Ossifying dermatofibroma with osteoclast-like giant cells

Cutaneous Fibrous Histiocytomas, Ossifying-Variant with Osteoclast-like Giant Cells and Granular Cell-Variant: A Series of Two Unusual Cases with Emphasis on the Differential Diagnosis

The ossifying variant and the granular cell variant are rare subtypes of cutaneous fibrous histiocytoma (CFH), characterized by islands of mature metaplastic bone tissue rimmed by multinucleated osteoclast-like giant cells and by large-sized cells with granular cytoplasm and mildly hyperchromatic nuclei with inconspicuous nucleoli, respectively. We herein present two cases of these unusual CFH variants in a 37-year-old woman and in a 38-year-old man, respectively. The main differential diagnoses, including both benign and malignant lesions, are also discussed.

Cutaneous Bone Formation Associated With Melanocytic Nevus

AIM

Cutaneous bone formation is an uncommon lesion of the skin. It may be primary or secondary. Secondary lesions are mostly associated with melanocytic nevi. Although many different theories have been proposed to explain the etiology, extraskeletal bone formation is complex and poorly understood phenomenon.Here the authors report a series of melanocytic nevi with cutaneous bone formation and the authors described morphologic and clinicopathologic features such as age, sex, location, focus number and size of the lesion.

MATERIAL AND METHOD

Through a single center, this retrospective study presents total number of 20 patients with melanocytic nevus with or without osseous metaplasia. Histologic and clinicopathologic features such as age, sex, location, focus, and size of lesion were compared.

RESULTS

Lesions were identified in 10 female patients. All of the cases were seen in the head and neck region such as face, forehead, eyebrow, lip, and neck and most of them were solitary. The nevi were usually associated with the single focus of ossification. Most of patients (50%) had acne symptoms and treatment anamnesis. Granulomatous dermal inflammation was seen in 2 patients. There was no difference in nevus morphology and the size of the nevi between the osteonevi and the other types of nevi.

CONCLUSION

In conclusion, this study revealed that although it is rare it has distinctive features such as female patients, face location, and acne anamnesis. Therefore it may be speculated that the osteogenic factors may be involved with inflammatory-induced metaplastic ossification and tend to be related female sex.

Dermatofibroma—A Critical Evaluation

Dermatofibromas are common cutaneous lesions. In most cases, they can be readily identified clinically and show a typical histology. In a small percentage of cases they show unusual clinical and more often histologic features that may cause differential diagnostic problems. In addition there are reactive fibrous lesions with neural or smooth muscle features that we speculate may represent dermatofibroma variants.

Cutaneous deposits

: The cutaneous deposition disorders are a group of unrelated conditions characterized by the accumulation of either endogenous or exogenous substances within the skin. These cutaneous deposits are substances that are not normal constituents of the skin and are laid down usually in the dermis, but also in the subcutis, in a variety of different circumstances. There are 5 broad categories of cutaneous deposits. The first group includes calcium salts, bone, and cartilage. The second category includes the hyaline deposits that may be seen in the dermis in several metabolic disorders, such as amyloidosis, gout, porphyria, and lipoid proteinosis. The third category includes various pigments, heavy metals, and complex drug pigments. The fourth category, cutaneous implants, includes substances that are inserted into the skin for cosmetic purposes. The fifth category includes miscellaneous substances, such as oxalate crystals and fiberglass. In this article, the authors review the clinicopathologic characteristics of cutaneous deposition diseases, classify the different types of cutaneous deposits, and identify all the histopathologic features that may assist in diagnosing the origin of a cutaneous deposit.

A clinical and histopathological study of 122 cases of dermatofibroma (benign fibrous histiocytoma)

BACKGROUND

Many variants of dermatofibromas have been described, and being aware of the variants of dermatofibromas is important to avoid misdiagnosis.

OBJECTIVE

We wanted to evaluate the clinical and pathologic characteristics of 122 cases of dermatofibromas.

METHODS

We retrospectively reviewed the medical records and 122 biopsy specimens of 92 patients who were diagnosed with dermatofibroma in the Department of Dermatology at Eulji Hospital of Eulji University between January 2000 and March 2010.

