Hodgkin’s disease at advanced stage : the PET-scan is very powerful to adjust the treatment

sudok1/epictura

Published the 29.12.2017 at 15h35

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Keywords :

lymphomemaladie of hodgkinPET-scanDésescalade

The PET scan is a medical imaging technique, which allows measuring in three dimensions the metabolic activity or molecular of an organ or a cancer. It is also a biomarker specific to the scope and activity of lymphoma in the body.
Its relevance is so high, in some studies, it seems to be the best marker for adapting the treatment of chemotherapy. And, in particular, for “désescalader” current chemotherapy regimens (BEACOPP), which are certainly very effective but not devoid of a certain degree of toxicity. This is what emerges from a study carried out by one of the 2 main teams world of the Hodgkin and published in the journal The Lancet.

A combination of reference

Patients with Hodgkin’s disease, a form of cancer of the lymphatic system, are often treated with associations of chemotherapies. This is called ” combination chemotherapy “. In the case of Hodgkin’s disease at advanced stage, the reference protocol, very effective, consists of a series of 8 courses of BEACOPP, a combination of seven drugs (Bleomycin, Etoposide, Doxorubicin, Cyclophosphamide, Vincristine, Procarbazine, and Prednisone) in high doses (or ” BEACOPP escalated “). Some of these molecules, however, have problematic side-effect.

The PET scan, a biomarker relevant

To conduct this study, researchers included patients aged 18 to 60 years, diagnosed with Hodgkin’s disease in the advanced stage. All of these patients have had a review of PET scan after the first 2 courses of BEACOPP (PET-2 “).
Patients whose PET scan showed extensive disease, and very active after 2 courses (PET-2 positive) have received six additional cycles of BEACOPP (8 courses total), or 6 BEACOPP and rituximab (an antibody anti-t-cell conjugates (B). Patients whose PET scan showed little or no disease after 2 courses of BEACOPP (PET-2 negative) were selected at random in two groups : the first had also six additional cycles of BEACOPP protocol (normal to 8 cycles), the second has had a treatment reduced to 2 cycles (BEACOPP reduced to 4 cures in total). The protocol was then modified according to the first results.

Désescalader the treatment

Results : for patients with a positive PET scan 2 cycles BEACOPP standard 8-cycles equally well in a 5-year progression-free survival as the BEACOPP 8 cycles with rituximab (89.7 percent versus 88.1 percent, NS), and it is possible to say that the rituximab does not add anything to the BEACOPP.
For patients with negative PET scan 2 cycles, it is possible to reduce the number of treatment cycles with 4, because the progression-free survival at 5 years is equivalent to that there is 4 cycles or 8 (92,2% vs. 90,2%, NS). At the same time, the BEACOPP for 4 cycles has much less side effects in 5 years that the BEACOPP standard, either in terms of severe infections (8% versus 15%) or organ toxicity (8% versus 18%). The deaths at 5 years were not different between the 2 groups (6 versus 4) and do not testify to an escape of the disease in the group of BEACOPP ” désescaladé “.

Thus, the BEACOPP confirms to be the reference treatment in Hodgkin’s disease in advanced stage, and the addition of an anti-CD20 antibody, rituximab, which works very well in other B lymphoma, brings nothing to BEACOPP. However, the PET scan is a particularly powerful tool to be able to désescalader risk-free treatment in patients very good responders, and thus avoid their side effects sometimes disabling (pulmonary fibrosis with bleomycin).