Photo Credit: Md Saiful Islam Khan

Thanks to new treatments, more people survive histiocytic neoplasms, but their survival comes with challenges, according to findings published in Blood.

“Advances in targeted therapeutics for histiocytic neoplasms have led to a growing survivor population, especially for Erdheim-Chester disease (ECD), Langerhans cell histiocytosis (LCH), and Rosai-Dorfman disease (RDD),” lead study author David Pottinger, MD, and coauthors wrote in oncoBlood. “This growing population is at risk of adverse HRQOL as a result of the disease or treatments received.”

“This group of rare, heterogeneous disorders is characterized by tissue infiltration of histiocytes, leading to a wide range of clinical symptoms. While much has been learned about the biology and treatment of histiocytic disorders, little is known about their impact on health-related quality of life,” explains Natasha Galanina, MD, a hematologist who was not involved in the study.

Between August 2022 and April 2023, Dr. Pottinger and his colleagues enrolled 77 participants at two histiocytosis centers and one international conference. Of these, 33 (42.9%) had ECD, 21 (27.3%) had LCH, 19 (24.7%) had RDD, and 4 (5.2%) were classified as “other/unknown.” At diagnosis, the patients ranged from 9 to 79 years, with a median of 50 years. When participants took a survey, a median of 4 years after diagnosis, they ranged in age from 18 to 82 years, with a median of 54 years.

Overall, 13 (16.9%) participants had unifocal extent, 8 (10.4%) had single-system multifocal extent, 3 (3.9%) had single-system lung LCH, and 53 (68.8%) had multisystem disease.

The most involved organs were bone in 44 (57.1%) patients; kidney, skin, and the central nervous in 24 (31.2%) patients; and pituitary in 19 (24.7%) patients.

Study participants completed the validated PROMIS (Patient-Reported Outcomes Measurement Information System) 29+2 profile v2.1 questionnaire, which uses T-scores to assess eight domains of physical health (PH) and mental health (MH) and to generate a PROMIS-Preference (PROPr) score of overall HRQOL. The researchers used multinomial logistic regression to identify relationships between characteristics and scores.

Mean PH and MH summary scores in several diagnostic categories were lower than the scores from the general US population, and PROPr scores were reduced in all diagnostic categories (Figure). Bone involvement was linked with poorer PH (P=0.005), MH (P<0.001), and PROPr (P=0.003) scores. CNS involvement was linked with poorer PH (P=0.016).

Poorer PH score was linked with involvement of bone (OR, 6.19; 95% CI, 1.88-20.43; P=0.003) and with central nervous system (OR, 10.36; 95% CI, 2.01-53.39; P=0.005).

Poorer MH scores were linked with female sex (OR, 4.12; 95% CI, 1.24-13.66; P=0.021) and CNS involvement (OR, 10.74; 95% CI, 2.47-46.79; P=0.002). CNS involvement was linked with worse odds of having a low PROPr score (OR, 10.46; 95% CI, 2.17-50.37; P=0.003).

As Disease Become Chronic, Ongoing Assessment Is Warranted

“The study highlights the importance of QOL and mental well-being assessments throughout the course of treatment for these chronic conditions,” Dr. Galanina says. “Interestingly, the scores were particularly low among patients with ECD and women.”

The findings underscore “that our efforts to bring novel, biologically informed, targeted therapies to our patients should be done in the context of multidisciplinary care to better address all our patients’ needs,” she adds.

The authors recommend further related research to assess the impact of treatments on HRQOL, and the economic losses due to lower productivity indicated by low PROPr scores.

“The study is a great start to objectively quantify the impact of these diseases and their manifestations on quality-of-life metrics,” Dr. Galanina notes. “However, as our treatment options continue to expand, it would also be helpful to measure the impact of therapy and its associated side effects on physical and mental health.”