Scott E. Kilpatrick

Mixed tumors and myoepitheliomas of soft tissue : A clinicopathologic study of 19 cases with a unifying concept

We report 19 unusual cases of mixed tumors and myoepitheliomas arising in soft tissues. The neoplasms occurred in 12 males and seven females. The age at diagnosis ranged from 2 to 83 years (mean 35, median 30). Eight tumors arose in the upper limb, six in the lower limb, three in the trunk, and two in the head and neck region. Three cases involved both dermis and subcutis; the remainder arose in subcutaneous (13 cases) or deep subfascial soft tissue (three cases). The most common presenting complaint was a painless swelling, with duration ranging from 2 weeks to 1 year (median 2.5 months). Microscopically, the tumors were predominantly well circumscribed and lobulated. Six cases showed a focally infiltrative margin. Cardinal morphologic features included nests, cords, and ductules of epithelioid cells and/or nests of spindled cells within a hyalinized to chondromyxoid stroma. One tumor was predominantly composed of myoepithelial cells and devoid of epithelial differentiation (i.e., ductules). Cytoplasmic hyaline inclusions were noted in two cases; squamous differentiation was seen in one case. Osteoid production and/or metaplastic bone was observed in three tumors. Chondroid differentiation (usually mature) was seen in four cases. Adipocytic differentiation was seen in two tumors. Mitotic activity was variable but generally scant; atypical mitotic figures were not identified. By immunohistochemistry, 16 of 16 cases expressed pan-keratin; 16 of 17 S-100 protein; six of 14 alpha smooth muscle actin (IA4); two of 10 muscle specific actin (HHF-35); two of 10 desmin; three of 11 glial fibrillary acidic protein; and three of 16 epithelial membrane antigen. Clinical follow-up was available in 10 patients and ranged from 6 months to 20 years (mean 4.25 years, median 2 years). Two patients developed local recurrence; metastasis to lung and lymph nodes were observed in two additional patients. Both of the latter patients died. We believe that these findings expand the concept of cutaneous mixed tumors to include neoplasms composed predominantly of myoepithelial cells and to include tumors arising in deeper subcutaneous and/or subfascial tissues. The clinical behavior of such neoplasms, when arising in soft tissues, may be difficult to predict but is most often benign; however, a minority of lesions metastasize. Until larger studies with longer follow-up are available, treatment and prognostication are probably best based on criteria used in comparable salivary gland tumors.

Fate of liposuctioned and purified autologous fat injections in the canine vocal fold.

Injection of autologous fat obtained by liposuction has been reported as an augmentation technique for vocal fold paralysis. Unfortunately, it is not known whether this technique is associated with long‐term graft survival.

Atypical and malignant variants of ossifying fibromyxoid tumor. Clinicopathologic analysis of six cases.

Ossifying sibromyxoid tumor (OFMT) of soft parts is a recently defined fibro-osseous neoplasm. the biologic behavior of which is generally regarded as benign. We report six variant cases of OFMT with histologic features of malignancy, two of which behaved aggressively. All these tumors arose in the extremities of adults (aged 36–76 years), and five of the six were subcutaneous. Four patients were men. Macroscopically, all the tumors were well circumscribed and somewhat lobulated. Cardinal morphologic features included lobulates of round to spinded cells within a fibromyxoid matrix and randomly distributed, often centrally located osteoid within which were plump neoplastic cells. In contrast to typical OFMT, a hypocellular, cytologically benign, lamellar bony shell was observed only focally: cellularity was increased (four cases), and mitotic activity was frequent, exceeding two mitotic figures per 10 high-power fields (three cases). One case associated with metastases was morphologically bland. Immunohistochemically, positivity for S-100 protein was observed in the primary tumors of three cases and in the pulmonary metastasis of a fourth. Desmin was positive in one case. Ultrastructural features in three cases were very similar to usual OFMT. Clinical follow-up revealed local recurrence in two cases: one patient has developed recurrent pulmonary metastases. We believe these findings support the view that some atypical cases of OFMT exhibit morphologic patterns that might predict more aggressive behavior.

Leiomyoma of deep soft tissue: clinicopathologic analysis of a series

Leiomyomas of deep soft tissue are extremely rare and, to our knowledge, have never been adequately characterized either histologically or clinically. We report 11 such cases, most often arising in deep subcutis or skeletal muscle. The lesions were equally distributed among males (six cases) and females (five cases); age at presentation ranged from 14 to 62 years (mean, 37 years; median, 35 years). The extremities represented the single most common site (five cases). Characteristic morphologic features included well-defined circumscription with a fibrous pseudocapsule, myxohyaline stromal degeneration, and intersecting fascicles of spindle cells with mostly uniform, round-ended, elongated nuclei and tapering, eosinophilic cytoplasm. Dystrophic calcification was identified in four cases; degenerative nuclear changes, similar to those in ancient schwannoma, were present in three cases. Two neoplasms showed multiple necrobiotic granuloma-like nodules resembling giant rosettes. Mitotic figures were found in only four cases and were scarce, never exceeding one mitotic figure per 50 high-power fields. Immunohistochemically, all cases showed desmin positivity. Clinical follow-up (median, 4.5 years), available for nine cases, revealed no evidence of local recurrence or distant metastasis. As with all smooth-muscle cell neoplasms, meticulous attention to the presence of significant mitotic activity and suppurative tumor necrosis is essential because they suggest potential malignant behavior.

