Childhood Soft Tissue Sarcoma Treatment (PDQ®): Treatment - Health Professional Information [NCI] - Treatment of Newly Diagnosed Childhood Soft Tissue Sarcoma
Multiagent chemotherapy may decrease the likelihood of lung metastases: OS at 10 years was 67%, compared with approximately 20% in an earlier series of young patients.
Extraskeletal osteosarcoma is extremely rare in the pediatric and adolescent age range. A 2003 review identified only ten case reports in the medical literature.
Extraskeletal osteosarcoma is associated with a high risk of local recurrence and pulmonary metastasis.
The primary therapy for extraskeletal osteosarcoma is surgical resection of the primary tumor. Chemotherapy for extraskeletal osteosarcoma has not been well studied. It has been recommended that the treatment for extraskeletal osteosarcoma abide by the soft tissue sarcoma (STS) guidelines, rather than the guidelines for osteosarcoma of bone. A report of a series of adult patients with extraskeletal osteosarcoma suggested that adjuvant chemotherapy reduced the risk of recurrence. Extraskeletal osteosarcoma may be more chemosensitive in young patients than in adults. A retrospective analysis of the German Cooperative Osteosarcoma Study identified a favorable outcome for extraskeletal osteosarcoma treated with surgery and conventional osteosarcoma chemotherapy. (Refer to the PDQ summary on Osteosarcoma and Malignant Fibrous Histiocytoma of Bone Treatment for more information.)
Fibroblastic/myofibroblastic tumors include the following tumor subtypes:
- Desmoid tumor.a
- Infant fibrosarcoma.
- Adult-type fibrosarcoma.
- Inflammatory myofibroblastic tumor.a
- Low-grade fibromyxoid sarcoma.
- Sclerosing epithelioid fibrosarcoma.
a Not a high-grade tumor.
Desmoid tumors are also known as aggressive fibromatoses.
Desmoid tumors are low-grade malignancies with extremely low potential to metastasize. The tumors are locally infiltrating, and surgical control can be difficult because of the need to preserve normal structures. These tumors also have a high potential for local recurrence. Desmoid tumors have a highly variable natural history, including well documented examples of spontaneous regression. Mutations in exon 3 of the beta-catenin gene are seen in over 80% of desmoid tumors and the mutation 45F has been associated with an increased risk of disease recurrence. Repeated surgical resection can sometimes bring recurrent lesions under control.
A small number of desmoid tumors may occur in association with a mutation in the adenomatous polyposis coli (APC) gene (associated with intestinal polyps and a high incidence of colon cancer). In a study of 519 patients older than 10 years with a diagnosis of desmoid-type fibromatosis, 39 (7.5%) were found to have familial adenomatous polyposis (FAP) (a possible underestimation). The patients with FAP and desmoid tumors were younger, more often male, and had more abdominal wall or mesenteric tumors than did patients with desmoid tumors without FAP. A family history of colon cancer or the presence of congenital hyperplasia of the retinal pigment epithelium [16,17] or location of the desmoid tumor in the abdomen or abdominal wall  should prompt referral to a genetic counselor.