Soft tissue sarcomas apparently arising in chronic tropical ulcers

Primary cutaneous extraskeletal osteosarcoma: a series of 16 cases

Extraskeletal osteosarcoma (EOS) is a high grade soft tissue tumour characterised by the production of malignant osteoid, without attachment/involvement of underlying bone/periosteum. Rarely, EOS presents as a cutaneous tumour. The clinical behaviour of primary cutaneous EOS (PC-EOS) remains incompletely characterised. Herein we present the largest case series of PC-EOS reported to date. Sixteen PC-EOS cases from the archives/consultation files were retrieved (male:female 1:1; age 31-96 years, mean age 66 years). The tumours measured 1-10 cm (mean 3.2 cm) and were located on the lower extremity (7), head (6), upper extremity (2), and trunk (1). They consisted of pleomorphic, spindled-to-epithelioid cells, with fascicular, nodular, or sheet-like growth patterns and foci of malignant osteoid. Immunohistochemistry did not reveal specific lines of differentiation, and there was no evidence of other tumour types. A literature review was conducted to identify all well characterised cases of PC-EOS. A combined analysis of present and past cases was performed to determine overall trends in clinical characteristics and outcomes. The mean follow-up period was 23.9 months, during which 67.5% of patients experienced progression-free survival and 18% of patients died of disease. Rates of local recurrence and metastasis were 10% and 25%, respectively, approximately double past estimates. These data suggest that the prognosis of PC-EOS is less favourable than previously thought. The differential diagnosis includes benign entities (e.g., ossifying pyogenic granuloma) and malignant neoplasms with heterologous osteosarcomatous differentiation (e.g., carcinosarcoma, transdifferentiated melanoma). Wide excision remains the standard of care, and the role of chemotherapy and radiation remains inconclusive. Recognition of this rare entity can facilitate prompt diagnosis and appropriate treatment.

Primary cutaneous extraskeletal osteosarcoma of the pretibial leg: A case report and summary of the literature

Primary cutaneous extraskeletal osteosarcoma is a rare tumor, with fewer than thirty known cases worldwide. We report the case of a 60-year-old female who presented with a solitary 3 mm right pretibial nodule. She had no known comorbidities, trauma to the area, nor prior malignancy. The biopsy specimen showed abundant mineralized osteoid, in which pleomorphic and spindled cells with anaplastic features were embedded. The osteoid matrix in this case contained overtly malignant cells, with frequent mitotic figures, as well as multinucleated giant cells. Immunohistochemistry and imaging led to the conclusion that this nodule represented a primary cutaneous extraskeletal osteosarcoma. The previously reported cases are variable in location, size, gross appearance, and clinical course. The prognosis of osteosarcoma is typically poor, with aggressive behavior; this, however, may be less severe in these strictly cutaneous tumors, though additional follow-up would be beneficial to determine long-term outcomes for the known cases. Ultimately, despite the fact that this is an extremely rare entity, primary cutaneous extraskeletal osteosarcomas should be considered when relevant. This article is protected by copyright. All rights reserved.

[Extraskeletal osteosarcoma: nosologocal diversity, morphology, differential diagnosis, and features of metastasis]

Extraskeletal osteosarcoma is a rare malignant tumor with histologic similarities to primary bone osteosarcoma. However, there are distinct differences in epidemiology, imaging features, biological characteristics, prognosis, and management compared with osteogenic osteosarcoma. Extraskeletal osteosarcoma is usually characterized as high-grade neoplasm with clinically aggressive behavior, poor prognosis, frequent recurrence/lymphogenic metastatsis, and resistence to chemotherapy. A noteworthy feature of extraskeletal osteosarcoma is the fact that almost all existing biological phenomena described in mesenchymal oncopathology (except primary-multiple lesions) are present in this tumor, namely: secondary malignancy, association with syndromes, partial spontaneous regression of the tumor, dedifferentiation, bone invasion, biphasic pathology. In this paper, we have discussed in detail the tumor morphology, histological subtypes, prognostic factors and differential diagnosis.

