Synovial sarcoma (SS) of childhood is considered chemoresponsive, what frequently leads to conservative surgical approach. Aim of the report is to assess whether that approach is sufficient and what are other clinical factors influencing the outcome. Patients: 23 children (aged 3 months – 17 years) treated in 5 cooperating centres for nonmetastatic SS located in the limbs(Fu>
36 months). Treatment: primary or secondary resections, chemotherapy and radiotherapy (in case of resection R1 or R2 or relapse). Locations of tumours: thigh/6, shank/1, popliteal fossa/4, cubital fossa/3, axilla/2, forearm/2, foot/3, arm/1, hand/1. Primary R0 achieved in 3, R1/5, R2/3. Twelve after initial biopsy and 3 after primary R2 were submitted to chemotherapy and secondary surgery. 12/15 those resections were R0, 3/15 R1. Two of them underwent mutilating resections. Results: 11 pts are in CR. 12 relapsed (7 local, 5 metastatic). Initial locations of the relapsing tumours were around joints/4, foot/hand 4, thigh 3, arm 1. Seven of them died despite aggressive re-treatment, 2 are alive with disease, 3 are in second CR. Quality of resections (primary or secondary) in 7 locally relapsing pts were R0 in 3, R1 in 3 and biopsy only /1 (CR after CHT alone, refused local treatment). Of 2 submitted to mutilating resections, 1 relapsed in the lungs (2nd CR after re-treatment and metastasectomy).
R0 doesn’t prevent from local relapse (3 of 7 pts relapsed after R0 vs 4/7 with R1). Mutilating resections (amputations) were unfrequent (2) and were not followed by local relapses. One metastatic relapse occurred and was finally cured. Locations at risk seemed joints and distal parts of limbs (8/12 of the relapsing pts). Relapsed implied weak chance for long-term second CR (3/12).
Tempting results of preliminary reports from EURAMOS-1 Study Group and our willingness to join the Consortium were the reason why we decided to start the pilot study exploit EURAMOS-1 protocol (approved by Local Ethical Commission). Since November 2006, 41 patients were enrolled into study (20F/21M, mean age: 14, SD: 3,02) but 1 adolescent refused the treatment at all in 2nd week on. The main localization was thigh (20/41, 49%), followed by tibia (15/41, 37%), fibula (3/41, 7%) and humerus (3/41, 7%). Majority of them had localized disease (27/41, 66%), whereas in 34% (14/41) lung metastases (LM) were revealed at diagnosis. Out of 40, 35 underwent surgery (2 amputations, 33 endoprosthesis) in 11th protocol week as average (mean: 12, SD: 2.80). Among the remaining 5 children, 4 progressed yet during neo-adjuvant CHT and 1 had to finish because of MTX intolerance. Up to now HP examination were completed in 29 children and the median of 12% of viable tumor cells remains (mean: 13%, SD: 22.32%; min. <
1%, max. 90%). Fourteen (48%) good responders continued on MAP arm. Children in whom poor HP response has been confirmed as well as all children with LM, received chemotherapy according to MAPIE arm. The switch between MAP and MAPIE proceeded in 18th week of protocol in average (median: 17th; nim. 14th, max. 24th week). Up to date, in 5 out of 21 patients completed the protocol, the treatment had to be finished untimely because of toxicity and further 5 required CHT switch because of progression. Comparing achieved HP responses with previous experiences, we found no statistically significant differences in rate of tumor necrosis in current study (48%) as in previously used regimens (EORTC 49% and SFOP 44%; OR{EURAMOS/EORTC}=0.96; OR {EURAMOS/SFOP}=1.17; chi-square=0.343, p=0.842), but the general remarks from the pilot justify study’s continuation.
