F. Aloi

The clinicopathologic spectrum of rhinophyma

We report the results of a clinicopathologic study of 17 patients with rhinophyma in different stages of evolution, with particular attention paid to the severe form of this disease. On the basis of clinical features, we identified 2 groups of patients: the first group (12/17 patients) included patients with the common form of rhinophyma, whereas the second one (5/17 patients) included patients with the severe form of the disease. There was no link between the clinical aspect and the duration of the disease. Microscopic examination of specimens obtained from the classic type of rhinophyma substantially showed the histopathologic features of fully developed rosacea, except for the presence of prominent sebaceous hyperplasia. The second group showed a very different histologic pattern displaying marked dermal thickness, absence of folliculosebaceous structures, sclerotic collagen bundles with large amounts of mucin, and spreading telangiectasia. The inflammatory infiltrate was inconspicuous, with numerous interstitial spindle and bizarre cells. Most of the interstitial cells were reactive to factor XIIIa. The severe form of rhinophyma shares many histologic characteristics with elephantiasis caused by chronic lymphedema.

Interstitial granulomatous dermatitis with plaques

We report on the clinical and histopathologic findings of four patients who had asymptomatic, erythematous to violaceous plaques symmetrically distributed on the upper aspect of the thighs, lateral chest, and in two cases also on the abdomen and flexor surface of the elbows. All of the patients were women; two of them had arthritis, which in one case was associated with an autoimmune disorder, and another had autoimmune thyroiditis. Histopathologically, all cases showed similar changes consisting of an interstitial granulomatous dermatitis involving mostly the lower reticular dermis. Histiocytes were the predominant cellular component, arranged interstitially and in small palisades around foci of degenerated collagen bundles in concert with large numbers of neutrophils and eosinophils. Interstitial granulomatous dermatitis can present different clinical expressions, including linear cords, papules, and, as in our cases, plaques. This peculiar histopathologic pattern falls into the spectrum of cutaneous extravascular necrotizing granuloma, a condition that is often associated with systemic autoimmune disease.

Basal cell carcinoma with matrical differentiation: matrical carcinoma

Three unusual cases of basal cell carcinoma showing matrical differentiation as evidenced by the focal presence of “shadow cells” within basaloid islands are described. The term basal cell tumor with matrical differentiation seems to be appropriate for this type of tumor. Its differentiation from other tumors, particularly malignant pilomatricoma, is also discussed.

Malignant cellular blue nevus: a clinicopathological study of 6 cases.

BACKGROUND Malignant cellular blue nevus (MCBN) is a rare entity due to the malignant transformation of a preexisting cellular blue nevus (CBN). OBJECTIVE AND METHODS The clinical and pathologic features of 6 patients with MCBN are described. RESULTS Three tumors were located on the scalp, 2 on the trunk and 1 on the neck. The lesions, present from birth or childhood, had enlarged rapidly in the last months before excision. Histologically, there was a dermal proliferation of spindle and epithelioid atypical melanocytic cells. Some of them were heavily pigmented. Numerous atypical mitoses were seen. In 2 cases, foci of necrosis were detected. In 2 cases, remnants of CBN were also noted. MCBN has a poor prognosis and may be difficult to differentiate from so-called atypical blue nevus, metastasis of malignant melanoma and malignant transformation of combined nevus. CONCLUSIONS CBN may represent a precursor of malignant melanoma. In MCBN, malignant changes seem to occur in clear cells.

Agminated Spitz nevi occurring within a congenital speckled lentiginous nevus

A 40-year-old woman had a speckled lentiginous nevus on her thigh since birth. During her first pregnancy, additional papules and nodules appeared within the preexisting hyperpigmented area, histologic examination of which showed features of both junctional and compound Spitzs nevi accompanied by simple lentigolike changes. In this particular case, speckled lentiginous nevus may have constituted a particular environment for the production of multiple Spitz nevi.

