Using TARC blood levels to predict treatment success for patients with Hodgkin lymphoma

This study looked at how well thymus and activation-regulated chemokine (TARC) levels can predict outcomes for patients with Hodgkin lymphoma. The authors concluded that an early reduction in TARC levels can predict that treatment will be successful. 

Hodgkin lymphoma (HL) is generally considered a curable disease. Current research focuses on reducing treatment intensity to reduce negative outcomes associated with treatment. It is important to be able to predict whether treatment will be successful so that patients who have a poor prognosis can receive more intense treatment and those who have a good prognosis do not receive extra unnecessary treatment.

Thymus and activation-regulated chemokine (TARC) is a signaling protein that is expressed by HL cells. Low TARC levels in a patient’s blood after treatment may indicate that the treatment was successful. More research is needed to determine if TARC levels can predict if a treatment is successful. 

116 patients were recruited for this study. 101 were included in the final analysis. All patients with stage I or IIA disease received ABVD chemotherapy (adryamicin, bleomycin, vinblastine, and dacarbazine).  All patients with stage IIB, III, or IV disease received ABVD and BEACOPP (bleomycin, etoposide, adryamicin, cyclophosphamide, vincristine, procarbazine, and prednisone) if they continued to have HL after initial treatment. The average length of follow up was 65 months.

Before treatment, the average TARC level was 27,515 pg (picogram)/ml. The average TARC for healthy people is 318 pg/ml. After treatment, the average TARC level of all the patients was 556 pg/ml.

The study gave a cut-off point of 800 pg/ml for TARC blood levels. Below 800 pg/ml is considered low. Patients with a TARC level below 800 pg/ml were significantly more likely to have their treatment be successful.

Patients with a TARC below 800 pg/ml were also more likely to have better progression free survival (time from treatment to disease progression). The 5-year progression-free survival for patients with a low TARC was 90.1%. The 5-year progression-free survival for patients with a high TARC (above 800 pg/ml) was 55.6%. This was true for both patients with early stage and patients with advanced stage disease. 

The authors concluded that TARC blood levels are a good method of predicting treatment success and are good predictors of progression free survival.