EARLY Interim FDG-PET Scan in Localised Hodgkin Lymphoma: Evaluation of Practice in 5 French Centers

Background: Long-term survival from Hodgkin lymphoma (HL) in early-stage (I–II) patients is more than 85%. However, certain patients have a primary refractory disease with a worse evolution. Early interim FDG-PET scan performed after 2 courses of chemotherapy (PET-2) provides an early and accurate assessment of response and a correlation has been demonstrated between normalization of PET-2 and patient outcome.

Aim: To evaluate the percentage of negative PET-2 in early-stage patients, and to seek clinical or biological factors predictive of positive PET-2.

Methods: Sixty-five patients from five French centers with early-stage Hodgkin lymphoma received ABVD as firstline chemotherapy. PET-2 was performed 3 weeks after the second course of ABVD. Radiotherapy and changes in management according to FDG-PET scan result could be decided by the clinician. Evaluation was retrospective.

Results: The median age was 36 years (range17–77). Thirty-nine patients were male. Seventy-three percent of patients were in unfavorable group according to EORTC criteria (one or more of the following criteria: age > 50, systemic symptoms, elevated ESR >50 mm, bulk disease and more than three lymph node areas involved). Fifty-seven patients had a pre-treatment FDGPET scan with a modification of staging in 6 cases. Initial staging according to CT scan or FDG-PET scan was as follows: IA: 5 patients, IB: no patient, IIA: 35 patients and IIB: 25 patients. Fifty-three patients (82%) had a negative PET-2 whereas 12 patients (18%) had a clearly positive PET-2. Among the 53 patients with negative PET-2, 47 patients underwent radiation therapy after completion of four courses of ABVD. Among the 12 patients with positive PET-2, treatment intensification (BEACOPP) occurred for 7 patients with a negative FDG-PET scan for 6 of them after two courses. For the 5 PET+ patients pursuing with ABVD: three had a negative FDG-PET scan and two had a positive FDGPET scan after four cycles of ABVD. At a median follow-up of 30 months, 6 patients relapsed early after the end of the treatment (2 in the negative PET-2 group and 4 in the positive PET-2 group). Out of the 7 patients of the positive PET-2 group receiving an increase dose intensity of chemotherapy (BEACOPP), 3 of them relapsed. The 59 other patients did not presented any failure or relapse at the present time.

Conclusion: We showed in this series that negative PET-2 is obtained in 82% of patients with early stage disease. These results are similar to those expected in the EORTC H10 trial which evaluates PET-2 guided treatment adaptation and expect about 85–90% of negative PET-2. This retrospective study augurs that positive TEP2 is a pejorative prognostic factor and the utilisation of the BEACOPP treatment in these population remains to define. Prospective studies, like H10 EORTC trial are warranted to confirm these results and find predictive factors for a positive PET-2.