RESULTS

Nearly 80% of the cases occurred between the ages of 20 and 49 years, with an overall predominance of females. Over 70% of the lesions were found on the extremities. The most common histologic variant was a fibrocollagenous dermatofibroma (40.1%). Other variants included histiocytic (13.1%), cellular (11.5%), aneurysmal (7.4%), angiomatous (6.5%), sclerotic (6.5%), monster (4.9%), palisading (1.6%) and keloidal dermatofibromas (0.8%). There were 9 dermatofibromas (7.3%) that were the mixed type with two co-dominant histologic features.

CONCLUSION

The results of this study are consistent with previous reports on the clinical features of dermatofibromas. However, we observed several characteristic subtypes of dermatofibroma and we compared the frequency of the histologic subtypes.

Benign fibrous histiocytoma with osteoclast-like giant cells in an infant

Benign fibrous histiocytoma is a common soft tissue tumor that usually occurs in adults and is relatively rare in childhood. This report describes a 7-month-old Caucasian boy with an enlarging firm congenital nodule on his occipital scalp. Histologic analysis revealed a benign fibrous histiocytoma with osteoclast-like giant cells. Benign fibrous histiocytoma with osteoclast-like giant cells is a rare histologic variant.

Cutaneous Balloon Cell Dermatofibroma (Fibrous Histiocytoma)

Dermatofibroma (DF) or cutaneous fibrous histiocytoma is a common benign skin tumor that exhibits multiple, distinct histologic variants. Although clear cell DF has been described in the literature, balloon cell degeneration causing a clear cell DF phenotype has been not been reported to date. Herein, we describe the clinicopathologic findings of balloon cell DF arising on the heel of a 43-year-old man. Clinically, it presented as enlarging tan-white, ulcerated, firm 1.5 cm nodule, clinically suspected to be pyogenic granuloma. Excisional biopsy revealed a circumscribed fibrous tumor populated by mostly clear and spindle cells. A zonal arrangement separated the varied tumor cells where the most superficial, polypoid area showed large, clear polygonal balloon cells; the mid-dermal zone demonstrated a transition between balloon cells, epithelioid cells, and spindle cells; and the deep dermal zone had storiform arrangement of spindle cells, with the fascicles separated by coarse collagen bundles. A CD10+ > CD68+ > Factor XIIIa+ immunophenotype was identified with negative immunolabeling for S-100 protein, HMB-45, cytokeratin AE1/AE3, desmin, smooth muscle actin, lysozyme, and leukocyte common antigen (LCA). Ultrastructurally, the clear tumor cells were filled with multiple, empty, nonmembrane bound vacuoles of varying size. No recurrence has been described after complete excision and 7 months of follow up. DF with balloon cell change, likely secondary to persistent irritation, should be added to the differential diagnosis of cutaneous primary and metastatic neoplasms showing balloon cell degeneration such as balloon cell melanocytic nevi and renal cell carcinoma, respectively.

Ossifying Adult Xanthogranuloma

Although a xanthogranuloma is a relatively common benign cutaneous condition and ossification has been observed within many cutaneous lesions, the association between ossification and xanthogranuloma has not, to our knowledge, been reported previously. We believe we describe for the first time the case of a xanthogranuloma with marked osseous metaplasia on the trunk of a 41-year-old woman. Microscopically, the lesion showed typical features of a xanthogranuloma, with the exceptional feature of exuberant bone formation. The presence of bone within this lesion is likely secondary to a metaplastic process.

Osteomas of the skin revisited: a clinicopathologic review of 74 cases

Cutaneous ossification is an unusual event that may be primary or secondary to either inflammatory or neoplastic processes. It is classified as primary when it occurs in the absence of a demonstrable preexisting lesion. Secondary lesions have been most commonly reported occurring with pilomatricoma, basal cell carcinoma, acne vulgaris, and melanocytic nevi (nevus of Nanta). Histologically, the osteomas are composed of well-formed bony spicules with prominent cement lines and calcification. They may demonstrate osteoblasts, osteoclasts, and osteocytes and occasionally may even demonstrate bone marrow elements. We searched the files of a reference dermatopathology laboratory to identify cases of either primary or secondary cutaneous ossification. We present a series of 74 cases of primary and secondary cutaneous ossification. Most cases were secondary in nature. Lesions were more common on the head and neck and in whites. Lesions were also more commonly identified in female patients. In addition, included in our series are 19 cases of nevus of Nanta. To our knowledge, this represents the largest series of such cases in the English literature. Cutaneous ossification is seen both in primary and, more commonly, in secondary conditions involving the skin. Benign neoplasms, especially melanocytic nevi, represent the most common cause of secondary osteoma formation. Women are more commonly affected than men, but the reason for this is unclear. The exact reason why osteoma formation occurs is unclear and requires further study.

