by ecancer reporter Janet Fricker

Use of chemotherapy without additional radiotherapy for patients with Hodgkin lymphoma (HL) is associated with a lower risk of developing a second cancer, concluded a Cochrane meta-analysis study published September 13.

The advantage, however, was gained at the cost of more growth or regrowth of disease.

Since HL often affects young people and highly effective treatments allow most patients to survive long after diagnosis, curing disease has to be weighed against the risk of causing long-term adverse effects, such as secondary cancers.

For the Cochrane review, Jeremy Franklin, from the University Hospital of Cologne, Germany, and colleagues, identified 16 clinical trials which treated HL patients between 1984 and 2007.

The options included use of chemotherapy with or without additional radiotherapy; use of more extensive or more restricted radiation fields; use of a higher or lower radiation dose;  use of more or fewer courses of chemotherapy and use of standard-dose or dose-intensified types of chemotherapy.

Results showed omitting additional radiotherapy probably reduces secondary malignancy incidence (Peto odds ratio (OR) 0.43, 95% CI 0.23 to 0.82), corresponding to an estimated reduction of eight-year SMN risk from 8% to 4%.

There was a slightly higher rate of PFS with the combined modality, but confidence in the results was limited by high levels of statistical heterogeneity between studies (HR 1.31, 95% CI 0.99 to 1.73).

In the comparison of chemotherapy plus involved-field radiation versus same chemotherapy plus extended-field radiation (early stages), neither second cancer risk, survival or HL-free survival was markedly different.

In the comparison of chemotherapy plus lower-dose radiation versus same chemotherapy plus higher-dose radiation (early stages), neither second cancer risk, survival or HL survival was markedly different.

In the comparison of fewer versus more courses of chemotherapy (early stages), either second cancer risk, survival or HL free survival was markedly different.

Additionally, evidence suggesting improved survival with intensified chemotherapy was not conclusive, although escalated-dose BEACOPP appeared to lengthen survival.

“Consolidating radiotherapy is associated with an increased rate of secondary malignancies; therefore it appears important to define which patients can safely be treated without radiotherapy after chemotherapy, both for early and advanced stages,” write the authors.

Due to the limited amount of long-term follow-up in the meta-analysis, they add, further long-term investigations of late events are needed, particularly with respect to secondary solid tumours.

Source: Cochrane