Desmoplastic Malignant Melanoma of the Oral Mucosa An Underrecognized Diagnostic Pitfall

Although cutaneous desmoplastic malignant melanoma (DMM) has been well characterized, those arising from the oral mucosa have been less well defined.

Myxoid chondrosarcoma (chordoid sarcoma) of bone

Chondrosarcoma of bone is a well recognized, relatively common clinicopathologic entity. Morphologically distinct soft tissue chordoid sarcoma (CS), or extraskeletal myxoid chondrosarcoma, is a relatively rare tumor that has generally been documented in extraosseous soft tissues.

Histogenetic relations between giant cell fibroblastoma and dermatofibrosarcoma protuberans. CD34 staining showing the spectrum and a simulator.

The authors describe three lesions that provide further evidence for a close, possibly histogenetic relation between giant cell fibroblastoma and dermatofibrosarcoma protuberans. The first case involves a dermatofibrosarcoma protuberans that contained a single giant cell fibroblastoma-like focus of multi-nucleate giant cells. A second tumor, a giant cell fibroblastoma, recurred 6 years later as a dermatofibrosarcoma protuberans. In the third lesion, there was a juxtaposition and co-mingling of dermatofibrosarcoma protuberans and giant cell fibroblastoma within the same primary lesion. In all cases, both the giant cell fibroblastoma areas and dermatofibrosarcoma protuberans areas stained positively with CD34. A fourth case, a dermatofibrosarcoma protuberans infiltrated skeletal muscle, creating giant cell fibroblastoma-like giant cell mimics--a result of skeletal muscle degeneration or atrophy with nuclear conglomeration. The latter giant cells failed to express CD34 but did show immunoreactivity with desmin. These findings support the concept that giant cell fibroblastoma and dermatofibrosarcoma protuberans probably represent a histologic spectrum of a single CD34 positive (perhaps, dermal dendrocytic) neoplasm, a conclusion supported by a recently cloned t(7;22) breakpoint demonstrated in both neoplasms.

Inflammatory Myofibroblastic Tumor With Bone Marrow Involvement A Case Report and Review of the Literature

Inflammatory myofibroblastic tumor, also referred to as inflammatory fibrosarcoma, is a rare tumor composed of myofibroblastic spindle cells of uncertain etiology and disputed nosology. We report a case of inflammatory myofibroblastic tumor of the omentum with involvement of the bone marrow in an 18-year-old man. Histologic and immunohistochemical studies of the abdominal mass and bone marrow were consistent with inflammatory myofibroblastic tumor. Additionally, fluorescence in situ hybridization using a probe specific for the ALK gene showed disruption of the gene. The literature is reviewed with emphasis on the ability of inflammatory myofibroblastic tumor to recur, metastasize, and cause mortality.

Dedifferentiated chondrosarcoma in patients with multiple osteochondromatosis: report of a case and review of the literature

Abstract Multiple osteochondromatosis (MOS) is a familial disorder of autosomal dominant transmission characterized by the development of multiple exostoses and often derangements of epiphyseal cartilage, sometimes resulting in long bone growth retardation. Patients with the disorder appear to be at increased risk for developing secondary chondrosarcomas. Rarely, dedifferentiated chondrosarcomas may also occur. We report a single case of a 27-year-old man with multiple osteochondromatosis who developed a fatal dedifferentiated chondrosarcoma. Radiographically, the neoplasm arose from the pelvis completely destroying the left pubic ramus. Subsequently, the patient underwent preoperative chemotherapy followed by a left external hemipelvectomy. On pathologic examination, the tumor was characterized by high-grade pleomorphic sarcoma sharply juxtaposed to a low-grade chondrosarcoma. The patient ultimately died of widespread metastatic sarcoma.

Fine-Needle Aspiration Biopsy of Sarcomas and Related Tumors

BACKGROUND Largely due to a lack of experience, familiarity, and/or confidence, few centers rely on simple fine-needle aspiration biopsy (FNAB) for the diagnosis of sarcomas and related tumors. METHODS The authors have reviewed their own experience in more than 200 cases of FNAB of bone and soft-tissue tumors, as well as cases reported in the literature. RESULTS FNAB has proven to be accurate and useful in 8 consecutive years of clinical experience. No serious complications have occurred. CONCLUSIONS FNAB is recommended as an integral part of the initial evaluation of amenable orthopaedic tumors, including sarcomas, especially in cases with classic clinical and radiographic findings.