Primary sarcomas of the breast are extremely rare, with less than 0.1% of all malignant tumours of the breast. Mayo Clinic Surgical Pathology database was searched for all breast sarcoma from 1910 to 2000. Pathology reports and slides were reviewed and tumour types were determined. Metaplastic carcinomas and phyllodes tumours were excluded. There were 25 women ranging in age 24 -81 years (mean 45 years). All but one patient presented with a palpable lump. Mastectomy was performed in 19 patients and lumpectomy in five patients. Histopathological diagnoses were fibrosarcoma (six), angiosarcoma (six), pleomorphic sarcoma (six), leiomyosarcoma (two), myxofibrosarcoma (three), hemangiopericytoma (one) and osteosarcoma (one). Tumour size ranged from 0.3 to 12 cm (mean 5.7). Low-grade lesions were observed in 10 cases and high-grade in 15. Overall, mean follow-up was 10.5 years. Local recurrence was observed in 11 patients and ranged from 2 to 36 months (mean 15 m), while distant metastasis was observed in 10 patients (40%) affecting lungs, bones, liver, spleen, and skin. Of the 25 patients, 12 have died of disease and six of other causes. Five-year overall (OS) and cause-specific survival (CSS) were 66 and 70%, respectively. OS and DFS at 5 years were 91% for tumours p5 cm and 50% for tumours 45 cm. Tumour size was significantly associated with OS (risk ratio ¼ 1.3 per 1 cm increase; 95% CI, 1.02 -1.7; P ¼ 0.036). There was no significant difference in OS or CSS between low-and high-grade lesions. In this series, tumour size was a more valuable prognostic factor than tumour grade. Primary sarcomas of the breast are rare, malignant tumours arising from the mesenchymal tissue of the mammary gland (Oberman, 1965;Barnes and Pietruszka, 1977;Callery et al, 1985), with an approximate incidence of 17 new cases per million women (Moore and Kinne, 1996). At the Mayo Clinic, 27 881 malignant breast tumours were seen between 1940 and 1999 (C Adem, personal unpublished data) and 18 breast sarcomas were diagnosed accounting for 0.0006% of breast malignancies.Breast sarcomas should be distinguished from metaplastic carcinomas (Adem et al, 2002). When facing a spindle cell neoplasm in an epithelial organ such as the breast one should be careful in rendering the diagnosis of sarcoma. In this setting, immunohistochemistry using the right antibodies is of major input. Berg et al defined stromal sarcomas of the breast in 1962 as a group of mesenchymal malignant tumours with fibrous, myxoid and adipose components, excluding malignant cystosarcoma phyllodes, lymphomas and angiosarcomas (Berg et al, 1962). However, series in the literature have included many different entities under the rubric of sarcomas such as cystosarcoma phyllodes, lymphosarcoma and carcinosarcoma (Botham et al, 1958;Donegan, 1967;Fawcett, 1967;Kennedy and Biggart, 1967;Rissanen and Holsti, 1968;Gogas et al, 1976;Ludgate et al, 1977;Khanna et al, 1981;Christensen et al, 1988;Terrier et al, 1989;Pitts et al, 1991;Ciatto et al, 1992;Luna Vega et al, 1992;McGregor et al,...

Seven solitary fibrous tumors (SFTs) of the meninges are presented and their clinicopathologic features are compared with those of 64 fibrous meningiomas (FM). Patients with SFT included 5 females and 2 males age 47 to 73 years. The dura-based tumors involved the parasagittal region (1), tentorium (2), cerebellopontine angle (2), and spinal region (2). One each showed invasion of brain and of a spinal nerve root. Of four SFTs with at least 1-year follow-up, one subtotally resected example recurred. No tumors metastasized. All consisted of spindle cells disposed in fascicles between prominent, eosinophilic bands of collagen. Whorls and storiform cell arrangements were lacking. Mitoses ranged from 1 to 7/10 400 x fields. MIB-1 labeling indices ranged from 1% to 18% (mean 4%). All were PAS negative and showed strong immunoreactivity for vimentin and CD34. Of cases studied, half were estrogen and all were progesterone receptor immunopositive. The majority (72%) of FMs occurred in females and most (72%) were supratentorial. Recurrence was noted in 15%. Mitotic activity varied from 0 to 3 mitoses per 10 400 x fields (mean < 1). MIB-1 labeling indices ranged from 1% to 5% (mean 1.5%). Unlike SFT, FMs were glycogen-containing and variously exhibited a storiform pattern (13 of 20), psammoma body formation (9 of 20), and calcification of collagen (4 of 20). Immunoreactivities included vimentin (100%), focal to patchy EMA (80%), S-100 protein (80%), collagen IV (25%), and patchy, mild-to-moderate CD34 staining (60%). Of cases studied, nearly half were estrogen and all were progesterone receptor staining positive. Meningeal SFTs represent a distinct morphologic entity, the morphologic and immunohistochemical features of which differ from those of FM and suggest a histogenetic relationship to pleural SFT. Although a minority histologically appear to be low grade malignant, our limited experience suggests that they behave in a benign fashion. The classification of mesenchymal tumors affecting the central nervous system must be expanded to include SFT.

