Methods
All patients with relapsed ALCL included in the study were initially treated in our hospital in 2016–2018. Histology confirmation was required for the diagnosis of relapsed ALCL in all patients. Detailed data on the first- and second-line treatments and the outcomes of these patients were collected from their medical files.
A cycle of therapy was defined as a 4-week interval during which vinorelbine was given as a weekly intravenous injection of 25 mg/m2 for 3 consecutive weeks (days 1, 8, and 15) followed by a 1-week rest. Steroids were combined with vinorelbine during the first 4 to 6 weeks of the treatment. At least 2 cycles of weekly vinorelbine regimen were administered unless there were signs of disease progression. After 2 cycles, a formal assessment by computed tomography (CT) or magnetic resonance imaging (MRI) scans was performed. Fluorodeoxyglucose positron emission tomography scan is recommended but not mandatory. The treatment after 2 cycles of single-drug vinorelbine therapy was at the discretion of the physician. Any further single-drug vinorelbine therapy was only to be administered if CR was achieved after the initial two cycles.
Complete remission was defined as disappearance of all evidence of disease. Unconfirmed complete response was defined as a residual lymph node mass >1.5 cm on CT scans, or MRI evaluations that regressed by >75% in the sum of the products of the greatest perpendicular diameters (SPD) of the lesions, or any residual lesions in organs that decreased by >75% with a negative PET scan. Progressive disease was defined as an increase of >25% in SPD or the development of a new lesion.
Toxicity was graded according to the Common Terminology Criteria for Adverse Events, version 3.0. Hematological and hepatic toxicity rates were estimated. Dose reductions of vinorelbine were not permitted in this protocol. Vinorelbine was withheld at either the second or third dose (days 8 or 15, respectively) of each vinorelbine cycle for an absolute neutrophil count less than 500/mm3 or platelets <50,000/mm3. If a dose was withheld, it was not repeated.