Soft-Tissue Sarcomas of the Abdomen and Pelvis: Radiologic-Pathologic Features, Part 2-Uncommon Sarcomas

Soft-tissue sarcomas occurring in the abdomen and pelvis are an uncommon but important group of malignancies. Recent changes to the World Health Organization classification of soft-tissue tumors include the movement of gastrointestinal stromal tumors (GISTs) into the soft-tissue tumor classification. GIST is the most common intraperitoneal sarcoma. Liposarcoma is the most common retroperitoneal sarcoma, and leiomyosarcoma is the second most common. GIST, liposarcoma, and leiomyosarcoma account for the majority of sarcomas encountered in the abdomen and pelvis and are discussed in part 1 of this article. Undifferentiated pleomorphic sarcoma (previously called malignant fibrous histiocytoma), dermatofibrosarcoma protuberans, solitary fibrous tumor, malignant peripheral nerve sheath tumor, rhabdomyosarcoma, extraskeletal chondro-osseous sarcomas, vascular sarcomas, and sarcomas of uncertain differentiation uncommonly arise in the abdomen and pelvis and the abdominal wall. Although these lesions are rare sarcomas and their imaging features overlap, familiarity with the locations where they occur and their imaging features is important so they can be diagnosed accurately. The anatomic location and clinical history are important factors in the differential diagnosis of these lesions because metastasis, more-common sarcomas, borderline fibroblastic proliferations (such as desmoid tumors), and endometriosis have imaging findings that overlap with those of these uncommon sarcomas. In this article, the clinical, pathologic, and imaging findings of uncommon soft-tissue sarcomas of the abdomen and pelvis and the abdominal wall are reviewed, with an emphasis on their differential diagnosis.

Cutaneous osteosarcoma arising from a burn scar

Tumors that develop in old burn scars are usually squamous cell carcinomas. Sarcomas have also been reported, albeit rarely. To our knowledge, there has been only one case report of an extraskeletal osteosarcoma arising in a prior burn scar reported in the English-language literature, mainly discussing the clinicopathological features. Herein, we present a case of cutaneous osteosarcoma visualized as a mineralized soft-tissue mass arising from the scar associated with a previous skin burn over the back. This seems to be the first report describing the imaging features of a cutaneous osteosarcoma from an old burn scar.

Origins of injection-site sarcomas in cats: the possible role of chronic inflammation-a review

The etiology of feline injection-site sarcomas remains obscure. Sarcomas and other tumors are known to be associated with viral infections in humans and other animals, including cats. However, the available evidence suggests that this is not the case with feline injection-site sarcomas. These tumors have more in common with sarcomas noted in experimental studies with laboratory animals where foreign materials such as glass, plastics, and metal are the causal agent. Tumors arising with these agents are associated with chronic inflammation at the injection or implantation sites. Similar tumors have been observed, albeit infrequently, at microchip implantation sites, and these also are associated with chronic inflammation. It is suggested that injection-site sarcomas in cats may arise at the administration site as a result of chronic inflammation, possibly provoked by adjuvant materials, with subsequent DNA damage, cellular transformation, and clonal expansion. However, more fundamental research is required to elucidate the mechanisms involved.

Extraskeletal cutaneous chondroblastic osteosarcoma: a case report

Extraskeletal osteosarcoma is an uncommon neoplasm that usually arises in the deep soft tissues, especially in the lower extremities, with rare cases involving the subcutis or dermis. We report a 60-year-old man with an enlarging cutaneous mass in the right lower thigh. An incisional skin biopsy showed a well-defined, but non-encapsulated neoplasm, characterized by extensive cartilage with marked cellularity, atypia and high mitotic activity, involving the dermis and subcutis. Although osteoid or bone was not observed, a diagnosis of cutaneous chondroblastic osteosarcoma was suggested after excluding an origin in bone or other primary tumor sites by imaging techniques. Histopathologic features of the surgical specimen were characteristic, with a predominant high-grade chondroid component together with focal fibrosarcomatous zones, areas of multinucleated giant cells and foci of bone and osteoid formation. The patient underwent postoperative chemotherapy and is currently alive with pulmonary metastases 15 months after surgery. In summary, we report a unique case of cutaneous osteosarcoma of the chondroblastic subtype, diagnosed on incisional skin biopsy despite the absence of osteoid or bone during tumor sampling. As a rule, when an obviously malignant 'chondrosarcoma' is identified, one should always consider this entity.