Folliculosebaceous cystic hamartoma with perifollicular mucinosis

An 8-year-old boy had a congenital, solitary verrucous lesion on his ear that histologically showed numerous maloriented infundibulocystic structures from which radiated immature sebaceous lobules as well as hair germs with rudimentary papillae. The surrounding stroma was fibrillary, containing large quantities of mucin. We conclude that perifollicular mucinosis, considered to be specific to Carneys syndrome, can also be observed in solitary folliculosebaceous hamartoma.

Immature myeloid precursors in chronic neutrophilic dermatosis associated with myelodysplastic syndrome.

Sweet syndrome (SS) associated with myeloproliferative disorders has been considered an inflammatory process mediated by neutrophils in which immunologic mechanisms are operative. The authors report the case of a 68-year-old man suffering from a myelodysplastic syndrome, who presented with a relapsing skin eruption resembling SS. Histopathologically, the skin infiltrates showed prominent neutrophilic features masking the underlying malignant process. Extensive immunophenotypic studies of skin revealed the presence of a few immature myeloid cells intermingled with an overwhelming infiltrate of neutrophils. The atypical cells in the skin had a phenotype identical to that of leukemic cells in the peripheral blood and bone marrow. Whether or not immature myeloid cell precursors constitute a specific infiltrate of leukemia cutis or are a result of recruitment of circulating leukemic cells to this area of inflammation is discussed.

Mycosis fungoides and Eruptive Epidermoid Cysts: A Unique Response of Follicular and Eccrine Structures

A case of a patient who developed simultaneously mycosis fungoides (MF) and multiple, tiny eruptive cutaneous cysts on the face, neck and upper part of the trunk is reported. Histologically and immunohistochemically MF infiltrate was recognized not only in the upper part of the dermis and in the epidermis but also around and within the walls of cystic lesions. Furthermore, the eccrine structures were also involved by MF infiltrate. We emphasize that MF infiltrate can affect the follicular and eccrine structures inducing the formation of keratinous cysts. The clinical appearance of the facial lesions may be confused with Favre-Racouchot disease.

Nevus comedonicus with Epidermolytic Hyperkeratosis

A 7-year-old girl had a linear nevus comedonicus affecting the right upper limb. Histologic examination of two biopsies specimens showed both the common changes of nevus comedonicus and the presence of epidermolytic hyperkeratosis. Therefore, nevus comedonicus should be included in the list of dermatoses having the distinctive histologic pattern of epidermolytic hyperkeratosis.

Proliferative activity in the malignant cellular blue nevus

The proliferative activity of four malignant cellular blue nevi (MCBN) was assessed in routinely fixed, paraffin-embedded material using staining for the argyrophilic nucleolar organizer regions (AgNORs), immunohistochemical staining for proliferating cell nuclear antigen (PCNA [PC10]), and DNA flow cytometry. The objective was to determine whether the evaluation of proliferative activity could represent a useful diagnostic parameter. Four cellular blue nevi (CBN), 10 melanocytic nevi (MN), four common blue nevi (BN), and 10 conventional malignant melanomas (MMs) were selected as controls. In the MCBN the mean AgNOR number, evaluated on the basis of 100 tumor cells, was 8.33 +/- 0.83; NORs were small and dispersed throughout the nucleus; the mean PCNA score was 31.93% +/- 4.4; and two of the cases were aneuploid and two diploid. In the CBN the AgNOR count was 3.69 +/- 0.56; NORs were large and mainly grouped in a central cluster; the mean PCNA score was 3.53% +/- 1.28; and three of the cases were diploid and one aneuploid. The AgNOR counts in the MCBN were significantly different from those in the CBN (P = .0002), MN (3.04; P = .00001), and BN (2.93; P = .00006), whereas they were not significantly different from those in the conventional MMs (7.64; P = .58). The PCNA (PC10) scores in the MCBN were significantly different from those in the CBN (P = .00003), MN (2.05%; P = .00001), and BN (5.06%; P = .00002), whereas they were not significantly different from those in the conventional MMs (28.9%; P = .49). In all the cases a linear relationship between AgNOR counts and PCNA scores was observed (r = .94, P = .00001). Our results indicate that AgNOR analysis and PCNA immunostaining can be regarded as useful additional parameters for the diagnosis of MCBN.