Vitreous Levels of sIL-2R Distinguishes Intraocular Lymphoma From Uveitis

Serum soluble interleukin-2 receptor (sIL-2R) does not represent a reliable biomarker for intraocular lymphoma; however, vitreous sIL-2R may be helpful in the disease’s diagnosis, according to a study published in BMC Ophthalmology. 

The study enrolled patients who underwent diagnostic vitrectomy for marked vitreous haze at a single center in Japan from April 2014 to June 2019. The patients were separated into an intraocular lymphoma group and a uveitis group, based on the pathology of their vitreous samples. The patients with intraocular lymphoma were further separated at the time of vitrectomy into patients with extraocular involvement, and patients without extraocular involvement. Researchers evaluated serum sIL-2R, intravitreal sIL-2R, MMP-2, and MMP-9 levels.

In total, 25 eyes of 25 patients (mean age, 67.9±13.2 years; 17 men, 8 women) were included in the intraocular lymphoma groups, and 15 eyes of 15 patients (mean age, 71.9±12.1 years; 10 women, 5 men) were included in the uveitis group.  

According to the report, the serum sIL-2R levels were significantly lower in the intraocular lymphoma group compared with the uveitis group (P <.05). The level of serum sIL-2R was found to be above the normal range in 20.0% and 66.7% of the intraocular lymphoma and the uveitis groups, respectively. 

Vitreous sIL-2R tended to be higher in the intraocular lymphoma group compared with the uveitis group (P =.80), the report shows. Serum sIL-2R was significantly lower in the intraocular lymphoma group without extraocular involvement compared with the intraocular lymphoma group with extraocular involvement (P <.05), while 5.9% in the intraocular lymphoma group without extraocular involvement and 50.0% in the intraocular lymphoma group with extraocular involvement demonstrated high sIL-2R value above the normal range.

Vitreous sIL-2R, MMP-2, and MMP-9 tended to be higher in the intraocular lymphoma group with extraocular involvement compared with the intraocular lymphoma group without extraocular involvement (P =.30, P <.05, P =.16, respectively).

“Serum sIL-2R is often within the normal range in [intraocular lymphoma] patients. Even if it is within the normal range, it is necessary to consider the possibility of [intraocular lymphoma],” the researchers explain. “Meanwhile, vitreous sIL-2R may be useful for diagnosis of [intraocular lymphoma]. Patients with high sIL-2R, MMP-2, and MMP-9 in the vitreous may have high metastatic capability, and it is necessary to carefully observe these patients for the development of the extraocular involvement.”

Study limitations include the inclusion of only Japanese patients and patients with idiopathic uveitis.