Decision analysis for prophylactic cranial irradiation for patients with small-cell lung cancer.
OBJECTIVE
Prophylactic cranial irradiation (PCI) has been shown to provide survival benefit in patients with limited disease small-cell lung cancer (LD-SCLC) who have achieved complete response. However, PCI may also produce long-term neurotoxicity (NT). The benefits and risks of PCI in LD-SCLC are evaluated.


METHODS
We developed a decision-analytic model to compare quality-adjusted life expectancy (QALE) in a cohort of SCLC patients who do or do not receive PCI by varying survival rates and the frequency and severity of PCI-related NT. Sensitivity analyses were applied to examine the robustness of the optimal decision.


RESULTS
At current published survival rates (26% 5-year survival rate with PCI and 22% without PCI) and a low NT rate, PCI offered a benefit over no PCI (QALE = 4.31 and 3.70 for mild NT severity; QALE = 4.09 and 3.70 for substantial NT severity, respectively). With a moderate NT rate, PCI was still preferred. If the PCI survival rate increased to 40%, PCI outperformed no PCI with a mild NT severity. However, no PCI was preferred over PCI (QALE = 5.72 v 5.47) with substantial NT severity. Two-way sensitivity analyses showed that PCI was preferred for low NT rates, mild NT severity, and low long-term survival rates. Otherwise, no PCI was preferred.


CONCLUSIONS
The current data suggest PCI offers better QALE than no PCI in LD-SCLC patients who have achieved complete response. As the survival rate for SCLC patients continues to improve, NT rate and NT severity must be controlled to maintain a favorable benefit-risk ratio for recommending PCI.
Lee
J Jack
JJ
Department of Biostatistics & Applied Mathematics, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030-4009, USA. jjlee@mdanderson.org
Bekele
B Nebiyou
BN
Zhou
Xian
X
Cantor
Scott B
SB
Komaki
Ritsuko
R
Lee
Jin Soo
JS
D001932:Brain Neoplasms / Q000517:prevention & control* / Q000556:secondary*; D018288:Carcinoma, Small Cell / Q000517:prevention & control* / Q000556:secondary*; D016371:Cranial Irradiation; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D008017:Life Expectancy; D016015:Logistic Models; D008175:Lung Neoplasms / Q000473:pathology*; D008297:Male; D011237:Predictive Value of Tests; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016019:Survival Analysis