A centimeter here, a centimeter there: does it matter?
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Dermatologic Surgical Procedures↗
Biomedical subjects
T M Johnson
Publications and source records attributed to T M Johnson.
Current therapy for cutaneous melanoma.
We review the current therapy for melanoma. The diagnosis, prognostic variables, staging, treatment, and follow-up guidelines for cutaneous melanoma are reviewed from the earliest to the most advanced stages. New guidelines for margins are discussed. A new, evolving, innovative radiographic technique, positron emission tomography using 2-fluorine-18-fluoro-2-deoxy-D-glucose, may be useful to identify subclinical nodal and visceral disease. Recent advances with respect to tumor vaccines, gene therapy, immunotherapy, and interleukin 2 as well as current concepts regarding lymph node dissection are discussed.
Humans↗
Malignant melanoma of the foot and ankle.
The records of sixty patients who had a malignant melanoma of the foot or ankle were reviewed retrospectively to determine the clinical features, prognostic factors, and distinguishing characteristics. Fifty-seven patients were white and three were black. There were forty-two women and eighteen men (a female-to-male ratio of 2.3 to 1). The mean age at the time of presentation was fifty-seven years (range, twenty-two to eighty-three years). The most common site of involvement was the plantar aspect of the foot. The mean duration of follow-up was forty-five months (range, three to 144 months). Kaplan-Meier life-table analysis revealed an over-all five-year survival rate of 63 per cent and an over-all ten-year survival rate of 51 per cent. The mean duration of survival for the patients who had a plantar or subungual lesion was significantly shorter than that for the patients who had a lesion at another site on the dorsal aspect of the foot or on the ankle (forty-seven compared with seventy-two months) (p = 0.02). The mean depth of the lesion, according to the criteria of Breslow, was 3.03 millimeters, and the mean level, according to the classification of Clark et al., was IV. According to the classification of the American Joint Commission on Cancer, forty-three patients had stage-I or II (local) disease, thirteen had stage-III disease (nodal or in-transit disease, defined as cutaneous or subcutaneous metastases more than two centimeters from the primary tumor but not beyond the regional lymph nodes), and four had stage-IV disease (distant visceral metastases) at the time of presentation. Lesions at plantar and subungual sites were also associated with a higher prevalence of clinical misdiagnosis compared with lesions on the dorsal aspect of the foot or on the ankle (p = 0.02). The misdiagnoses included a benign nevus (one patient), a paronychia (one patient), a pyogenic granuloma (two patients), a plantar wart (three patients), a ganglion cyst (one patient), a blister (two patients), and a traumatic lesion (five patients).(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Biopsy techniques for skin, soft-tissue, and bone neoplasms.
This article discusses important aspects of the biopsy of neoplasms in skin, soft tissues, and bone. There are a variety of clinical conditions in which specific biopsy techniques are indicated. Inappropriate biopsy of tumors in these sites may compromise subsequent definitive therapy.
Biopsy↗
Technical aspects of prolonged scalp expansion.
Tissue expansion offers the reconstructive surgeon a better option than the conventional methods of skin grafts or the transfer for non-hair-bearing, regional or microsurgical flaps for reconstructing large defects that cannot be repaired with adjacent hair-bearing flaps. Aspects of preoperative planning and technical factors of scalp expansion are presented to assist the clinician in managing these difficult reconstructive challenges.
Adolescent↗
Increased expression of stromelysin-3 in basal cell carcinomas.
We examined the expression of two groups of matrix metalloproteinases (MMPs), stromelysin and interstitial collagenase, in human skin cancer by northern blot analysis and in situ hybridization. Stromelysin-3 (ST-3) mRNA was overexpressed more than tenfold in 17 of 19 (89%) specimens of basal cell carcinoma (BCC) but in only three of 13 (23%) cutaneous squamous cell carcinomas (SCCs). Stromelysin-1 and -2 (ST-1/2) mRNA was overexpressed in three of 19 (16%) BCC and three of 13 (23%) SCC. Collagenase mRNA was overexpressed in nine of 19 (47%) BCC and three of 13 (23%) SCC. No mRNA for ST-3, ST-1/2, or collagenase was detected by northern analysis in 21 specimens of adjacent normal skin. Because of these findings, we examined the specific location of the ST-3 mRNA in BCC specimens by in situ hybridization. ST-3 mRNA was particularly abundant in the characteristic stroma adjacent to the invasive basaloid tumor islands of the BCC and absent in the malignant cells. Moreover, ST-3 mRNA was expressed and induced by phorbol ester treatment in adult dermal fibroblasts but not in keratinocytes. In vitro studies have shown that MMPs are involved in the degradation of extracellular matrix molecules. Our finding of ST-3 mRNA overexpression in 17 of 19 (89%) BCC specimens is consistent with a role for this molecule in local invasion of stroma by BCC. Our in situ hybridization data suggested that while ST-3 is not expressed by malignant basal cells themselves, these tumor cells may induce the expression of ST-3 in adjacent nonmalignant stromal elements such as fibroblasts.
