Three-dimensional evaluation of chemotherapy response in malignant pleural mesothelioma.
OBJECTIVE
Measurement of tumor response to chemotherapy in malignant pleural mesothelioma (MPM) is problematic because of non-spherical tumor growth patterns and difficulty in choosing target lesion. In this study, we aimed to determine the effectiveness of tumor volume measurement for evaluating chemotherapy response.


METHODS
Fifty-seven MPM patients were included. Chemotherapy responses were evaluated by computed tomography (CT) using volumetric method, World Health Organization (WHO), and modified Response Evaluation Criteria in Solid Tumor (RECIST). The tumor volume was measured using the Cavalieri principle of stereological approaches.


RESULTS
According to the volumetric method, median survival was 10.0 months for progressive disease (PD), 14.0 months for stable disease (SD) and 16.0 months for objective response (OR). According to the WHO method, median survival was 11.3, 14.0, and 13.0 months, respectively. For modified RECIST, median survival was 10.0, 14.0, and 14.0 months, respectively. The correspondence between the WHO and modified RECIST methods was substantial (K=0.66), as was that between the volumetric and WHO methods (K=0.64); however the correspondence between the volumetric and modified RECIST methods was only moderate (K=0.52).


CONCLUSIONS
The most suitable chemotherapy response measurement technique is the volumetric method because of non-spherical tumor growth patterns in MPM. However, larger studies should be performed to better establish the suitability of this method. We recommend our method for determining the chemotherapy response in mesothelioma cases. However, modified RECIST criteria can also be applied due to favourable prediction of survival, ease of application, and moderate correspondence with the volumetric method.
Ak
Guntulu
G
Department of Chest Disease, Eskisehir Osmangazi University, Medical Faculty, Eskisehir, Turkey. guntuluak@yahoo.com
Metintas
Muzaffer
M
Metintas
Selma
S
Yildirim
Huseyin
H
Ozkan
Ragip
R
Ozden
Hilmi
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008654:Mesothelioma / Q000188:drug therapy*; D008875:Middle Aged; D009367:Neoplasm Staging; D010997:Pleural Neoplasms / Q000188:drug therapy*; D011379:Prognosis; D016896:Treatment Outcome; D047368:Tumor Burden / Q000187:drug effects
D000970:Antineoplastic Agents