Pediatric Osteosarcoma Pulmonary Metastases

Agenda Background Metastatic workup Evidence for metastectomy Prognostic indicators Survival Summary

Etiology Most common primary bone tumor in kids Age black males most at risk 400 cases/yr in US (age <20) Multiple subtypes (treated the same) Usually distal femur or proximal tibia 15-20% present with mets – 85% are pulmonary – 80% of local-only tumors likely have micromets

Imaging

CT ~80% sensitive >6mm and 60% if less (Margaritora, Eur J CT Surg 2002) CT may miss 1/3 of lung lesions (Kayton, J Ped Surg, 2006)

Pulm met criteria

Timing of Dx of Mets Tsuchiya, JCO, 2002

First Recurrence 576 pts with recurrence after initial CR 501 w/ mets (469 lung) Median f/u 1.2 yrs, 4.2 yrs for survivors

Overall Survival OS: 5yr: 23% 10yr: 18%

Importance of R0

Prognostics factors

Subsequent Recurrences 249 pts with nd or subsequent recurrences 93 with 3rd 38 with 4 th 14 with 5th

Bielack, JCO, yr OS: 1 st 2 nd 3 rd 4 th 5 th 23%16%13%14%18%

Risk for Recurrence Bielack, JCO, 2009

Timing of recurrence 137 pts at single institution (MDACC) 99 resections OS for resection vs non (33months vs 10months)

5yr OS: 56% 5yr OS: 12%

Overall Survival Harting, Sem Peds Surg, 2006 Earlier study suggested 82% vs 13% (Goorin, JCO, 1984) *78% unilateral will develop contralateral disease ( Su, J Peds Surg, 2004) *

Controversies Bilateral disease – Staged vs. synchronous Exploration contralateral side

Summary Osteosarcoma often metastatic to lung Benefits from aggressive resection Repeat resections show continued benefit Open approach better Need CR (no ink on tumor) Short DFI, bad Px