Blotting, Northern↗
Increased expression of matrix metalloproteinase-3 (stromelysin-1) in cultured fibroblasts and basal cell carcinomas of nevoid basal cell carcinoma syndrome.
Nevoid basal cell carcinoma syndrome (NBCCS), an autosomal dominant disorder, is characterized by the development of numerous cutaneous basal cell carcinomas (BCCs). To better characterize this disorder, we examined the expression of matrix metalloproteinase-3 (MMP-3; also known as stromelysin-1) in BCC tumor specimens, adjacent normal skin, and fibroblasts isolated from the normal-appearing skin of NBCCS patients. Three of three BCC tumors obtained from NBCCS patients overexpressed MMP-3 mRNA. In contrast, only 25% of BCC specimens in patients without NBCCS demonstrated overexpression of MMP-3 mRNA. Moreover, fibroblasts isolated and cultured from all nine uninvolved skin specimens of NBCCS patients overexpressed MMP-3 mRNA. MMP-3 mRNA was not detected or was detected at very low levels in normal skin and fibroblast cultures isolated from normal skin in nonsyndrome patients.
Amino Acid Isomerases↗
Management of linear verrucous epidermal nevus with topical 5-fluorouracil and tretinoin.
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Administration, Topical↗
Utility of the subcutaneous hinge flap in nasal reconstruction.
The subcutaneous pedicle hinge flap provides excellent reconstruction of deep defects of the lateral base and caudal sidewall of the nose that extend into the cheek. The indications, flap design, and operative technique are described.
Cheek↗
Use of topical nonsteroidal anti-inflammatory drugs in excimer laser photorefractive keratectomy.
Nonsteroidal anti-inflammatory drugs (NSAIDs) produce potent analgesic, antipyretic, and anti-inflammatory effects. We studied postoperative pain in 97 consecutive patients having photorefractive keratectomy (PRK) by an excimer laser with different topical NSAID protocols. Treatment with topical homatropine hydrobromide, either diclofenac sodium (Voltaren Ophthalmic) or ketorolac tromethamine (Acular), and a soft contact lens was most effective in achieving post-PRK analgesia. We also studied post-PRK myopic regression in 68 consecutive patients and found that flurbiprofen sodium (Ocufen), when added to topical steroid protocols, significantly reduced myopic regression for one year postoperatively more than steroids alone or steroids and diclofenac sodium. Diclofenac, used with topical steroids, had less of an additive effect on myopic regression than did flurbiprofen. Topical NSAIDs are useful adjuncts to PRK therapy, both to eliminate postoperative pain and to control post-PRK myopic regression.
Administration, Topical↗
Unusual basal cell carcinomas.
The typical features of basal cell carcinoma are well recognized. However, manifestations of uncommon and unusual basal cell carcinomas are less well known. In this review, unusual basal cell carcinomas are described based on their clinical characteristics, histologic appearance, behavior, and treatment.
Age Factors↗
Clinical improvement following dermabrasion of photoaged skin correlates with synthesis of collagen I.
BACKGROUND AND DESIGN: The ability of superficial dermabrasion to improve clinical features of photoaged skin is well known, but the specific biological mechanisms involved are poorly understood. The so-called repair zone, as visualized by routine histologic examination, has been attributed to new collagen formation within the papillary dermis and may be responsible for clinical improvement following dermabrasion. We investigated molecular and histologic events occurring in dermabraded skin and correlated them with clinical improvement. Ten photoaged patients (mean age, 59 years) underwent facial dermabrasion to the level of the papillary dermis. Clinical severity of photoaging was graded in a blinded manner at baseline and 12 weeks after dermabrasion. Biopsy specimens obtained at baseline and 3 and 12 weeks after dermabrasion were analyzed histologically and by in situ hybridization for fibroblast procollagen I mRNA, immunohistologically and by Western blotting with a monoclonal antibody specific for the aminoterminal cleavage site of procollagen I. RESULTS: Masson's trichrome staining demonstrated an increase in collagen from baseline (as an upper dermal band in the dermabrasion "repair zone") at 3 and 12 weeks' postdermabrasion. Immunohistologic examination demonstrated papillary dermal fibroblast staining for procollagen I at baseline that increased by threefold at 3 weeks' postdermabrasion and by 1.5-fold at 12 weeks' postdermabrasion. Western blotting demonstrated an average-fold increase in pN collagen I of 4.2 +/- 1.5 at 3 weeks and of 2.7 +/- 0.7 at 12 weeks. By in situ hybridization, baseline levels of procollagen I mRNA in papillary dermal fibroblasts increased sixfold at weeks 3 and 12 postdermabrasion. Increase in procollagen I mRNA correlated with clinical improvement, ie, reduction in wrinkling. CONCLUSION: Superficial dermabrasion clinically improves photoaged skin, and this improvement correlates strongly with increased collagen I gene expression.
