In early stage disease with a favourable prognosis, overall survival rates are compromised by late treatment-related mortality.rr Hence, the focus of investigation has been to reduce the intensity of first-line therapy as much as possible, whilst maintaining tumour control.
The HD10 trialr reported 2.9% of patients receiving 20Gy radiotherapy developed severe (Grade III or IV) acute toxicity, compared with 8.7% of patients receiving 30Gy (p<0.001).
A summary of the most clinically significant toxicities associated with this protocol are included in the table below.
||Incidence of event or %
||30Gy RT: 3/528 (0.6)
20Gy RT: 6/533 (1.1)
||30Gy RT: 18/528 (3.4)
20Gy RT: 4/533 (0.7)
|GI tract disorder or dysphagia
||30Gy RT: 30/528 (5.7)
20Gy RT: 16/533 (2.9)
|Respiratory tract disorder
||30Gy RT: 2/528 (0.4)
20Gy RT: 0
The HD trial by Engert et al,rreported 6.2% (n=39) of patients developed second malignancies, with 11 patients in the RT alone arm and 10 patients in the combined modality arm developing solid tumours (p=0.52). The most common solid cancers reported were small-cell lung, skin and breast cancer. The median follow up was 87 months, with 8.1% of patients dying during follow-up (see Table 1 for Causes of Death below). Late toxicity from recent trials is not available. However, it is postulated that reduced intensity of treatment will result in decreased rates of late toxicity.
Arm A - Extended Field + boost RT alone, Arm B - RT + ABVD.
© J Clin Onc 2007r