Aims: NPC is an important cancer in people of Southern Chinese descent. Trajectories in health-related quality of life (QoL) among NPC patients following treatment are poorly documented. We describe distinct QoL trajectories during eight-months of radiation therapy among Chinese NPC patients, and factors differentiating these trajectories.

Methods: 253/514 (49%) Chinese patients with NPC scheduled for radiation therapy reported QoL (FACT-G (Chinese)) optimism, pain, eating function, and patient satisfaction at pre-treatment, and again 4-months and 8-months later. Of 253 participants, 201 (79%) and 187 (74%) completed 4-months and 8-months follow-up assessments, respectively.  Latent growth mixture modeling(LGMM) was used to identify trajectories within each of the four QoL domains: Physical, Emotional, Social/Family, and Functional well-being. Multinominal logistic regression (MLR) compared optimism, pain, eating function, and patient satisfaction by trajectory patterns adjusted for demographic and medical characteristics to identify associated variables.

Results: LGMM identified three distinct trajectories for Physical and Emotional domains, four trajectories for Social/Family domain, and two trajectories for Functional domain. In each domain, a majority (Physical 77%, Emotional 85%, Social/Family 55%, and Functional 63%) of patients showed relatively stable high QoL over the 8-month period. Significant proportions of patients experienced persistent low QoL (Physical 13%, Emotional 8%, Social/Family 21%, and Functional 37%) over time. MLR suggested Physical trajectories were differentiated by pain, optimism and disease recurrence after baseline, whereas Emotional trajectories were differentiated by pain, optimism, eating enjoyment, patient satisfaction with information, gender, and employment status. Social/Family trajectories were differentiated by martial status, appetite, optimism, employment status, and household income, whereas Functional trajectories were differentiated by household income, eating enjoyment, optimism, and patient satisfaction with information.

Conclusions: While most patients with NPC demonstrated high stable QoL, a substantial proportion of patients with persistent poor QoL experienced a pessimistic outlook, high symptom distress, unmet information needs, and were female and unemployed.