TY - JOUR
T1 - Radiologic Response to Neoadjuvant Treatment Predicts Histologic Response in Thymic Epithelial Tumors
AU - Johnson, Geoffrey B.
AU - Aubry, Marie Christine
AU - Yi, Eunhee S.
AU - Koo, Chi Wan
AU - Jenkins, Sarah M.
AU - Garces, Yolanda I.
AU - Marks, Randolph S.
AU - Cassivi, Stephen D.
AU - Roden, Anja C.
N1 - Publisher Copyright:
© 2016 International Association for the Study of Lung Cancer
PY - 2017/2/1
Y1 - 2017/2/1
N2 - Introduction Neoadjuvant treatment might increase resectability of thymic epithelial tumors (TETs). No standardized pathologic grading scheme for tumor response is available. Also, it is unclear whether radiologic treatment response can predict pathologic response. Methods Patients with unresectable TETs who underwent neoadjuvant treatment before surgery at Mayo Clinic Rochester (1942–2014) were included. The pathologic tumor response grade (TRG) was based on Mandard grading (1994), ranging from TRG 1 (no viable tumor) to TRG 5 (no regression). TRG was compared with response by computed tomography, including with the Response Evaluation Criteria in Solid Tumors, version 1.1 (Byrne modification). Results A total of 49 patients, including 29 men, with a median age of 47.6 years and thymomas (n = 28) or thymic carcinomas (n = 21) were included. In five cases, pretreatment tumor type differed from posttreatment diagnosis. Thymic carcinomas had a greater morphologic response to neoadjuvant treatment than did thymomas with a lower percent viable tumor (p < 0.0001) and lower TRG (p<0.0001). Agreement for TRG by three reviewers was good (Krippendorff α = 0.838). By imaging (n = 24), partial response and larger reduction in tumor longest diameter and volume were associated with lower TRG (p = 0.0093, p = 0.0042, and p = 0.0021, respectively) and lower percent viable tumor (p = 0.0041, p = 0.0034, and p =0.0019). TRG correlated with radiologic change in tumor longest diameter and volume (Spearman correlation coefficient = 0.59 and 0.61, respectively). Radiologic change in tumor longest diameter and volume reasonably predicted pathologic TRG of 3 to 5 versus 1 or 2 (area under the curve 0.73 and 0.71, respectively). Sixty-seven percent of patients’ tumors were completely resected. Conclusions Our proposed histologic TRG for TETs appears easy and reproducible and correlates with radiologic response. Radiologic response is useful to predict pathologic response.
AB - Introduction Neoadjuvant treatment might increase resectability of thymic epithelial tumors (TETs). No standardized pathologic grading scheme for tumor response is available. Also, it is unclear whether radiologic treatment response can predict pathologic response. Methods Patients with unresectable TETs who underwent neoadjuvant treatment before surgery at Mayo Clinic Rochester (1942–2014) were included. The pathologic tumor response grade (TRG) was based on Mandard grading (1994), ranging from TRG 1 (no viable tumor) to TRG 5 (no regression). TRG was compared with response by computed tomography, including with the Response Evaluation Criteria in Solid Tumors, version 1.1 (Byrne modification). Results A total of 49 patients, including 29 men, with a median age of 47.6 years and thymomas (n = 28) or thymic carcinomas (n = 21) were included. In five cases, pretreatment tumor type differed from posttreatment diagnosis. Thymic carcinomas had a greater morphologic response to neoadjuvant treatment than did thymomas with a lower percent viable tumor (p < 0.0001) and lower TRG (p<0.0001). Agreement for TRG by three reviewers was good (Krippendorff α = 0.838). By imaging (n = 24), partial response and larger reduction in tumor longest diameter and volume were associated with lower TRG (p = 0.0093, p = 0.0042, and p = 0.0021, respectively) and lower percent viable tumor (p = 0.0041, p = 0.0034, and p =0.0019). TRG correlated with radiologic change in tumor longest diameter and volume (Spearman correlation coefficient = 0.59 and 0.61, respectively). Radiologic change in tumor longest diameter and volume reasonably predicted pathologic TRG of 3 to 5 versus 1 or 2 (area under the curve 0.73 and 0.71, respectively). Sixty-seven percent of patients’ tumors were completely resected. Conclusions Our proposed histologic TRG for TETs appears easy and reproducible and correlates with radiologic response. Radiologic response is useful to predict pathologic response.
KW - RECIST
KW - Thymic carcinoma
KW - Thymoma
KW - Treatment response
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U2 - 10.1016/j.jtho.2016.09.118
DO - 10.1016/j.jtho.2016.09.118
M3 - Article
C2 - 27666658
AN - SCOPUS:85015263408
SN - 1556-0864
VL - 12
SP - 354
EP - 367
JO - Journal of Thoracic Oncology
JF - Journal of Thoracic Oncology
IS - 2
ER -