[Micrographically controlled surgery. Goals and reality]. / Histographische Schnittrandkontrolle. Anspruch und Wirklichkeit.

Micrographic control of surgical margins reduces the risk of recurrence following excision of malignant neoplasms and allows for limited re-excisions of incompletely excised tumors. Several methods for checking surgical margins have been proposed. Principally, transverse sections through the entire specimen must be distinguished from longitudinal sections along all lateral margins. Transverse sections do not demonstrate the entire outer surface of the specimen. This may lead to false-negative results with subsequent recurrences. Longitudinal sections along lateral margins distort the architecture of the neoplasm and may make the diagnosis more difficult. Moreover, extensions of the neoplasm that come very close to lateral margins may be included in those sections, the consequence being false-positive results leading to unnecessary re-excisions. Regardless of the method employed, extensions of the neoplasm are not always recognizable, and, therefore, recurrences cannot be excluded.

Cutaneous mucinosis and skin necrosis complicates interferon alfacon-1 (consensus interferon) treatment of chronic hepatitis C.

A 59-year-old Caucasian suffering from chronic hepatitis C started daily subcutaneous self-injections of interferon alfacon-1 (consensus interferon) according to the protocol of a randomised multicentre study. At week 10, he developed painful erythematous lesions at two injection sites. Consensus interferon dosage was reduced, and eventually, the lesions healed with small areas of scarring due to central necrosis. At week 51, again large areas of erythematous thickened skin arose at two other injection sites followed by substantial ulceration and central necrosis. Skin biopsy revealed excessive dermal mucin deposition so that cutaneous mucinosis was diagnosed. After 3-6 months, the lesions healed with central scarring. Due to a persistently negative HCV-PCR from serum (from week 12 onwards), consensus interferon treatment was not stopped but continued until week 60 according to the study protocol. - Cutaneous mucinosis has not been previously reported to complicate treatment with consensus interferon in patients with chronic hepatitis C and should therefore be added to the list of dermatological side-effects associated with interferon alfacon-1 therapy.

[Pansclerotic porphyria cutanea tarda after chronic exposure to organic solvents]. / Pansklerotische Skleroporphyrie nach langjähriger Exposition gegenüber organischen Lösungsmitteln.

A 63 year old man developed generalized scleroderma with massive sclerotic areas, particularly in the abdominal region, four years after being diagnosed with porphyria cutanea tarda (PCT). He had almost daily exposure to organic solvents (benzene, trichlorethylene) for many years. The cutaneous fibrosis progressed dramatically leading to a pansclerosis, even though the uroporphyrin levels were borderline and the liver enzyme values were normal. Organic solvents are among those substances which can cause a cutaneous fibrosis. The unusually complicated clinical development in our patient was a combination of the two initial factors, the PCT and the long term exposure to organic solvents. The pansclerotic PCT was differentiated from a systemic sclerosis, a disabling pansclerotic morphea and a generalized morphea by means of histological examinations, the absence of a Raynaud phenomenon and the non-involvement of additional organs. Auto-antibodies typical for systemic sclerosis were negative. Using a medium dosage of UVA1 phototherapy and intensive physiotherapy, the progression of the skin disease was stopped and the sclerosis improved.

Case Report. Bullous tinea pedis in an elderly man.

We report a case of recurrent bullous tinea pedis that had been misdiagnosed for a long time and treated with oral steroids. Initially, direct microscopy of potassium hydroxide preparations was negative and culture did not reveal any fungal organism. In a biopsy taken simultaneously from the edge of a bulla and stained with periodic acid-Schiff, septate mycelia were clearly visible. Trichophyton mentagrophytes was later identified in repeated cultures. The infection resulted in two clinical variants of tinea: initially, the vesiculobullous type and later - after intake of steroids because of an unrelated disease - the dry squamous hyperkeratotic type. The change of the clinical pattern indicates the important role of the host's immune response in determining the clinical presentation of the disease.

