Nucl Med Mol Imaging.
2013 Dec;47(4):249-256.
18F-FDG PET in Patients with Primary Systemic Anaplastic Large Cell Lymphoma: Differential Features According to Expression of Anaplastic Lymphoma Kinase
- Affiliations
-
- 1Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. jsryu2@amc.seoul.kr
- 2Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
- 3Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
- 4Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Abstract
- PURPOSE
Primary systemic anaplastic large cell lymphoma (ALCL) is divided into two entities according to the expression of anaplastic lymphoma kinase (ALK). We investigated 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) findings in primary systemic ALCL according to ALK expression.
METHODS
Thirty-seven patients who had baseline PET before CHOP (cyclophosphamide, doxorubicin, vincristine and prednisolone)-based chemotherapy were enrolled. Among them, patients who underwent interim and/or post-therapy PET were further investigated for the treatment response and survival analysis. Baseline PET was analyzed visually and semi-quantitatively using peakSUV, and interim and post-therapy PETs were visually analyzed.
RESULTS
All cases were 18F-FDG-avid on baseline PET. The peakSUV of ALK-positive ALCL (n=16, 18.7+/-10.5) was higher than that of ALK-negative ALCL (n=21, 10.0+/-4.9) (P=0.006). In ALK-negative ALCL, complete response (CR) rate in negative-interim PET was higher than positive-interim PET (100 % vs 37.5 %, P=0.02); however, there was no such difference in ALK-positive ALCL (100 % vs 75 %, P=0.19). The 3-year progression-free survival (PFS) was not significantly different between ALK-positive and ALK-negative ALCL (72.7 % vs 47.6 %, P=0.34). In ALK-negative ALCL, negative interim and post-therapy PET patients had better 3-year PFS than positive interim (83.3 % vs 25.0 %, P=0.06) and post-therapy PET patients (70.0 % vs 20.0 %, P=0.04). In contrast, ALK-positive ALCL had no such differences between PFS and PET results.
CONCLUSIONS
On baseline PET, all cases showed 18F-FDG-avidity, and ALK expression was related to higher 18F-FDG uptake. ALK-positive patients tend to have better PFS than ALK-negative patients. Negative-interim PET was a good indicator of CR, and interim or post-therapy PET was helpful for predicting the prognosis only in the ALK-negative group.