Semi-Automatic Volumetric and Standard Three-Dimensional Measurements for Primary Tumor Evaluation and Response to Treatment Assessment in Pediatric Rhabdomyosarcoma.

Ewelina Gowin,Danuta Januszkiewicz-Lewandowska,Katarzyna Jończyk-Potoczna,Anna Belen Larque,Paweł Kurzawa,Patrycja Sosnowska-Sienkiewicz

doi:10.3390/jpm11080717

Abstract

Current prognostic classification of rhabdomyosarcoma in children requires precise measurements of the tumor. The purpose of the study was to compare the standard three-dimensional (3D) measurements with semi-automatic tumor volume measurement method concerning assessment of the primary tumor size and the degree of response to treatment for rhabdomyosarcoma in children. Magnetic Resonance Imaging data on 31 children with treated rhabdomyosarcoma based on the Cooperative Weichteilsarkom Studiengruppe (CWS) guidance was evaluated. Tumor sizes were measured by two methods: 3D standard measurements and semi-automatic tumor volume measurement (VOI) at diagnosis, and after 9 and 17/18 weeks of the induction chemotherapy. Response to treatment and prediction values were assessed. The tumor volume medians calculated using VOI were significantly higher in comparison with those calculated using the 3D method both during the diagnosis as well as after 9 weeks of the chemotherapy and during the 17–18th week of the treatment. The volume measurements based on the generalized estimating equations on the VOI method were significantly better than the 3D method (p = 0.037). The volumetric measurements alone can hardly be considered an unequivocal marker used to make decisions on modification of the therapy in patients with rhabdomyosarcoma.

Highlights

10 patients (32%) died due to the progress of malignancy, one child died of sepsis
In the case of 9 out of 31 children (29%) the semi-automatic method covered the sum of several components due to the irregularity or multifocality of the malignancy
The tumor volume median values calculated using the semi-automatic method—volume calculation (VOI) were significantly higher in comparison with those calculated using the 3D method both during the diagnosis as well as after 9 weeks of the chemotherapy and during 17–18th week of the treatment

Summary

Introduction

Rhabdomyosarcoma (RMS) is the most common malignant solid tumor at the developmental age after neuroblastoma and nephroblastoma (Wilms tumor) [1,2,3]. Despite the significant progress in the treatment of RMS in children, treatment failure is still observed in a part of them [1]. The determination of the tumor recurrence risk group is of key importance for the selection of the applied therapy. For this purpose, the stage of disease defined before the treatment (Tumor Nodes Metastasis (TNM) Pre-treatment Staging Classification), belonging to the surgical-pathologic group (Intergroup Rhabdomyosarcoma Studies (IRS) Clinical Group

Objectives

Results

Conclusion