Comorbidity index as a negative prognostic factor for survival in MCL

On 21 November 2018, Ingrid Glimelius from Uppsala University, Uppsala, SE, and colleagues, published in Blood a retrospective study from the Swedish Lymphoma Registry evaluating the prognostic value of certain comorbidities in mantle cell lymphoma (MCL).

MCL patients presenting with comorbidities, and especially elderly patients, have poor disease prognosis and tolerability towards intensive regimens. The aim of this population-based analysis was to identify the most common comorbidities in MCL patients and to evaluate their effect on treatment choice. The primary endpoints of the study were lymphoma-specific and overall survival (OS), as well as reasons for mortality in MCL patients.

Study design

• N = 1385 MCL patients from the Swedish registry between 2000–2015
• Age groups:
  • Less than 59 years: 24%
  • Between 60–69: 32%
  • More than 80 years: 14%
• Patients with comorbid diseases within 10 years from diagnosis were identified from the national Swedish registries, based on Charlson comorbidity index (CCI)
• Model-based predictions were used for cumulative death probability

Results

• In total, 44% of patients had ≥ 1 comorbidity at diagnosis (n = 606)
• Of those, 28% (n = 388) had ≥ 2 comorbidities (CCI = 2⁺)
• Most common comorbidities:
  • Prior malignancy (17%; prostate cancer most frequent)
  • Prior coronary heart disease (14%)
  • Diabetes (9%)
  • Pulmonary disease (7%)
  • Renal disease (3%)
  • Connective tissue disease (3%)
  • Psychiatric disorder (2%)
  • Dementia (1%)
• At a median (range) follow-up: 3.7 years (0.0–15.6):
  • n = 633 (46%) patients died from lymphoma
• Lymphoma was the major cause of death in males irrespective of their CCI but was only the main cause of morbidity in females with CCI = 0. In females with CCI ≥ 1, half of the patients dies from other causes
• A CCI of 2⁺ was significantly associated with inferior OS and lymphoma-specific survival (adjusted lymphoma-specific HR = 1.31; 95% CI, 1.04–1.65)
• Comorbidities linked to inferior lymphoma-specific survival were:
  • History of coronary disease
  • History of connective tissue disease
  • History of renal disease
  • Dementia
  • Psychiatric disorder
• Patients below the age of 70 at diagnosis and with CCI = 0, were primarily treated with R-maxi-CHOP alternating with high-dose cytarabine, rituximab, and consolidation with high-dose therapy autologous stem cell transplantation (n = 117/437; 41%)
• Patients below the age of 70 at diagnosis but with CCI = 1 (n = 24/117; 34%) or CCI = 2⁺ (n = 13/112; 12%) were mainly treated with CHOP, bendamustine or chlorambucil and rituximab

The results of this analysis indicated that almost 50% of the MCL patients in Sweden during the time of the study, presented with a comorbidity at diagnosis. The presence of two or more comorbidities was an independent prognostic factor of worse OS and lymphoma-specific survival. The investigators stated since lymphoma was the main cause of death in male MCL patients irrespective of CCI, there is a clear need for the development of efficient treatments, which should consider the effect of comorbidities like coronary heart disease, connective tissue disease, and renal disorders.