Nobuko Tabata

Dermatofibrosarcoma protuberans is a unique fibrohistiocytic tumour expressing CD34

Summary Dermatofibrosarcoma protuberans (DFSP) is a slow growing, locally invasive tumour whose differentiation from other fibrohistiocytic tumours sometimes poses serious diagnostic problems. We investigated CD34 expression immunohistologically in various fibrohistiocytic tumours including dermatofibroma, DFSP, malignant fibrous histiocytoma (MFH), infantile myofibromatosis, fibrosarcoma, hypertrophic scar and keloid. Among these, DFSP was unique in that tumour cells themselves expressed CD34, whereas in other tumours, CD34 expression was observed only on vascular endothelial cells amongst the tumour cells. Until now, there have been no reports of useful immunohistological markers for DFSP. CD34 expression by the tumour cells can be an extremely useful marker in establishing a definitive diagnosis of DFSP.

Epidemiology and prognosis of subungual melanoma in 34 Japanese patients

The incidence of malignant melanoma is much lower in the Japanese than in Caucasians. However, amongst the various types of malignant melanoma, the subungual and periungual sites are commonly found in the Japanese. One hundred and fifty‐one cases of cutaneous malignant melanoma were seen over a 25‐year period at our hospital. We found that. In 34 patients (23%). the subungual region was involved, a high frequency for one institution. We have analysed these patients and looked at their treatment. The finger nails were affected in 21 cases (62%) and the toe nails in 1 3 cases (38%). The thumb nails or great toe nails were at tecled in 25 of the 34 patients (73%). In 25 patients, histopathological features of acral lentiginous melanoma were found, with four cases of superficial spreading melanoma and five of nodular amelanotic melanoma. Of the latter group, four mimicked tibrous histiocytic tumour, and one was a desmoplastic malignant melanoma. I he proportion of patients presenting with stage III disease decreased after 1982. with a corresponding increase in patients whose tumour thickness was less than 4 mm (stage II). Concurrently, the prognosis for subungual malignant melanoma improved. The 5‐year survival rate in each of the periods 1969–82 and 1981—93 was 5 3 and 87%. respectively. This is similar to that found in plantar malignant melanoma and is fell to be due to a greater public awareness of the condition and to the introduction of effective chemotherapy (the DTIC‐AC nitro surear vincristine (OAV) regimen). Although the frequency of malignant melanoma is rather low in the Japanese, our data indicate that there is a high incidence of subungual malignant melanoma. Public awareness of the early stage of malignant melanoma seems to have improved prognosis.

Biophysical Assessment of Persistent Effects of Moisturizers after Their Daily Applications: Evaluation of Corneotherapy

Background: Although effective moisturizers can improve xerotic skin changes immediately, their effects are only transient, because the materials applied to the stratum corneum (SC) are easily shed from the skin surface by the daily desquamation process. However, there are a few lines of clinical as well as experimental evidence suggesting that, once application of effective moisturizers is repeated daily, they may produce persistent effects without being influenced by the desquamation of the skin surface. If we can expect such pharmacological effects by simple repeated applications of moisturizers on the skin surface, it will provide a great motivation for the introduction of corneotherapy into the treatment of xerotic skin problems. Objective: This study was designed not only to confirm the feasibility of corneotherapy but to propose a practical method to assess such long-lasting effects of moisturizers by using biophysical methods. Methods: We conducted applications of various moisturizers twice daily to different areas of the flexor surface of the forearms for the initial 5 days of the first week. Thereafter, we performed biophysical measurements of the SC of these areas in the second week, namely 3, 5 and 7 days after their last applications. Results: Daily repeated applications of moisturizers did not induce any change in the water barrier function of the SC or in the size of desquamating corneocytes, a parameter for turnover rate of the SC. However, they substantially increased high-frequency conductance, a parameter for the hydration state of the skin surface, for several days in both normal individuals and patients with atopic xerosis, although the lasting effects were shorter in the latter. The obtained data enabled us to rank the efficacy of moisturizers either according to the duration of the lasting effects or the magnitude of an increase in the hydration levels of the SC. Conclusion: The present results confirmed the feasibility of corneotherapy, in which even simple application of moisturizers targeted at the SC can produce unexpected persistent clinical effects after their repeated treatments. The method described in this study constitutes a practical assay system to evaluate the efficacy of topical agents used for dry skin problems objectively and quantitatively.

Dehydroepiandrosterone may be one of the regulators of cytokine production in atopic dermatitis.

