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1.
Clin Cancer Res ; 24(13): 3026-3035, 2018 07 01.
Article in English | MEDLINE | ID: mdl-29593028

ABSTRACT

Purpose: Actinic keratoses (AK) are precancerous lesions that can progress to squamous cell carcinoma. Photodynamic therapy (PDT) and topical 5-fluorouracil (5FU) are commonly used agents for AK. Empirical reports suggest that combining them can improve the therapeutic response. However, the optimal combined regimen was not clear in terms of proper sequence, timing, and mechanism. This clinical study explored mechanisms of action for neoadjuvantal 5FU and PDT for treatment of AK.Patients and Methods: A bilaterally controlled trial (17 patients) was performed. One side of the body (face, scalp, forearms) received 5FU pretreatment for 6 days, whereas the other side served as no-pretreatment control. Methylaminolevulinate cream was applied to both sides for 3 hours, and protoporphyrin IX (PpIX) levels were measured by noninvasive fluorimetry and skin biopsy. After red light illumination, lesion clearance was assessed at 3, 6, 9, and 12 months after PDT.Results: PpIX levels were increased 2- to 3-fold in 5FU-pretreated lesions versus controls. Altered expression of heme-synthetic enzymes (coproporphyrinogen oxidase and ferrochelatase) and induction of p53 were observed, probably accounting for increased PpIX and subsequent cancer cell death. Relative clearance rates after PDT with or without 5FU pretreatment were 75% versus 45% at 3 months, and 67% versus 39% at 6 months, respectively; these differences were statistically significant.Conclusions: Serial 5FU and PDT improve AK clearance by at least two mechanisms, enhanced photosensitizer accumulation and p53 induction. Because 5FU and PDT are FDA-approved modalities, the combined regimen can be readily employed in clinical practice to reduce AK burden and reduce SCC risk. Clin Cancer Res; 24(13); 3026-35. ©2018 AACR.


Subject(s)
Fluorouracil/pharmacology , Keratosis, Actinic/etiology , Keratosis, Actinic/metabolism , Protoporphyrins/metabolism , Apoptosis/drug effects , Biomarkers , Biopsy , Heme/metabolism , Humans , Keratosis, Actinic/pathology , Keratosis, Actinic/therapy , Photochemotherapy , Photosensitizing Agents/pharmacology , Skin/drug effects , Skin/metabolism , Skin/pathology
2.
J Cutan Pathol ; 39(8): 741-6, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22804092

ABSTRACT

Cutaneous collagenous vasculopathy is a rare microangiopathy of superficial dermal blood vessels. Patients present with telangiectatic macules, predominantly on the extremities. A skin biopsy specimen is necessary to distinguish cutaneous collagenous vasculopathy from generalized essential telangiectasia. Microscopically, cutaneous collagenous vasculopathy resembles the superficial telangiectasias of generalized essential telangiectasia but additionally shows hyaline material in thickened vessel walls. The amorphous pink material is periodic acid-Schiff-positive and resistant to diastase. We describe a series of four patients with cutaneous collagenous vasculopathy and highlight its clinical and histopathologic features.


Subject(s)
Dermis/pathology , Microvessels/pathology , Skin Diseases, Vascular/pathology , Adult , Aged , Amylases/metabolism , Biomarkers/metabolism , Dermis/blood supply , Dermis/metabolism , Diagnosis, Differential , Female , Glycosaminoglycans/metabolism , Humans , Hyalin/metabolism , Male , Microvessels/metabolism , Middle Aged , Periodic Acid-Schiff Reaction , Skin Diseases, Vascular/metabolism , Telangiectasis/diagnosis
3.
J Biomed Opt ; 15(5): 051607, 2010.
Article in English | MEDLINE | ID: mdl-21054081

ABSTRACT

Topical 5-aminolevulinic acid (ALA) is widely used in photodynamic therapy (PDT) of actinic keratoses (AK), a type of premalignant skin lesion. However, the optimal time between ALA application and exposure to light has not been carefully investigated. Our objective is to study the kinetics of protoporphyrin IX (PpIX) accumulation in AK after short contact ALA and relate this to erythemal responses. Using a noninvasive dosimeter, PpIX fluorescence measurements (5 replicates) were taken at 20-min intervals for 2 h following ALA application, in 63 AK in 20 patients. Data were analyzed for maximal fluorescent signal obtained, kinetic slope, and changes in erythema. Our results show that PpIX accumulation was linear over time, becoming statistically higher than background in 48% of all lesions by 20 min, 92% of lesions by 1 h, and 100% of lesions by 2 h. PpIX accumulation was roughly correlated with changes in lesional erythema post-PDT. We conclude that significant amounts of PpIX are produced in all AK lesions by 2 h. The linear kinetics of accumulation suggest that shorter ALA application times may be efficacious in many patients. Noninvasive fluorescence monitoring of PpIX may be useful to delineate areas of high PpIX accumulation within precancerous areas of the skin.


Subject(s)
Aminolevulinic Acid/administration & dosage , Keratosis, Actinic/drug therapy , Keratosis, Actinic/metabolism , Photochemotherapy/methods , Protoporphyrins/biosynthesis , Administration, Topical , Aged , Erythema/etiology , Erythema/pathology , Female , Fluorescence , Humans , Keratosis, Actinic/pathology , Male , Middle Aged , Photobleaching , Treatment Outcome
4.
J Empir Res Hum Res Ethics ; 4(3): 73-87, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19754237

ABSTRACT

PARENTS OF SERIOUSLY ILL CHILDREN FACE difficult decisions when standard therapies are limited or ineffective. In their search for information, they may turn to websites created by other parents facing similar experiences. We conducted a qualitative content analysis of 21 websites created by families with children affected by cancer or genetic disease, two serious conditions with a range of treatment and clinical trial options. Our research questions address how parent authors portray serious pediatric illness, available options, parties to decision making, and sources of influence. In addition, we examine what these sites reveal about family vulnerability to various risks, particularly the risk of misunderstanding the distinction between standard treatment and research and the risk of overestimating the likely benefits of research participation, as well as whether vulnerability varies by type of condition. Our results demonstrate typically favorable views on research, but with inadequate distinctions between research and treatment and a complex set of trade-offs in consideration of research risks and potential benefits. While portraits of vulnerability emerge for both parents and children, so do portraits of strength and resilience. As a result, parents describe frustration with both under- and overprotection from research participation. Our discussion of these findings clarifies the potential for parent-authored websites to inform and influence families considering research and treatment options for their seriously ill children.


Subject(s)
Genetic Diseases, Inborn/psychology , Internet , Neoplasms/psychology , Parents/psychology , Social Support , Child , Genetic Diseases, Inborn/therapy , Humans , Neoplasms/therapy
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