurrent respiratory papillomatosis is a potentially life-threatening disease that affects both children and adults and can result in complete respiratory obstruction. Conventional therapies cannot prevent multiple recurrences. The authors have been evaluating photodynamic therapy (PDT) to treat this disease since 1988. This study compared the efficacy of PDT with dihematoporphyrinether (DHE) with traditional therapy.


METHODS
This was a randomized prospective trial of DHE-PDT. Patients were randomly assigned to receive one of two doses of DHE--3.25 mg/kg or 4.25 mg/kg body weight. They were compared with a concurrent control group. Disease extent was evaluated by direct laryngoscopy before treatment and over a 1-year period following treatment. Results were also compared with two historical cohorts of patients treated with lower doses of DHE.


METHODS
Eighty-one patients, ages 4 to 74 years, with moderate to severe recurrent disease were enrolled. Forty-eight received PDT and 33 in the control group were treated with conventional therapy. Both PDT groups received 50 J laser light to activate the drug. Patients received an intravenous infusion of DHE as outpatients 48 to 72 hours before treatment. During direct laryngoscopy, light (630 nm) was delivered by an argon-pumped dye laser. Tissue biopsies were analyzed for presence of human papillomavirus (HPV).


RESULTS
There was notable improvement with either drug dose over the first year. Those receiving 4.25 mg/kg DHE experienced a significantly larger decrease in papilloma growth rate. Three-year follow-up of a subset of patients confirmed that improvement was maintained. There was no impact of DHE-PDT on persistence of HPV DNA.


CONCLUSIONS
This therapy holds promise for the treatment of laryngeal papillomas.
Shikowitz
M J
MJ
Department of Otolaryngology and Communicative Disorders, Long Island Jewish Medical Center, The Long Island Campus for the Albert Einstein College of Medicine, New Hyde Park, New York 11040, USA.
Abramson
A L
AL
Freeman
K
K
Steinberg
B M
BM
Nouri
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D017323:Dihematoporphyrin Ether / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006414:Hematoporphyrin Photoradiation / Q000379:methods*; D006801:Humans; D007828:Laryngoscopy; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy* / Q000821:virology; D010212:Papilloma / Q000188:drug therapy* / Q000821:virology; D027383:Papillomaviridae; D030361:Papillomavirus Infections / Q000150:complications; D011446:Prospective Studies; D012142:Respiratory Tract Neoplasms / Q000188:drug therapy* / Q000821:virology; D016896:Treatment Outcome; D014412:Tumor Virus Infections / Q000150:complications
D000970:Antineoplastic Agents; D017323:Dihematoporphyrin Ether