The role of FDG-PET in Hodgkin lymphoma

Abstract

18-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) is currently the most valuable imaging technique in Hodgkin lymphoma. Since its first use in lymphomas in the 1990s, it has become the gold standard in the staging and end-of-treatment remission assessment in patients with Hodgkin lymphoma. The possibility of using early (interim) PET during first-line therapy to evaluate chemosensitivity and thus personalize treatment at this stage holds great promise, and much attention is now being directed toward this goal. With high probability, it is believed that in the near future, the result of interim PET-CT would serve as a compass to optimize treatment. Also the role of PET in pre-transplant assessment is currently evolving. Much controversy surrounds the possibility of detecting relapse after completed treatment with the use of PET in surveillance in the absence of symptoms suggestive of recurrence and the results of published studies are rather discouraging because of low positive predictive value. This review presents current knowledge about the role of 18-FDG-PET/CT imaging at each point of management of patients with Hodgkin lymphoma.

Keywords: Hodgkin lymphoma; interim PET; positron emission tomography; restaging; staging.

Fig. 1

CT (A) and PET (B) coronal images show a case of 35-y-old man with classical HL upstaged by PET-CT. Enlargement lymph nodes in mediastinum was reported on CT (stage 2). The PET scans showed multifocal uptake in bone marrow (stage 4). See arrows. Axial PET-CT images demonstrate lesions: in the right pubic bone (C), in the right femur (D) and in the left rib (E). Axial CT images in the same localizations show no irregularities (F, G, H)

Fig. 2

Sequential PET images from patient with classical HL who achieved complete metabolic remission (CMR). A) Baseline PET of 47-y-old man with stage III. Patient initially had involvement of cervical and axillary regions, mediastinum and lymph nodes in abdomen and pelvis. B) Interim PET (after 2 cycles ABVD). Patient had persistent active disease in axillary lymph nodes (arrows), where FDG uptake was moderately higher than that in liver (score 4, positive according to 5PS). C) End-of-treatment PET (after 6 cycles ABVD). Lymph nodes showed FDG uptake below than that in mediastinum (score 2, negative according to 5PS)

Fig. 3

Sequential PET images from patient with classical HL who not achieved CMR. A) Baseline PET of 36-y-old women with stage IV bulky. Patient initially had involvement of lymph nodes above and below diaphragm with bulky disease in mediastinum and abnormalities in lung, spleen, bone and bone marrow. B) Interim PET after 2 cycles ABVD, and C) End-of-treatment PET after 8 cycles ABVD: Patient had persistent active disease in residual mass in mediastinum (arrows). CT (D) and PET-CT (E) images indicate abnormal mass in traverse section. PET-CT demonstrated pathologic FDG uptake in the nodal mass, higher than that in liver (score 4, positive according to 5PS)

Fig. 4

PET (A), PET-CT (B) coronal images and axial CT (C) and PET-CT (D) scans show a case of 22-year-old man with stage IIA bulky classical HL who achieved CMR after combined-modality treatment. PET-CT was done in surveillance, 7 months after completed therapy, without any clinical suspicious of disease relapse and revealed pathologic FDG uptake (score 4 according 5PS) in residual mass in mediastinum (arrows). A biopsy was negative and patient remains free of disease