[Vulvar biopsy as the basis of effective therapy]. / Die Vulvabiopsie als Grundlage einer rationalen Therapie.

Clinical and microbiologic examinations are not always sufficient for a correct and specific diagnosis of diseases of the vulva. In the case of an unusual clinical presentation or an unusual course of the disease, a histopathologic examination is warranted. Importance, technique, and limitations of biopsies of the vulva are illustrated on the basis of three case reports.

[Basic principles of skin biopsy]. / Grundlagen der Hautbiopsie.

Skin biopsies are easy to perform, can be done under direct visual control, allow precise clinico-pathological correlation, and, accordingly, the significance of skin biopsies is very high. This review discusses the basic principles of the interpretation of skin biopsies and alerts to problems that may result from the absence of representative changes of a pathological process in the tissue sections, poor processing of tissue, incorrect assessment of histopathology findings, and shortcomings in the clinico-histopathological correlation.

Fibrous spindle cell lipoma: report of a new variant.

Spindle cell lipoma is a benign tumor characterized by mature fatty tissue alternating with short fascicles of small spindle cells in a stroma that varies from fibrous to myxoid. The variable proportion of these elements among different examples of the neoplasm confers to spindle cell lipoma a variable microscopic appearance that can make the diagnosis difficult. Furthermore, in some instances, spindle cell lipoma may resemble liposarcoma, hemangiopericytoma, neurilemmoma, and other neoplasms representing a histopathologic pitfall. We report on two cases of spindle cell lipoma with abundant fibrous stroma reminiscence of fibroma and fibrolipoma. The name fibrous spindle lipoma is proposed for this tumor.

"Tubular Spitz's nevus" an artifact of fixation?

BACKGROUND: Spitz's nevi may contain numerous tubule-like structures. This phenomenon has been described as "tubular Spitz's nevus" and has been attributed to either apoptosis in the center of nests of melanocytes or tubular metaplasia of melanocytes. METHODS: In order to study this peculiar phenomenon, we reviewed 31 Spitz's nevi from our teaching collection. RESULTS: Empty spaces vaguely resembling tubules were found in 15 Spitz's nevi, all of which were examples of the epithelioid-cell type of Spitz's nevus. Histopathologically and immunohistochemically, there was no evidence of apoptosis within or around tubule-like structures. Empty; spaces in the center of nests ranged from distinctive tubule-like structures to only slight separation of melanocytes from one another. Furthermore, empty spaces were also seen around nests, often in combination with distinctive tubule-like changes. CONCLUSIONS: Our findings suggest that so-called "tubular" structures in epithelioid Spitz's nevi result from retraction of tissue secondary to fixation in formalin. "Tubular Spitz's nevus" seems to represent an artifact rather than a distinctive variant of Spitz's nevus.

Desmoplastic leiomyosarcoma of the skin.

This report focuses on two unusual cases of cutaneous leiomyosarcoma composed of sparse numbers of neoplastic cells embedded in abundant sclerotic stroma throughout the entire neoplasm. To the best of our knowledge, only one example of this rare lesion has been described previously as "sclerotic primary cutaneous leiomyosarcoma." However, the resemblance of this tumor to other desmoplastic tumors of the skin is striking and, therefore, we propose the term desmoplastic leiomyosarcoma of the skin for this neoplasm. Because of the sparse cellularity and the abundant stroma, desmoplastic leiomyosarcoma of the skin can be easily misinterpreted, especially in small biopsies. It should be included in the differential diagnosis of inflammatory skin diseases associated with sclerosis, such as radiation dermatitis, and of desmoplastic tumors of the skin, including desmoplastic melanocytic nevus, desmoplastic melanoma, and desmoplastic squamous cell carcinoma.

Angiomatoid Spitz nevus: a distinct variant of desmoplastic Spitz nevus with prominent vasculature.

