Extremity rhabdomyosarcoma: biological principles, staging, and treatment

Sentinel lymph node biopsy in head and neck rhabdomyosarcoma

Head and neck rhabdomyosarcoma lymph node staging is challenging due to varied patterns of lymphatic drainage and the suboptimal predictive value of available imaging modalities. Furthermore, regional relapse rates are unacceptably high, and the toxicity of empiric radiation is undesirable in the pediatric and young adult population. In an attempt to improve locoregional control without excess morbidity, we have adopted routine sentinel lymph node biopsy in head and neck rhabdomyosarcoma, which is safe and feasible in pediatric patients. Of six procedures reported here, pathologic findings led to intensification of regional and/or systemic therapy in two patients.

Incidence and outcomes of extremity soft-tissue sarcomas in children

BACKGROUND

We studied the outcomes of pediatric extremity tumors on a population scale.

METHODS

The Surveillance, Epidemiology, and End Results database (1973-2006) was queried for all patients under 20 y of age.

RESULTS

Overall, 1175 patients were identified. The median age at diagnosis was 12 y, but most patients were ≥10 y of age (72%, n = 842). Most tumors were non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) (79%, n = 879). The most common tissue of origin was muscle (43%, n = 474). Most rhabdomyosarcoma (RMS) (n = 220) were alveolar type (n = 140). Most patients presented with local disease (64%, n = 699), and underwent surgical intervention (88%, n = 1027), but did not have radiotherapy (62%, n = 710). RMS was more likely to present in younger children (P < 0.001) and with distant disease (P < 0.001). Older patients were more likely to receive radiotherapy than infants (P < 0.001). Overall 5-y survival was 79%. RMS had significantly worse 5-y survival (56% versus 85% for NRSTS, P < 0.001). Surgical intervention was associated with higher 5-y survival (84% versus 48%, P < 0.001). Radiotherapy was associated with worse 5-y survival (74% versus 83%, P = 0.002). Multivariate analysis identified RMS (HR 2.20, P < 0.001), nerve and muscle (not synovial sarcoma) tissue of origin (HR 2.26, P = 0.002, and HR 1.59, P = 0.036), regional or distant disease (HR 1.65, P = 0.011, and HR 5.96, P < 0.001, respectively), and lack of surgical intervention (HR 2.20, P < 0.001) as independent predictors of poor outcome.

CONCLUSIONS

Extremity sarcomas are most common in older children. RMS is more common in younger children, but is associated with lower survival, and is an independent prognostic indicator of mortality.

Treatment of adult rhabdomyosarcoma

OBJECTIVES

Rhabdomyosarcoma is an exceedingly rare tumor in adults, and standard chemotherapy used for children is much less effective in adults. This study examines short-term outcomes using doxorubicin, ifosfamide, and vincristine for adult rhabdomyosarcoma.

METHODS

Pathology records were searched for adults (age, >18) with rhabdomyosarcoma treated at our musculoskeletal tumor center. Treatment involved surgical resection, radiation therapy, and chemotherapy with doxorubicin, ifosfamide, and vincristine. Eleven met inclusion criteria. Mean age was 49 (range: 19-72). Tumors sites included upper extremity (4 patients), lower extremity (6), and cervix (1). Subtypes were pleomorphic (7), alveolar (1), embryonal (1), and mixed alveolar/embryonal (2).

RESULTS

Of the 7 patients with nonmetastatic disease, 6 had no evidence of disease posttreatment, but 1 died of myelodysplastic syndrome after 51 months. Three patients who received neoadjuvant chemotherapy had 100% tumor necrosis. One patient with positive margins scheduled for adjuvant chemotherapy had local recurrence and metastasis within 2 weeks and died 5 months later. Of the 4 patients with metastatic disease on presentation, 1 had complete response, 2 had partial response with later progression and death at 8 and 24 months, and 1 had immediate progression and died at 12 months. Mean overall survival was 24 months with 6 of 11 (55%) alive at last follow-up. Mean disease-free survival was 17 months for all patients and 23 months for the 7 patients who had remission of all disease.

CONCLUSIONS

When combined with surgery and radiation therapy, chemotherapy using doxorubicin, ifosfamide, and vincristine yielded 55% overall and 64% disease-free survival at 2 years.

Rhabdomyosarcoma of the extremities: a focus on tumors arising in the hand and foot

BACKGROUND

Extremities are peculiar sites of origin for rhabdomyosarcomas (RMS) and are usually associated with an unfavorable outcome.

METHODS

The authors reviewed the clinical data on 60 patients <21 years old with limb RMS treated at the Pediatric Oncology Unit of the Istituto Nazionale Tumori of Milan, in Italy, over a 30-year period. Twelve patients had tumors arising in the hand and foot.

RESULTS

Complete tumor resection was achieved in 21 patients (but in only 1 case of hand/foot RMS); all patients received chemotherapy and 43 also had radiotherapy. The alveolar subtype was identified in 62% of cases. Half of the hand/foot cases had metastatic disease at onset. Overall survival at 5 years was 33% among the hand/foot cases and 56% for the others. Most of the relapsing cases had distant metastases.

