Hyperprogressive disease in patients with advanced cancer treated with immune checkpoint inhibitors.

[BACKGROUND] Hyperprogressive disease (HPD) is a new phenomenon developing in the era of immune checkpoint inhibitor (ICI) therapy. HPD is characterized by an unexpected and fast progression in tumor volume and poor survival. There is no standardized definition for HPD and clinicopathological variables associated with HPD are unclear. Herein, we assessed incidence, treatment outcomes and factors predictive of HPD in patients treated with ICIs.

[METHODS] We retrospectively analyzed patients with advanced cancer treated with ICI at one academic center between 2014 and 2021. We used the Lo Russo's adopted criteria combined with clinical and radiologic parameters for the definition of HPD. All patients who underwent their first tumor evaluation according to RECIST1.1 were included.

[RESULTS] Of 155 patients, 147 were eligible for analysis. The median age was 61 and 83% were male. The cancer types were; lung 67.3%, bladder 12.9%, gastric 9.5%, 5, colon 5.4% and renal cell carcinoma 4.8%. 59.9% of patients were treatment-naive and others had one or more lines of chemotherapy. 19 (12.9%) patients had HPD. In patients who had HPD, progression-free survival (PFS) was significantly shorter (1.5 vs 9.8 months, (HR 9.56; 95% CI (5.51-16.57), p < 0.001). The median overall survival (OS) was also shorter for HPD patients than non-HPD (3.0 vs 23.1 months, respectively, HR 12.03, 95% CI (6.64-21.81), p < 0.001). Gastric cancer, larger sum of target lesion diameters at baseline, liver metastases, higher LDH level and higher neutrophil-lymphocyte ratio (NLR) were significantly associated with HPD.

[CONCLUSION] Our findings demonstrated that HPD was a rapid phenomenon with significantly poor survival rates. Several clinicopathological factors and tumor characteristics might indicate HPD.