Overview, Papulosquamous Disorders, Erythematous Lesions. Acanthosis nigricans. Acanthosis nigricans (AN) manifests as a hyperpigmented, velvety thickening of the skin that usually occurs in the intertriginous zones, including the axillae, groin, neck, and inframammary folds. AN may develop in areas subjected to trauma, such as the extensor surfaces of the knees and elbows. As many as 3. 0% of patients also have papillomatous thickening of the oral mucosa. Patients who have AN associated with malignancies also have skin changes involving the scalp, areolae, and eyelids. The appearance of paraneoplastic AN usually coincides with the presence of malignancy, but it can precede or follow the diagnosis of cancer and thus may signal a relapse in patients with a history of cancer. Diagnosis. The diagnosis of AN is based on clinical findings alone and can be supported by the histopathologic changes of hyperkeratosis and papillomatosis of the epidermis. Acanthosis is seldom present, and hyperpigmentation is related to hyperkeratosis, not melanin deposition; therefore, the condition is misnamed. Not all patients with AN have a paraneoplastic syndrome. Familial AN, drug- induced AN, AN occurring in hyperinsulinemic states (eg, diabetes, obesity), AN associated with polycystic ovary disease, and AN associated with a spectrum of autoimmune disease in women should be considered before AN is determined to represent a paraneoplastic syndrome. Clinical features suggestive of paraneoplastic AN include the development of AN in nonobese elderly persons and the rapid extensive progression of florid skin lesions in unusual locations, such as the mucosal membranes, palms, and soles of the feet. Other paraneoplastic syndromes that commonly occur with AN include tripe palms and the sign of Leser- Tr. Benign conditions associated with AN involve insulin resistance and hyperinsulinemia, but insulin levels are not elevated in persons with paraneoplastic AN. One well- studied patient with AN had elevated levels of transforming growth factor (TGF). Activation of signaling pathways by binding of growth factors to specific skin receptors could play a primary role in the pathogenesis of paraneoplastic AN, but more study is needed. Treatment. No specific effective therapies are available for AN. Treatment should be directed at the associated underlying condition. Although isolated reports have described combination chemotherapy aiding distressing symptoms associated with paraneoplastic AN. However, complete remission of AN has been reported with tumor regression, while the recurrence of AN has been associated with progression of internal malignancy. Calcipotriene, retinoids, and urea have been used as topical therapy; no single treatment is considered effective. Acquired ichthyosis. Acquired ichthyosis (AI) is extremely rare and is virtually clinically indistinguishable from autosomal dominant ichthyosis vulgaris. The palms and soles are usually spared. This condition is associated with a variety of chronic illnesses, including malignancy. Malignancy- associated AI may occur at any point in the course of the cancer. In the case of Hodgkin disease, AI often precedes the diagnosis of lymphoma and may be the initial manifestation. Diagnosis. The diagnosis of paraneoplastic AI is based on history and clinical findings. An adult onset of ichthyosis is critical in establishing the diagnosis of AI; a family history of scaling and early onset (age 3mo) supports a diagnosis of congenital AI. Skin biopsy findings are not diagnostic, but sometimes they can support the clinical impression. The epidermis has moderate orthohyperkeratosis and parakeratosis. Sometimes, mild acanthosis and thinning of the granular layer are present or the granular layer may be absent. Superficial perivascular lymphohistiocytic infiltrates may be present in the dermis. Patient demographics are not significantly different from those expected with the associated underlying cancer. The cause of AI is not ascertainable by means of clinical examination of the skin alone. As with AN, unless cancer is strongly suggested based on clinical findings, nonmalignant disease associations, which are far more common than malignant associations, should be excluded first. Thus, the diagnosis of paraneoplastic AI becomes a diagnosis of exclusion. The differential diagnosis of AI includes xerosis or asteatotic eczema. Some drugs, including lansoprazole, niacin, retinoids, and the statin class of lipid- lowering drugs, cause clinically significant, generalized xerosis. As a paraneoplastic syndrome, AI is often impossible to distinguish from drug- induced ichthyosis; thus, the patient's history remains critical in the diagnosis. Associated noncancerous conditions. AI is associated with a number of chronic, nonmalignant conditions, including the following. On vous propose de venir vous d Crohn\'s Disease Forum - Support group and forum for Crohn\'s Disease, Ulcerative Colitis, and other IBD. Inlet Knight crew-members Cory and Matt, two of the finest Canadian Pacific Northwest log-towers, enjoying some Jake's Mint Chew while rigging up their gear. Acquired immunodeficiency syndrome (AIDS). Systemic lupus erythematosus. Sarcoidosis. Autoimmune disease - Eg, dermatomyositis and mixed connective- tissue disease. Endocrine abnormalities - Eg, hyperparathyroidism and hypothyroidism. Malnutrition. Infectious etiologies - Eg, tuberculosis and leprosy. Use of certain medications - Eg, nicotinic acid, cimetidine, and clofazimine. Associated cancers. Among malignancies, AI is most strongly associated with Hodgkin lymphoma; as many as 7. AI involve Hodgkin disease. Other AI- associated malignancies include Kaposi sarcoma, cutaneous T- cell lymphoma.
