De Luca ML, et al. APL 2017:PO038

APL in patients aged >70 years: Real-life results

Background

In the treatment of very elderly patients with acute promyelocytic leukemia (APL), very few cases have been described in a real-life setting. Therefore, at the 7th International Symposium on APL, De Luca and colleagues evaluated the clinical features and followed up with patients aged >70 years who were treated with arsenic trioxide (ATO) plus all-trans retinoic acid (ATRA), idarubicin plus ATRA, or ATRA alone.1

Study design

  • Patients aged >70 years were consecutively diagnosed and treated at the Università “La Sapienza” di Roma from January 1991 to June 2017.
  • Patients’ clinical features were examined and followed up throughout the treatment process.
  • Patients received induction therapy consisting of idarubicin plus ATRA, ATO plus ATRA, or ATRA alone.
  • After the induction phase, patients who achieved complete remission (CR) received consolidation therapy with chemotherapy, chemotherapy plus ATRA, ATO plus ATRA, or ATRA alone.

Key findings

Clinical features

  • A total of 22 patients were evaluated for clinical features.
  • The median age at diagnosis was 74.9 years (range: 70.0–85.4).
  • There were 17 patients with the M3 APL subtype and five patients with the M3 variant subtype.
  • The median white blood cell count was 1.3 x 109/L (range: 0.6–286).
  • According to the Sanz risk score, nine patients were at low risk, eight patients were at intermediate risk, and five patients were at high risk.
  • In terms of major comorbidities, 6 of the 22 patients had concomitant pulmonary diseases, 10 had arterial hypertension, 7 had a concomitant cardiologic disease, 3 had diabetes mellitus, and 9 had a previous malignancy.

Induction

  • Two patients (9.0%) died very early after admission from gastrointestinal bleeding and fatal cerebral hemorrhage, respectively, and did not receive induction therapy.
  • A total of 20 patients received induction therapy:
    • Twelve patients received idarubicin plus ATRA; of which, five patients required idarubicin dose reduction.
    • Three patients received ATO plus ATRA.
    • Five patients received ATRA alone, but two patients needed to add chemotherapy (mitoxantrone and cytarabine) to the treatment due to hyperleukocytosis.
  • There were 18 patients (90%) who achieved morphological CR after a median time of 45 days (range: 28–66).
    • A total of 16 patients also achieved molecular CR after a median time of 118 days (range: 51–239).
    • The remaining two patients had not yet had a molecular evaluation.
  • Infective complications were observed in 16 of the 20 patients (five episodes of fever of unknown origin, six sepsis cases, three cystitis cases, four pneumonitis cases, and one oral abscess case).
  • ATRA syndrome occurred in 6 of the 20 patients.
  • There were three episodes of respiratory failure, five episodes of arrhythmia (two paroxystic atrial fibrillations and one QT prolongation), and one episode of cardiac ischemia.

Consolidation and maintenance

  • A total of 16 patients in CR received consolidation therapy:
    • Seven patients received chemotherapy alone;
    • Five patients received chemotherapy plus ATRA;
    • Three patients received ATO plus ATRA; and
    • One patient received ATRA alone.
  • After consolidation, 9 of the 16 patients received maintenance treatment.
  • The remaining two patients in CR who did not receive consolidation therapy directly underwent maintenance treatment.
  • Four patients had a hematological relapse after 7, 8, 11, and 35 months, respectively; two patients had a molecular relapse after 12 and 56 months, respectively.
  • At present, 12 patients are still alive; four patients died due to disease progression (three patients) or senectus while in CR (one patient); two patients were lost to follow-up while in molecular CR.
  • The 3-year cumulative event-free survival for all patients was 58.9% (95% CI: 36.5–81.3). (Figure 1)
  • The 3-year cumulative overall survival for all patients was 63.2% (95% CI: 40.8–85.6). (Figure 2)

Figure 1. Three-year cumulative event-free survival for all patients

Figure 2. Three-year cumulative overall survival for all patients

Key conclusion

  • ATRA-based treatment of APL is safe and effective in elderly patients over 70 years old, with long-lasting disease-free and overall survival.

Reference: 1. De Luca ML, Latagliata R, Breccia M, et al. Acute promyelocytic leukemia (APL) in patients aged >70 years: Real-life results. Intl. Symposium on APL Abstracts 2017:PO038.