Twenty-two cases of giant cell tumor of soft tissues (GCT-ST) identified in the Mayo Clinic files and the consultation files of two of the authors (A.G.N., C.D.M.F.) were analyzed clinicopathologically. Age at presentation ranged from 5 to 80 years (median, 43 years), and there was no sex predilection (12 male, 10 female). Duration of symptoms ranged from 2 to 12 months (median, 4.5 months), and a painless growing mass was the most common complaint. The lower limbs were the most frequent location (50%), followed by the trunk (31.8%) and the upper limbs (13.6%). The size of the tumors ranged from 1 to 10 cm, and they tended to be superficial (86.4%), forming well-circumscribed (72.7%), multinodular (86.4%) masses. Histologically, all tumors consisted of a mixture of mononuclear cells showing vesicular, round to oval nuclei and osteoclastlike, multinucleated giant cells distributed uniformly throughout the tumors. Foci of stromal hemorrhage were observed in 11 tumors (50%); nine tumors (40.1%) showed metaplastic bone formation and six (27.2%) showed aneurysmal bone cystlike areas. Necrosis was absent in all but one tumor. Mitotic figures were present in all but one tumor, ranging from two to more than 30 mitoses per 10 high-power fields (HPFs; median, 9.5 mitoses per 10 HPFs) and were typical in aspect. Vascular invasion was identified in seven tumors (31.8%), and none of the tumors showed marked cellular atypia or pleomorphism. The tumors were treated surgically, and follow-up information was available for 16 patients (duration of follow-up, 2 to 130 months; median, 51 months). Only one of the 16 patients (6.2%) had local recurrence and lung metastases; this patient died of the tumor. In conclusion, GCT-ST occurs as a primary soft-tissue neoplasm and is identical clinically and morphologically to giant cell tumor of bone. Provided that GCT-ST is treated adequately by complete excision, a benign clinical course is expected because episodes of distant metastasis and tumor-associated death seem to be exceedingly rare.

Background. Extraskeletal osteosarcomas are rare malignancies that account for about 1% of all soft tissue sarcomas. Few large series have been reported. Methods. Clinical records and histologic slides of all patients with extraskeletal osteosarcomas treated at the Mayo Clinic between 1915 and 1988 were reviewed. Results. The study group consisted of 40 patients, most of whom presented in the sixth and seventh decades of life (mean age, 50.7 years). There was a male predominance (male‐to‐female ratio, 1.9:1). The lower limbs most commonly were involved (68%), usually the thigh and buttock regions. Ninety‐three percent of tumors presented as an enlarging soft tissue mass, with a history of trauma in nine patients. In nine patients, the lesions were initially interpreted histologically as benign, most commonly as myositis ossificans. Histologically, all were high grade osteosarcomas. Multiple local recurrences (45%) are a feature of this tumor. All recurrences occurred within 3 years. Distant metastasis (65%) is also common and is usually to the lungs (81%). Radical resections appear to be the best option for local control, with resection of the pulmonary metastasis occasionally producing a cure. By univariate analysis of Kaplan‐Meier survival curves, the patients with predominantly chondroblastic tumors fared better than those with predominantly osteoblastic tumors (P=0.03). Analysis of survival differences of the three main subtypes together (osteoblastic, chondroblastic, and fibroblastic) was not significant. A small‐sized initial lesion did not equate with better survival. Seventy‐three percent died of the disease, with a mean follow‐up of 5.9 years. Conclusion. Extraskeletal osteosarcoma is a high grade malignant tumor associated with a 5‐year survival rate of 37% (95% confidence interval, 28%–59%). Local recurrences and distant metastasis are common and usually occur by 3 years after excision. Patients with the chondroblastic subtype survive longer than those with the osteoblastic subtype. Cancer 1995; 76:2253–9.