Characteristics and outcomes of rhabdomyosarcoma patients with isolated lung metastases from IRS-IV.
OBJECTIVE
To better understand outcomes in children with rhabdomyosarcoma (RMS) and lung-only metastatic disease, the authors reviewed the experience from Intergroup Rhabdomyosarcoma Studies IV Pilot and IV.


METHODS
Patients with lung-only (n = 46) vs other sites of metastatic disease (n = 234) were reviewed using patient charts and the database of Children's Oncology Group (COG).


RESULTS
Sixteen percent of patients with RMS and metastatic disease had isolated lung metastases. Thirty-one (67%) had more than 5 metastatic lung lesions. These were bilateral in 34 (74%). Only 6 patients were biopsied at diagnosis. Sixteen children (35%) did not receive any lung radiotherapy. Patients that received lung radiotherapy had fewer lung recurrences ( P = .04), although this has no significant impact on overall survival (OAS, 47% radiotherapy vs 31% no radiotherapy). Compared with patients with other sites of metastatic disease, patients with lung-only metastases have a greater proportion of favorable histology (67% vs 39%, P = .0017), negative nodal involvement (67% vs 32%, P = .0013), and parameningeal primaries (39% vs 12%) and a smaller proportion of extremity primaries (20% vs 33%, P = .0005 for site of primary tumor). Overall survival at 4 years for lung-only metastases was not significantly different from other single-site metastasis (42% vs 34%). Survival was not improved for unilateral disease or fewer than 5 metastatic lesions. Factors associated with diminished OAS include unfavorable histology (P = .0001) and age >10 years (P = .015).


CONCLUSIONS
Children with RMS and lung-only metastases usually present with extensive bilateral disease that is frequently not biopsied nor given protocol-recommended radiotherapy (XRT). However, outcome is comparable, although slightly better, than patients with other single-site metastasis.
Rodeberg
David
D
Division of Pediatric Surgery, Mayo Clinic College of Medicine, Rochester, MN 55905, USA. rodeberg.david@mayo.edu
Arndt
Carola
C
Breneman
John
J
Lyden
Elizabeth
E
Donaldson
Sarah
S
Paidas
Charles
C
Andrassy
Richard
R
Meyer
William
W
Wiener
Eugene
E
D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008175:Lung Neoplasms / Q000556:secondary / Q000628:therapy*; D008297:Male; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D010865:Pilot Projects; D011878:Radiotherapy; D012208:Rhabdomyosarcoma / Q000556:secondary / Q000628:therapy*; D012983:Soft Tissue Neoplasms / Q000473:pathology / Q000628:therapy*; D016019:Survival Analysis; D016896:Treatment Outcome