Metastasizing fibrous histiocytoma of the skin: a clinicopathologic and immunohistochemical analysis of three cases

The clinicopathologic and immunohistochemical features of three metastasizing fibrous histiocytomas of the skin are presented. The first patient had a 1.3-cm nodule in the right thigh, with right inguinal lymph node metastases 19 years later. The second patient, who had a 3-cm nodule excised from his left thigh and inguinal lymph node metastasis after 4 months, had a favorable outcome 14 years after local radiotherapy and chemotherapy. The third had a 2-cm nodule in his neck, which recurred 16 months later. Four months later, cervical lymph node metastases were found. The patient was alive and well 26 months after initial surgery. All three primary skin tumors involved the dermis and subcutis, appeared well-delineated but nonencapsulated, were associated with some degree of epidermal hyperplasia, and showed features of aneurysmal/atypical or cellular fibrous histiocytoma. The number of mitoses ranged from 6 to 11 per 10 high-power fields. Recurrences and metastases showed morphologic features similar to primary lesions. Tumor cells were positive, at least focally, for CD 68, Ki-M1p, and Factor XIIIa, and occasionally for smooth muscle actin. Desmin, CD 34, S-100 protein, and cytokeratin stainings were negative. Primary neoplasms, recurrences, and metastases showed a Mib-1 labeling index of 10% or less. Cellular, aneurysmal, and atypical (pseudosarcomatous) fibrous histiocytomas of the skin can metastasize, yet they often show a protracted clinical course. Risk factors for metastatic dissemination include large size, high cellularity, aneurysmal changes, marked cellular pleomorphism, high mitotic activity, tumor necrosis, and repeated local recurrences.

Primary lung tumors infiltrated by osteoclast-like giant cells

Six primary lung tumors with numerous multinucleated osteoclast-like giant cells (OLGCs) and no osteogenic component were evaluated histologically and immunohistochemically to examine pulmonary lesions inciting an OLGC response. The patients comprised four women and two men ranging in age from 61 to 80 years (average age, 69 years). The tumors consisted of one adenocarcinoma, two sarcomatoid carcinomas, and three giant cell variants of malignant fibrous histiocytoma. One tumor was endobronchial in location, while five were situated peripherally. Tumor diameter spanned from 1 to 6.5 cm (average, 2.7 cm). In addition to the giant cells, common characteristics included the malignant nature of the neoplasms and, in five of six cases, histologically malignant mesenchyme. This array of cases exemplifies the variability of lung lesions which may elicit an OLGC inflammatory response resulting in areas resembling the giant cell variant of malignant fibrous histiocytoma. The results of this study suggest that OLGCs occur preferentially in malignant rather than benign nonosteogenic lung tumors and that sarcomatoid regions of malignant tumors are more likely to be infiltrated by OLGCs than epithelial regions.

Keloidal dermatofibroma: report of 10 cases of a new variant

Dermatofibroma is a common cutaneous tumor. Unusual variants of dermatofibroma that exhibit various epidermal changes or different cellular composition have been described. We observed 10 cases of a novel variant of dermatofibroma characterized by keloidal change within the tumor. Formalin-fixed, paraffin-embedded tissues were used for histochemical and immunohistochemical studies. The patients consisted of six women and four men; median age was 34 years (17 to 59 years). All tumors occurred on the extremities, and six were present for at least 2 years. Tenderness was mentioned in four cases. They were described as erythematous or brown papules 1 cm or smaller. Clinical appearance did not deviate from that of ordinary dermatofibromas. Microscopically, the excised tumors showed a superficial circumscribed area of keloidal change under an atrophic epidermis in an otherwise ordinary dermatofibroma. In the keloidlike area, multinucleated giant cells, hemorrhage, hemosiderin deposits, and scattered KiM1P-positive histiocytes, but not factor XIIIa-positive or CD34-positive cells were present among the thick collagen fibers. There were no known recurrences. This variant dermatofibroma should not be overlooked as a simple keloidal scar. The observation of keloidal change in dermatofibromas may support the connotation that trauma is a possible cause of dermatofibroma. The fact that Asian people are more prone to develop keloid may have led us to find this new variant.