Five cases of a distinctive variant of desmoplastic Spitz nevus are reported. To the best of our knowledge, this tumor has never been described previously. Clinically, it presents itself as a solitary papule on the extremities of young adults. Microscopically, it shows predominance of solitary melanocytes with epithelioid appearance over cell nests. They are embedded in a prominent fibrous stroma with many densely arranged, small blood vessels with plump endothelia not seen in other Spitz nevi. Because of its resemblance to a vascular tumor, the name angiomatoid Spitz nevus is proposed for this lesion. Absence of recurrences or metastases after complete excision in all cases supports the benign nature of the tumor.

Panniculitis: definition of terms and diagnostic strategy.

Inflammation of the subcutaneous tissue represents a dynamic process that shows different histopathologic findings at different stages of development; therefore, the stage of evolution of a lesion at the time of biopsy influences the microscopic appearance significantly. Furthermore, location and type of inflammation may vary among different examples of the same panniculitis independent of the stage of evolution. For these reasons, the histopathologic diagnosis of panniculitides is often difficult. Currently, the most common approach to diagnosis is differentiation between predominantly septal and predominantly lobular panniculitis, followed by the distinction between lesions with and without vasculitis. Although these criteria are important for diagnosis, they are often insufficiently specific. To determine an alternative method of diagnosis, 329 cases of panniculitis were histopathologically analyzed using the following parameters: location and type of inflammatory infiltrate within and around the subcutaneous tissue, presence or absence of fat necrosis, type of necrosis, presence or absence of vascular changes, and presence or absence of associated findings (e.g., hemorrhage, sclerosis). On the basis of the results of this study and of an extensive review of the literature, tables of histopathologic findings for the diagnosis of panniculitides are presented.

Benign lymphangiomatous papules of the skin following radiotherapy: a report of five new cases and review of the literature.

AIMS: The aim of this report is to summarize the clinicopathological findings of five cases of a pseudosarcomatous vascular proliferation of the skin at the site of radiotherapy following surgery for carcinoma of the breast and carcinoma of the endometrium. To our knowledge, only five cases of this presumably rare pseudomalignant proliferation have been reported previously. METHODS AND RESULTS: All patients were females ranging in age from 44 to 70 years. The lesions appeared as solitary or multiple papules or vesicles localized to the field of radiation. Microscopically, they were composed of vascular spaces that exhibited atypical features without qualifying for a diagnosis of angiosarcoma. CONCLUSIONS: Our cases provide additional evidence supporting the benign nature of this atypical vascular proliferation, not recurring, never developing metastases and being cured readily by local excision. Clinical, histopathological and ultrastructural findings suggest a lymphatic origin. Whether these lesions represent a neoplastic or a reactive condition secondary to radiotherapy is unclear. The name 'benign lymphangiomatous papules of the skin following radiotherapy' is proposed.

Classification of cutaneous malignant melanoma: a reassessment of histopathologic criteria for the distinction of different types.

BACKGROUND: Human cutaneous malignant melanoma currently is classified into four principle types: nodular, superficial spreading, lentigo maligna, and acral lentiginous. The criteria for the histopathologic diagnosis of these types are not applied consistently. Nevertheless, the classification has become the foundation of many clinical, histopathologic, epidemiologic, and molecular studies. The results of those studies can have validity only if the classification itself is valid. For this reason, the authors reassessed histopathologic criteria advocated for the distinction of the different types of melanoma and searched for other repeatable constellations of findings that may serve to define distinct subsets of the neoplasm. METHODS: Nine hundred fifteen melanomas were examined with regard to 72 parameters that are considered to be important for histopathologic diagnosis. The results were analyzed statistically with special attention to findings that have been reported to be characteristic of the four principle types of melanoma. RESULTS: The histopathologic criteria advocated for the distinction of different types of melanoma were found not to correlate with one another. A logistic regression analysis did not detect any other repeatable constellation of morphologic findings that may reflect a distinct biologic subgroup. CONCLUSIONS: The validity of the current classification of cutaneous malignant melanoma into four principle types could not be substantiated. Malignant melanoma may present with many different forms, but these forms appear to be part of a continuous spectrum rather than examples of distinct biologic entities.