Acute excisional wounds treated with a tissue-engineered skin (Apligraf).

BACKGROUND: Tissue-engineered products are usually composed of living cells and their supporting matrices that have been grown in vitro, using a combination of engineering and life sciences principles. Apligraf is a bilayered product composed of neonatal-derived dermal fibroblasts and keratinocytes, and Type I bovine collagen. OBJECTIVE: To evaluate in a prospective, multicentered open study, the effects of tissue therapy with a tissue-engineered skin (Apligraf) with partial or full-thickness excisional wounds. METHODS: One hundred and seven patients participated in this study. The tissue-engineered skin was applied once, immediately after excisional surgery, usually for skin cancer, and patients were followed for up to one year. RESULTS: The safety results were impressive, with no clinical or laboratory evidence of rejection. Clinically, graft persistence was good to excellent in 77 of 105 (73.3%) of patients at one week, falling to 56.6% and 53.6% at two weeks and one month respectively. CONCLUSION: To date, this is the largest experience with a tissue-engineered skin product in acute wounds, and this study suggests that tissue therapy may be safe and useful.

Correlation of histologic subtypes of primary basal cell carcinoma and number of Mohs stages required to achieve a tumor-free plane.

BACKGROUND: Certain histologic subtypes of basal cell carcinoma (BCC) behave more aggressively and require more aggressive treatment. OBJECTIVE: The aim of this study was to see whether certain subtypes of BCC require more Mohs stages to achieve tumor-free margins. METHODS: A retrospective study of 342 primary BCCs treated with Mohs micrographic surgery (MMS) was performed identifying the histologic subtype of BCC present and the number of stages required to clear the tumor. RESULTS: The aggressive subtypes (infiltrative, morpheaform, micronodular, and mixed) were most frequently found when high numbers of Mohs stages were required for cure. CONCLUSION: The more aggressive subtypes of BCC require more MMS stages to achieve tumor-free margins, which is consistent with the concept that these subtypes usually require more aggressive treatment from the start.

Complications of cutaneous surgery in patients who are taking warfarin, aspirin, or nonsteroidal anti-inflammatory drugs.

BACKGROUND AND DESIGN: No controlled studies exist with regard to the risks of continuing therapy with warfarin sodium or platelet inhibitors or the benefits of briefly discontinuing therapy with these agents in patients who are undergoing cutaneous surgical procedures. Our objective was to determine the frequency of complications of cutaneous surgery in patients who were receiving warfarin or platelet inhibitors and to evaluate whether preoperative discontinuation reduces complications. A retrospective, controlled study was performed of complications of excisional and Mohs micrographic surgery in 653 patients who were being treated with warfarin or platelet inhibitors or with their medications being briefly withheld. RESULTS: Severe complications of cutaneous surgery in patients who are taking warfarin or platelet inhibitors are uncommon, occur in 1.6% of cases, and are not significantly increased compared with complications in control subjects. Furthermore, there was no statistically significant reduction in the rates of severe complications in patients who had their medications preoperatively held. CONCLUSION: Cutaneous surgery in patients who receive warfarin or platelet inhibitors is associated with a low risk of severe complications, not significantly reduced by brief preoperative discontinuation.

Lack of selectivity of protoporphyrin IX fluorescence for basal cell carcinoma after topical application of 5-aminolevulinic acid: implications for photodynamic treatment.

Clinical trials of topical ALA in photodynamic therapy (PDT) of basal cell carcinoma (BCC) show significant recurrence rates. Exogenous 5-aminolevulinic acid (ALA) is converted by intracellular enzymes to photoactive protoporphyrin IX (PpIX) in human tissues. PpIX generates cytotoxic singlet oxygen when irradiated with visible light in the 400-640 nm range. To evaluate variability and heterogeneity in PpIX production by tumors in such trials, and to assess the usefulness of PpIX for marking skin tumors, we measured PpIX fluorescence distribution in BCC after topical application of 20% ALA cream. ALA cream was applied under occlusion for periods ranging from 3 to 18 h (average 6.9 h, SD 4 h) to 16 BCCs. ALA conversion to PpIX in the BCCs was assessed by in vivo photography, ex vivo video fluorescence imaging, and fluorescence microscopy. External macroscopic PpIX fluorescence, as assessed by in vivo and ex vivo imaging, correlated with the clinical presence of BCC. Examination by a digital imaging fluorescence microscope revealed inter- and intratumor fluorescence variability and heterogeneity. PpIX fluorescence corresponding to full tomor thickness was found in six superficial and four nodular tumors, and partial-thickness fluorescence was observed in five nodular tumors, but no PpIX fluorescence was observed in some areas of superficial, nodular and infiltrating tumors. In a significant number of nodular and infiltrating BCCs, topical ALA appeared to provide little or no PpIX in deep tumor lobules. In addition, no selectivity for tumor tissue versus normal epidermis was seen. The grossly brighter external PpIX fluorescence over tumors may be due, therefore, to enhanced penetration through tumor-reactive stratum corneum and to the tumor thickness.(ABSTRACT TRUNCATED AT 250 WORDS)

Wound healing.

Wound healing is a dynamic biologic process of repairing insults to the integumentary system. It is commonly divided into three phases: inflammatory, proliferative, and maturation. Each phase has unique cellular and substance constituents without which it cannot progress normally. A large variety of factors may influence any part of wound healing, including local factors such as bacteria, oxygen tension, and bleeding, and systemic factors such as the mental and physical health of the patient. There are also extrinsic factors that can be influenced by the caretakers of the wound to enhance wound healing. Areas of intervention include using antiseptic technique when one is dealing with the wound, using good surgical technique, choosing the appropriate wounding method and repair for the individual patient, and using antibiotics and special wound dressings. Modern science and technology are giving us new insights into wound healing and leading us to exciting new ways of influencing it, including the topical use of growth factors, artificial skins, cultured epithelium with and without dermal components, and electrical stimulation. The future of wound healing holds a better understanding of the complexities of the physiologic events that occur and a translation of that into a biologically active and interactive wound care.

Metastatic lentigo maligna melanoma.

An elderly woman presented with an advanced and ultimately lethal lentigo maligna melanoma after ignoring a precursor lesion present for several decades. Lentigo maligna melanoma can be lethal in the elderly. Early detection and treatment are warranted.

Immunologic detection of markers of keratinocyte differentiation. Its use in neoplastic and preneoplastic lesions of skin.

We examined seven invasive squamous cell carcinomas, five squamous cell carcinomas in situ, four keratoacanthomas, two actinic keratoses, and two seborrheic keratoses by indirect immunofluorescence. We used a panel of three antibodies: one directed against filaggrin, one against involucrin, and one against peptidylarginine deiminase. Anti-involucrin stained all the lesions studied, but the pattern within a given category of lesions was variable and consistent differences between the categories were not observed. Similarly, the antibodies against peptidylarginine deiminase and filaggrin were not able to distinguish differences between the various types of tumors. We conclude that in tumors of epidermis, benign or malignant, products of differentiation are expressed independently of histologic atypia or clinical aggressiveness. Therefore, markers of differentiation do not appear to be reliable indexes for distinguishing benign from malignant lesions.