Aged↗
Basic suture materials and suturing techniques.
There is a need for surgeons to be able to make a logical decision regarding which suture materials to use in a given clinical situation because the choice of wound-closure materials may make a difference in wound healing and the ultimate functional and cosmetic result obtained. This article will review the basic physical, handling, and tissue-reaction characteristics of commonly used suture materials. Basic suturing techniques are also reviewed. Knowledge of multiple suturing techniques provides versatility, individuality, and optimal closure of surgical wounds.
Absorption↗
An insulin-responsive element in the pancreatic enhancer of the amylase gene.
We have identified a distinct insulin-responsive element (IRE) located within the pancreatic enhancer of the mouse amylase gene Amy-2.2. A 30-base pair (bp) fragment was previously shown to be sufficient to transfer insulin response to a heterologous promoter. The 30-bp fragment overlaps the tissue-specific pancreatic enhancer that binds the putative transcriptional activator PTF1. To determine whether enhancer and IRE activities could be separated, we introduced three 10-base pair substitutions into the 30-bp region. The mutated regulatory regions were cloned upstream of a heterologous promoter and transferred to transgenic mice. Mutants 1 and 2 retained PTF1 binding activity and insulin response. Mutant 3 retained PTF1 binding, but was defective in insulin response. The results indicate that the IRE is functionally distinct from the PTF1-binding site, although the two overlap physically. In contrast to the wild-type gene, mutant 3 is characterized by constitutive expression in diabetic animals, suggesting that a binding site for a repressor has been destroyed. A nuclear protein with affinity for the IRE was detected in normal and diabetic pancreas. This protein does not bind mutant 3, suggesting that it may be involved in negative regulation of amylase in diabetic pancreas.
Amylases↗
Merkel cell carcinoma.
Merkel cell carcinoma is a malignant neuroendocrine tumor with features of epithelial differentiation. Biologically aggressive, it may be difficult to diagnose and, particularly in its late stages, even more difficult to treat effectively. This article addresses what is known and what is still controversial about the histogenesis, diagnosis, and management of Merkel cell carcinoma and the structure and function of the Merkel cell from which it is believed to be derived. The incidence, clinical presentation and diagnosis, ultrastructure, immunocytochemistry, treatment, and prognosis of this tumor will be discussed.
Carcinoma, Merkel Cell↗
Microcystic adnexal carcinoma.
Microcystic adnexal carcinoma is a rare cutaneous neoplasm characterized by invasive, relentless, and destructive local growth. The incidence of perineural invasion and tumor recurrence is high. We report two cases of microcystic adnexal carcinoma with typical clinical features. The use of formalin-fixed, paraffin-embedded horizontal Mohs sections is described in one case. We also review the current concepts and management of microcystic adnexal carcinoma.
Aged↗
Histology and physiology of tissue expansion.
BACKGROUND: Tissue expansion is a concept based on the skin's natural ability to stretch in response to an underlying force. OBJECTIVE: The purpose of this article is to review the histological and physiological changes that occur within the soft tissue and underlying structures during tissue expansion. METHODS: An extensive search of the literature reviewing these changes is summarized herein. RESULTS: Conventional tissue expansion may result in epidermal hypertrophy, decreased dermal, muscle, and adipose thickness, and bone resorption. A vascular capsule and angiogenesis provides a highly vascular flap and improves flap viability. Few soft tissue changes occur during rapid tissue expansion. The ability of the skin to increase in surface area during conventional tissue expansion is primarily because of biological tissue creep. Rapid expansion may result from mechanical tissue creep. CONCLUSION: Many soft tissue changes occur during tissue expansion. Most of these changes return to the pre-expansion state over time following discontinuation of the expansion process.
Animals↗
Complications of tissue expansion.
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Dermatologic Surgical Procedures↗