Previous studies in mice have shown that dehydroepiandrosterone (DHEA) increases the production of Th1-associated lymphokines, and of interleukin-2 (IL-2) and interferon-gamma (IFN-γ), by lymphocytes. However, there are no reports concerning the effect of DHEA on the production of Th2-associated lymphokines, IL-4 and IL-5, by lymphocytes in humans. We examined serum DHEA levels in patients with atopic dermatitis (AD), which is thought to be associated with a higher activity of Th2 cells than of Th1 cells. We also studied the effects of DHEA on the production of IL-4 and IL-5 by human lymphocytes. Serum DHEA concentrations in 47 adult male patients with AD aged 19–30 years were significantly lower than those of 53 age-matched healthy male controls. Preincubation of peripheral blood mononuclear cells (PBMCs) with DHEA reduced the IL-4 production by concanavalin A-stimulated PBMCs. Their IL-5 production also showed a tendency to decrease. These results suggest that DHEA may be one of the regulators of IgE synthesis and eosinophil proliferation in patients with AD and it may act by controlling IL-4, IL-5 and IL-2 production by lymphocytes.

A twenty-four-hour occlusive exposure to 1% sodium lauryl sulfate induces a unique histopathologic inflammatory response in the xerotic skin of atopic dermatitis patients.

Twenty-four-hour occlusive exposures of 1% aqueous sodium lauryl sulfate (SLS) produced unique functional and histological responses in patients with atopic dermatitis. Disruption of the stratum corneum barrier, measured by transepidermal water loss, was much greater and longer lasting than in normal controls. In contrast to controls the histologic pattern induced reproduced the typical features of the disease with spongiosis, exocytosis of mononuclear cells and a perivenular infiltrate containing eosinophils. The perivascular infiltrate consisted of CD1a+, CD4+ and HLA-DR+ cells, which was much greater and more persistent in atopics. Eosinophilic major basic protein was abundant in atopics but absent in controls. SLS provocation of atopic dermatitis is a striking experimental example of Koebnerization, in which disruption of the stratum corneum barrier as well as cytokine activation of keratinocytes reproduces the clinical diseases.

Hydroa vacciniforme-like lymphomatoid papulosis in a Japanese child: A new subset

An 8-year-old Japanese girl had a 9-month history of a self-healing papulovesicular eruption on her face, scalp, and neck that resembled hydroa vacciniforme (HV). Histologically, there was a dense infiltration of small lymphocytic cells and scattered large atypical cells expressing CD30. Study of gene rearrangement showed no monoclonality in the infiltrating cells. To our knowledge, this is the second case of lymphomatoid papulosis with clinical features resembling HV. However, we also found descriptions in the literature of two other Japanese children with malignant lymphoma who both initially had clinical features resembling HV. These findings suggest that these cases of HV-like disease constitute a subset of lymphomatoid papulosis that is highly likely to progress to malignant lymphoma.

Epidemiology and prognosis of plantar melanoma in 62 Japanese patients over a 28‐year period

Background The plantar surface is one of the commonest sites of malignant melanoma in the Japanese; however, the biological behavior is not sufficiently clarified, because of the paucity of long‐term studies. We attempted an epidemiologic survey of the cases of plantar melanoma treated in our institute to study the survival rate in the recent period.

Non-pigmented nodular plantar melanoma in 12 Japanese patients

In the Japanese, melanoma most commonly involves the plantar surface. Among 61 patients with plantar melanoma, we diagnosed 50 patients as acral lentiginous melanoma (ALM), nine as nodular melanoma, and two as superficial spreading melanoma. Partial or complete loss of pigment was observed in four of the nine nodular melanoma cases and in the nodular portions of eight ALM cases.

A simple method to treat an ingrowing toenail with a shape-memory alloy device.

An ingrowing toenail has no definitive treatment. Previously, effective methods were complicated but easy ones had less effect. We show both an easy and an effective way with Cu‐Al‐Mn‐based shape‐memory alloys (SMAs). They have a characteristic shape which patients themselves can detach easily without any pain. But they also have enough corrective force. Cu‐based SMAs cost much less than Ni‐Ti‐based alloys. Despite not being appropriate for all cases of ingrowing toenails, it is an easy, effective and less costly alternative.

Clinicopathological Study of Acral Melanoma in situ in 44 Japanese Patients

BACKGROUND Acral lentiginous melanoma (ALM) has been a major focus of interest in Japan in the last 2 decades. A remarkable improvement recently made in the prognosis of ALM at our institution may possibly be explained by early detection including melanoma in situ. OBJECTIVE We have retrospectively studied 44 cases of melanoma in situ in the past 25 years from 1970 to 1994, 61% of which have been seen in the last 5 years. RESULTS Of 190 cases of invasive malignant melanoma including 20 melanomas involving the mucous membrane, 96 were ALM. Accordingly, the number of cases of melanoma in situ involving the acral regions was also prominent. Of 44 melanomas in situ, 29 occurred in the acral regions. Eight lesions localized on the face were compatible with lentigo maligna both clinically and histologically. All 6 mucosal lesions occurred on the oral mucosa. The remaining lesion appeared on the back of a psoriatic patient treated with photochemotherapy. Forty-two specimens showed histologically a lentiginous proliferation including atypical solitary cells within the lower portion of the epidermis, especially in the basal layer. The remaining 2 specimens were histologically of the pagetoid type. CONCLUSION Corresponding to the fact that ALM are predominant in the Japanese, the most common sites of melanoma in situ are also the acral regions.