Rare cases of AI associated with graft versus host disease (GVHD) have been reported after allogeneic bone marrow transplantation. Other postulated mechanisms include an autoimmune response directed against the skin (as is seen in GVHD) and the secretion of keratinocyte growth factors by solid tumors (transitional cell carcinoma of the kidney. Treatment. Paraneoplastic AI responds to successful treatment of the underlying malignancy. The mainstay of symptomatic treatment of AI includes hydration of the skin and prevention of evaporation. This is achieved through the topical application of alpha- hydroxy acids (eg, lactic, glycolic, and pyruvic acids) and emollients (eg, urea creams, propylene glycol). Topical corticosteroids are not useful. Acrokeratosis paraneoplastica (Bazex syndrome)In 1. Bazex described the development of eczematous or psoriasiform plaques on acral surfaces in association with an underlying cancer. The clinical features of Bazex syndrome include symmetrical, scaly, violaceous plaques on the acral surfaces, with severe forms progressing to bullae. The lesions predominantly occur on the hands, feet, ear helices, nose tip, and scalp. Skin changes may spread to involve the knees, elbows, and malar surface of the face. Subungual hyperkeratosis, onychodystrophy, and white flaking of the nail surface are the usual manifestations. These changes may progress to the point that the nail sheds. Diagnosis. Histopathologic analysis of samples from the affected sites reveals nonspecific changes, including hyperkeratosis, acanthosis, parakeratosis, and dyskeratotic keratinocytes. Perivascular lymphocytic infiltrates are variably present with eosinophils and neutrophils. Direct immunofluorescence is also nonspecific. The diagnosis is based on the characteristic distribution of skin changes. The main entity in the differential diagnosis is acral psoriasis, with the entire ear typically affected. Acrokeratosis paraneoplastica is almost always noted on the nose tip and ear helices. Clinical course. Skin eruptions often precede detection of the cancer, with a reported median interval of as long as 1 year between the onset of skin changes and the diagnosis of malignancy. The development of the lesions also tends to parallel the course of malignancy; skin manifestations arise in 3 well- characterized stages that parallel the dissemination of the underlying cancer. The lesions may regress with successful cancer therapy and may recur with relapses, thus serving as a marker for status. Acrokeratosis paraneoplastica is often associated with other paraneoplastic syndromes, including dermatomyositis (DM), AN, and the sign of Leser- Tr. Epidemiology and associated cancers. Bazex syndrome appears to be exclusively associated with malignancy; therefore, its presence should prompt an extensive search for an occult cancer. The prevalence appears to be increased in men older than 4. This finding is likely related to the specific cancers that occur with greater frequency in males. Acrokeratosis paraneoplastica is most commonly associated with squamous cell carcinomas of the upper aerodigestive tract, including the tongue, floor of the mouth, palate, tonsils, pyriform sinus, larynx, pharynx, esophagus, and lungs. In 2. 00. 6, an unusual case of Bazex syndrome associated with a liposarcoma was reported, with associated dermatologic findings in parallel with subsequent recurrences of the tumor. Suggested mechanisms include cross- reactivity between the tumor antigens and the basement membrane or epidermal antigens, leading to basement membrane damage. Other possibilities include tumoral production of growth factors (eg, TGF- alpha, insulinlike growth factor), low serum levels of vitamin A, and zinc deficiency. Treatment. In as many as 9. In severe cases, the lesions have regressed after treatment with topical and systemic steroids, oral retinoids, and oral psoralen given together with ultraviolet- A (UV- A) phototherapy. Extramammary Paget disease. Paget disease is characterized by a solitary, pruritic (but painless), sharply demarcated, erythematous, superficial, eczematous, slightly infiltrated plaque, which usually appears on the areola. The lesion of extramammary Paget disease (EMPD) is clinically indistinguishable from that of Paget disease, except for its location; lesions in persons with EMPD typically appear on the apocrine gland. Occasionally, cases involving the face. These lesions either may coexist with the classic erythematous lesions or may be the only presenting sign of EMPD. EMPD is more common in women (1.
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