Mediastinal malignant fibrous histiocytoma developing from a foreign body granuloma

A patient with mediastinal malignant fibrous histiocytoma (MFH) apparently developing from a foreign body granuloma is reported. A 72-year-old man was admitted to our hospital complaining of generalized fatigue and palpitations. He had undergone surgery for pulmonary tuberculosis 46 years previously. Radiography and computed tomography of the chest showed a round 5-cm mass with marginal calcification in the right side of the anterior mediastinum. The mass was resected completely via median sternotomy. Intraoperative diagnosis of foreign body granuloma was made, based on gauze fragments found in the mass and intraoperative pathologic findings suggesting benign granulation tissue. The postoperative histopathologic diagnosis was myxoid MFH. To our knowledge, mediastinal MFH developing from a foreign body granuloma has not been reported previously.

Primary cutaneous extraskeletal osteosarcoma under a previous electrodessicated actinic keratosis

Extraskeletal osteosarcoma represents approximately 1% of soft tissue sarcomas and approximately 4% of all osteosarcomas. It is therefore much rarer than osteosarcoma arising primarily in bone. Skin as a primary site has seldom been reported. This report describes an extraskeletal osteosarcoma of the skin under a previously electrodessicated actinic keratosis.

Primary metaplastic carcinoma (carcinosarcoma) of the skin. A clinicopathologic study of four cases and review of the literature

Metaplastic carcinoma (carcinosarcoma, sarcomatoid carcinoma, malignant mixed tumor) is a biphasic tumor comprising malignant epithelial and heterologous mesenchymal elements. Primary cutaneous cases are rare, with only seven cases documented in the English literature to date. We present four further cases, including three that developed in association with squamous cell carcinoma and one in an eccrine porocarcinoma. Heterologous malignant mesenchymal elements included malignant osteosarcoma, chondrosarcoma, leiomyosarcoma, and rhabdomyosarcomas. In contrast to metaplastic carcinomas arising in visceral sites, those primarily arising in the skin do not appear to behave in a very aggressive manner (Recurrence rate 22%, metastasis rate 22%, overall mortality 11%). However, the numbers involved are small and the follow-up period is short. In view of recent developments and progress in our understanding of the possible histogenesis of such tumors, we suggest that metaplastic carcinoma rather than carcinosarcoma is the most appropriate term with which to describe these very rare cutaneous neoplasms.

Long-term risk of sarcoma following radiation treatment for breast cancer

Between 1954 and 1983, 7620 patients were treated for breast carcinoma at Institut Gustave Roussy (France). Of these patients, 6919 were followed for at least 1 year. Out of these, 11 presented with sarcomas thought to be induced by irradiation, 2 of which were Steward-Treves Syndrome, and 9 of which were sarcomas within the irradiated fields. All histological slides were reviewed and a comparison with those of breast cancer was done. The sites of these sarcomas were: parietal wall, 1 case; second costal cartilage, 1 case; infraclavicular region, 1 case; supraclavicular region, 2 cases; internal third of the clavicle, 2 cases; axillary region 2 cases; and the internal side of the upper arm (Stewart-Treves syndrome), 2 cases. The median age of these 11 patients at the diagnosis of sarcomas was 65.8 (49-83). The mean latent period was 9.5 years (4-24). Three patients underwent radical mastectomy and nine modified radical mastectomy. Only one patient received chemotherapy. The radiation doses received at the site of the sarcoma were 45 Gy/18 fr. for 10 cases and 90-100 Gy for 1 case (due to overlapping between two fields). The histology was as follows: malignant fibrous histiocytoma, 5 cases; fibrosarcoma, 3 cases; lymphangiosarcoma, 2 cases; and osteochondrosarcoma, 1 case. The median survival following diagnosis of sarcoma was 2.4 years (4 months-9 years). Two patients are still alive: one with recurrence of her breast cancer, the other in complete remission, with 7 and 3 years follow-up, respectively. All other patients died from their sarcomas. The cumulative incidence of sarcoma following irradiation of breast cancer was 0.2% (0.09-0.47) at 10 years. The standardized incidence ratio (SIR) of sarcoma (observed n# of cases (Obs)/expected n# of cases (Exp) computed from the Danish Cancer Registry for the same period) was 1.81 (CI 0.91-3.23). This is significantly higher than one, with a p = 0.03 (One Tailed Exact Test). The mean annual excess (Obs-Exp)/100.000 person-years at risk during the same period/(100,000) was 9.92. This study suggests that patients treated by radiation for breast cancer have a risk of subsequent sarcomas that is higher than the general population. However, the benefit from adjuvant radiation therapy in the treatment of breast cancer exceeds the risk of second cancer; therefore, the potential of radiation-induced sarcomas should not be a factor in the selection of treatment for patients with breast cancer.