Topical Ascorbic Acid for Treatment of Squamous Cell Skin Cancer
Study Details
Study Description
Brief Summary
Randomized comparative trial of a 30% solution of ascorbic acid in 95% dimethylsulfoxide applied topically twice a day for 8 weeks vs 5% imiquimod cream in the treatment of biopsy proven squamous cell carcinomas of the skin in otherwise healthy adult patients. Outcome measure was biopsy proven resolution of the carcinoma.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
Early Phase 1 |
Detailed Description
Importance:
Skin cancer is the most common cancer in the United States, with more people diagnosed each year than all other cancers combined. Basal cell and squamous cell cancers are the most common forms with an estimated 6-7 million cases diagnosed annually. Costs of treating these cancers in the U.S. are estimated at $9-10 billion annually. Task force consensus guidelines suggest Mohs surgery as the treatment of choice, and as the single most precise and effective treatment method. However, cost and issues of cosmesis are principal disadvantages. Previous studies show the effectiveness of a topical solution of ascorbic acid in the treatment of BCC. This study extends previous work to evaluate efficacy in the treatment of SCC of the skin.
Objective:
To evaluate efficacy of a therapeutic regimen in treating squamous cell cancer, consisting of 30% ascorbic acid in 95% dimethylsulfoxide topically applied at home by patients twice a day for 8 weeks, vs 5% imiquimod cream which is an FDA approved treatment for SCC.
Design, Setting, and Participants:
This study was carried out in accordance with principles of the Declaration of Helsinki. Detailed informed consent was obtained from each patient.
Eligible participants of any age had histologically confirmed primary, previously untreated, nodular or superficial SCC. Patients with cancers larger than 2 cm or deeper than 2 mm were excluded from the study. Imiquimod was applied once daily for 5 days per week as per manufacturer instructions for treatment of SCC. Patients were randomly assigned to treatment group. Participants and outcome assessors were blinded to treatment protocol. Patients were seen at initial visit, 4 weeks, 8 weeks, and six weeks after treatment conclusion for final biopsy. The AA treatment was a solution while the IMQ a cream, however participants were simply told they would be receiving a topical treatment with instructions on how to apply, thus the blinding remained intact.
Histopathology showed 21 nodular and 8 superficial BCC subtypes upon enrollment. Thirteen patients (8 female 5 male) with a total of 15 lesions were randomized to the ascorbic acid (AA) treatment group, and 12 patients (6 female 6 male) with 14 lesions were randomized to the imiquimod group (IMQ). There was no difference in mean size of BCC in each group ( 11.4 +/-2.1 mm vs. 13.1 +/- 1.9mm). The AA group had 11 nodular and 4 superficial BCC and the IMQ group 10 nodular and 4 superficial.
Histopathology was confirmed by 2mm partial punch biopsy leaving the bulk of the BCC intact prior to treatment. Patients in the AA group were treated twice daily 7 days per week with a topical solution of 30% (w/v) ascorbic acid solution in 95% (v/v) dimethylsulfoxide (DMSO) and 5% (v/v) distilled water, while the IMQ patients received twice daily application of a commercial 5% cream 5 days per week according to manufacturer recommendations for treatment of BCC. Application was made with a small cuticle brush in the AA group. Patient compliance was high and no patient had difficulty with the application. Volume of the ascorbic acid solution applied was 0.2-0.3ml per application. Treatment was continued for 8 wks or until the lesion cleared. Subjects in the IMQ group whose lesions had failed to resolve at 8 weeks were treated for an additional 4 weeks in conformity with reports showing better outcomes with 12 weeks of treatment with IMQ ( ).
All patients had an appointment set for Mohs surgery after study enrollment, so in the event of treatment failure no further delay in definitive treatment would occur.
Repeat 2mm punch biopsy of each site was taken at the conclusion of the study. Patients were seen in follow up after 12, 24, and 30 months Interventions An 8 wk therapeutic regimen of topical 30% (w/v) ascorbic acid, 95% (v/v) dimethylsulfoxide, and 5% (v/v) distilled water applied twice daily at home, or 5% imiquimod cream applied 5/wk according to manufacturer recommendations for treating BCC.
Main Outcomes and Measures Number of lesions out that were cancer free after 8 wks of treatment.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: 30% Ascorbic Acid in DMSO Topical application twice daily of 300ul 30% (w/v) solution of ascorbic acid in DMSO |
Drug: 30% ascorbic acid in DMSO
see above
|
Outcome Measures
Primary Outcome Measures
- Lesion Resolution [8 weeks]
Number of lesions tumor free by 2 mm punch biopsy post treatment
Eligibility Criteria
Criteria
Inclusion Criteria: Presence of biopsy proven squamous cell cancer of the skin -
Exclusion Criteria: Previous history of malignancy, diabetes, immunocompromised
-
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Center for Biomedical Research,Inc. | Boise | Idaho | United States | 83706 |
Sponsors and Collaborators
- Center for Biomedical Research, Inc.
Investigators
None specified.Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- SCC_002