CONCLUSIONS

A particularly poor survival was observed for RMS of the hand/foot due its marked tendency to spread. Surgical resection is particularly difficult in such cases and a multimodality treatment approach seems crucial to improving their outcome.

Soft-tissue sarcomas of the extremities in patients of pediatric age

PURPOSE

The extremity site is a peculiar location for soft-tissue sarcomas (STS) of children and adolescents. Here we report the experience of the Pediatric Oncology Unit of the Istituto Nazionale Tumori of Milan, Italy, concerning 204 patients with STS of the limbs treated between 1977 and 2006.

METHODS

The study series included 52 patients with rhabdomyosarcoma (RMS)(65% of which were of the alveolar subtype), nine with extraosseous Ewing sarcoma and 143 with non-rhabdomyosarcoma soft-tissue sarcomas (NRSTS), 38% of which were synovial sarcoma. Patients were treated with a multimodality approach including surgery, chemotherapy, and radiotherapy.

RESULTS

For the RMS patients, the 5-year event-free survival (EFS) rate was 37.1%, with distant metastases being the main cause of treatment failure. The outcome was particularly poor for patients with large invasive tumors, hand/foot involvement and/or nodal or distant metastases, and for patients who were not given radiotherapy. For the extraosseous Ewing sarcoma cases, 5-year EFS was 74%. For the NRSTS cases, the 5-year EFS was 72.6%: tumor size and local invasiveness, tumor grade, malignant peripheral nerve sheath tumor (MPNST) histology, and distant metastases were the main prognostic factors.

DISCUSSION

While the limbs are the most common sites of NRSTS and are often characterized by a more favorable prognosis than for axial tumors, the clinical features of extremity RMS often differ from those of RMS of other sites, with a higher incidence of unfavorable prognostic factors (e.g., alveolar subtype) and consequently unsatisfactory treatment results. The treatment of these patients is complex and necessarily multidisciplinary, and it demands not only adequate experience of treating children and adolescents in clinical trials, but also particular skills in the field of orthopedic surgery.

PET for staging in rhabdomyosarcoma: an evaluation of PET as an adjunct to current staging tools

BACKGROUND

Complete staging of rhabdomyosarcoma is critical to deliver appropriate therapy. We evaluated the role of F-fluorodeoxyglucose positron emission tomography (PET) in the staging of patients with rhabdomyosarcoma.

METHODS

Twenty-four patients with rhabdomyosarcoma had a PET scan during staging evaluation, before or within 13 days of initiation of therapy. PET was compared with computed tomography (CT), magnetic resonance imaging (MRI), bone scan, and pathology.

RESULTS

Ninety-six sites were evaluated. All patients had positive PET scans at the primary site. Thirty-one PET positive sites at primary, regional, or distant sites were biopsied. Pathology in all 31 confirmed disease. Standardized uptake value for the primary site at diagnosis ranged from 2.4 to 12.7 (mean 6.4). At 23 sites, CT or MRI was equivocal for the detection of regional or distant spread. In these cases, a negative PET helped to exclude disease in 21 of 23 patients. PET failed to capture sites of disease visualized by CT, MRI, or bone scan at 10 sites. When comparing PET with the final clinical determination of disease extent, PET was 77% sensitive and 95% specific.

CONCLUSIONS

These preliminary data indicate that PET is a useful adjunct in staging rhabdomyosarcoma. A prospective study of PET for staging of rhabdomyosarcoma is warranted.

Pleomorphic rhabdomyosarcoma in an adult forearm: a case report

Pleomorphic rhabdomyosarcoma (RMS) is a rare malignancy, and treatment protocols for this tumor are not established. Although Intergroup Rhabdomyosarcoma Study data have led to improvement in overall and disease-free survival for children with juvenile RMS, the applicability of those findings to adult pleomorphic RMS is uncertain. This report presents the case of a 29-year-old man with pleomorphic RMS of the forearm (a location not previously reported in current literature); reviews the immunohistochemical, ultrastructural, and histologic diagnostic criteria; and discusses treatment.

Resection of brain metastases from sarcoma

BACKGROUND

Brain metastases from sarcoma are rare, and data concerning the treatment and results of therapy are sparse.

METHODS

We retrospectively reviewed 25 patients with brain metastases from sarcoma of skeletal or soft-tissue origin, surgically treated in a single institution during 20 years.

RESULTS

In 18 patients the brain lesion was located supratentorially, and in 7 patients infratentorially. Median age at brain metastasis diagnosis was 25 years. Median time from primary diagnosis to diagnosis of brain metastasis was 26.7 months. Lung metastases were present in 19 patients and in 8 patients they were synchronous with the brain lesion. Pulmonary metastases were resected in 12 patients (48% of total, and 63% of those with pulmonary lesions). The overall median survival from diagnosis of the primary sarcoma was 38 months and from craniotomy was 7 months. The presence or absence of lung lesions did not alter the median survival as calculated from diagnosis of brain metastasis. Overall percent survival was 40% at 1 year and 16% at 2 years.

CONCLUSIONS

Because brain metastases from sarcoma are refractory to alternative treatment, surgical excision is indicated when feasible. Brain metastases from sarcoma are uncommon, usually occurring with or after lung metastasis. Long-term survival is possible in some patients.