C.M. Lawrence

Trans-gender induction of hair follicles

Human follicle cells can be induced to grow in an incompatible host of the other sex.

Measurement of involved surface area in patients with psoriasis

Three methods of measuring the surface area of the involved skin were compared in 10 patients with psoriasis. Using the rule of nines, four untrained observers estimated the average extent of psoriasis as 20, 14, 23 and 33% of the body surface area. Measuring the area of tracings of plaque outlines using image analysis gave a mean involved surface area of 9% and image analysis of whole body photographs gave a mean value of 7%. We conclude that untrained observers using the rule of nines will overestimate the extent of psoriasis and that image analysis of whole body photographs is comparable to that of traced outlines.

Effect of aspirin and nonsteroidal antiinflammatory drug therapy on bleeding complications in dermatologic surgical patients

BACKGROUND Aspirin and nonsteroidal antiinflammatory drugs (NSAIDs) inhibit platelet cyclooxygenase activity, resulting in altered platelet function and thus potentially enhanced bleeding. OBJECTIVE We examined the frequency of operative bleeding complications in dermatologic surgical patients taking these drugs and the value of template bleeding time estimates in predicting this complication. METHODS Bleeding time was measured with and without therapy in 23 patients and was correlated to bleeding complications after skin tumor or benign lesion excision in 40 patients taking aspirin, 21 taking NSAIDs, and 20 taking neither drug. RESULTS Bleeding time dropped significantly (p < 0.01) when patients stopped therapy for at least 5 days (median, 7 days), although bleeding time was prolonged in only 6 of 16 patients taking aspirin and 2 of 7 taking NSAID. In patients who continued antiplatelet drugs during surgery, bleeding time was prolonged in 8 of 40 patients taking aspirin and in 1 of 21 treated with NSAIDs. Excessive intraoperative bleeding occurred in three aspirin-treated patients, all of whom had a prolonged bleeding time, compared with none of those with normal bleeding times (p < 0.001, Fishers exact probability test) and with none of those taking NSAIDs. Postoperative ooze requiring a dressing replacement occurred in one NSAID-treated patient and in three patients taking neither drug. CONCLUSION Bleeding time is increased by aspirin and NSAID therapy but is prolonged beyond the normal range in only approximately 25% of aspirin-treated and 10% of NSAID-treated patients. Intraoperative bleeding complications occurred only in patients receiving aspirin who had a prolonged bleeding time. Postoperative oozing occurred only in NSAID-treated and in untreated patients and thus is probably unrelated to antiplatelet therapy. Patients with a normal bleeding time can continue aspirin or NSAID therapy before dermatologic surgery.

The relevance and effect of amalgam replacement in subjects with oral lichenoid reactions

In this study we examined the prevalence of mercury hypersensitivity in patients with oral lichenoid reactions (OLR) and the effect of amalgam replacement in subjects with amalgams adjacent to OLR irrespective of their mercury sensitivity status. One hundred and ninety‐seven patients with oral problems were examined: 109 with OLR. 22 with oral and generalized lichen planus. and 66 with other oral diagnoses, including aphthous ulcers and orofacial granulomatosis. Nineteen per cent of patients with OLR reacted to mercury on patch testing, significantly more than in those with generalized lichen planus (0%) and in those with other oral diagnoses (3%). Twenty‐two patients with OLR and adjacent amalgams had amalgam replacement and. in 16 of 17 mercury‐positive subjects and three of four mercury‐negative subjects, the OLR resolved after amalgam removal. In conclusion, we found a significantly increased prevalence of mercury hypersensitivity in patients with localized OLR in comparison to subjects with other oral problems. Amalgam replacement resulted in resolution of OLR in the majority of patients with amalgams adjacent to OLR irrespective of their mercury sensitivity status.

Micrographic surgery for subungual squamous cell carcinoma

Eight patients were treated for subungual squamous cell carcinoma (4 female, 4 male; mean age 61 years). History of disease ranged from 9 months to 14 years (mean 4.7 years). Outpatient surgery under local anaesthetic was performed using Mohs micrographic surgery and formalin-fixed histological specimens. Tumour clearance was achieved after 2-6 procedures (median 3) over a mean period of 6.9 days. In all cases the wounds were allowed to heal by secondary intention and the distal phalanx was preserved. During a mean follow-up period of 3.1 years (range 0.5-6), no recurrence was seen and involved digits remained functional. Mohs micrographic surgery can provide a valuable alternative to amputation for subungual squamous cell carcinoma.

Melanomas arising from naevi and de novo melanomas--does origin matter?

Background  It is widely accepted that some melanomas arise from pre‐existing naevi, while others appear de novo. The proportions involved and the effect of melanoma origin on prognosis is unclear.

Inhibition of dithranol inflammation by free-radical scavengers

Dithranol (anthralin) inflammation of forearm skin was completely inhibited by various scavengers of free radicals of the oxygen species. It is concluded that dithranol inflammation is initiated by formation of free radicals; these may act through lipid peroxidation and production of inflammatory endoperoxides or by a more direct mechanism.

Relation between size of skin excision, wound, and specimen

BACKGROUND Skin wounds differ in shape and size compared with the planned excision, and skin shrinks after excision and fixation. OBJECTIVE This study was designed to quantify and to analyze the differences between the size and shape of the planned excision, wound, and specimen. METHODS Eighty-six patients with 93 benign or malignant skin tumors were prospectively studied. Length and width measurements were made of the lesion, planned surgical excision, postexcision wound, and prefixation and postfixation specimens. The results were analyzed to identify the effects of patient age and sex, and lesion type and site. RESULTS Wound size was larger than planned excision size in 90% of wounds, and this effect was greatest in young patients and at trunk and limb sites. Excision and fixation caused the specimens to shrink so that the postfixation area was on average 48% of the planned excision area; benign tumors shrank more than malignant tumors. CONCLUSION Significant differences among planned excision, wound, and specimen sizes are influenced by patient age and by lesion site and type. These results demonstrate that wound size is not equivalent to tumor size, a conclusion often made in Mohs surgery. Furthermore, assessment of tumor clearance margins from fixed tissue does not reflect in vivo clearance margins.

The use of a spectrophotometric intracutaneous analysis device in the real‐time diagnosis of melanoma in the setting of a melanoma screening clinic

Background  Skin imaging devices to aid melanoma diagnosis have been developed in recent years but few have been assessed clinically.

A retrospective study of outcome of Mohs’ micrographic surgery for cutaneous squamous cell carcinoma using formalin fixed sections

The surgical management of recurrent or large squamous cell carcinoma (SCC) can be challenging as tumours often extend beyond visible margins. Micrographic surgery is a potentially effective method of ensuring complete clearance of tumour. A retrospective study of all cases of SCC treated by micrographic surgery in this department between 1986 and 1996 has been done. Sixty‐one patients were treated using a formalin‐fixed paraffin‐embedded tissue technique with a median follow‐up of 4 years. In two cases there was local recurrence and in three others metastasis to local lymph nodes. The overall cure rate was 92% (56 of 61), which compares favourably with published series using chemosurgery and frozen tissue techniques. The results show that this technique of micrographic surgery is a satisfactory and cost‐effective alternative to conventional frozen section techniques in the treatment of SCC. The formalin‐fixed tissue method has the advantage of providing high‐quality permanent histological sections using existing conventional pathology services.