Programmed death receptor Ligand 1 expression in eyelid sebaceous carcinoma: a consecutive case series of 41 patients

Abstract

Purpose: A limited number of therapies are available for patients with metastatic eyelid sebaceous carcinoma (SC). Programmed death receptor Ligand 1 (PD-L1) expression and its clinical significance in sebaceous cell carcinoma are presently unknown. This study aimed to evaluate the expression level of PD-L1 in SC.

Methods: This single centre, retrospective, and comparative study was conducted at the Ninth People's Hospital between August 1, 2013 and September 1, 2016. Twenty primary, 11 recurrent, and 10 lymph node metastatic eyelid SCs of 41 consecutive patients and paired control eyelid samples were enrolled in the study. Immunohistochemical staining of PD-L1 was performed on slides containing SC embedded in paraffin wax. Patient clinical characteristics and PD-L1 expression related to SC prognostic values were evaluated.

Results: Of the 41 patients with eyelid SCs, 58.5% (24/41) were female, and 41.5% (17/41) were male. A total of 43.9% (18/41) were left-sided, and 56.1% (23/41) were right-sided. A total of 2.4% (1/41) of the SCs were located at the canthus, 51.2% (21/41) were located at the upper eyelid, 41.5% (17/41) were located at the lower eyelids, and 2.4% (1/41) invaded the lacrimal sac. A total of 24.4% of the SCs were metastatic (10/41), 48.8% (20/41) were primary tumours, and 26.8% (11/41) resulted from recurrence. A total of 48.8% (20/41) were moderately graded and 51.2% (21/41) were poorly graded. Programmed death receptor Ligand 1 (PD-L1) positive expression was found in 20 (48.8%) cases. Programmed death receptor Ligand 1 (PD-L1) expression was observed on the tumour cell membrane. Higher expression of PD-L1 was correlated with metastatic cases when compared with primary cases (F = 6.69, p = 0.001). There was a higher expression of PD-L1 in the poorly differentiated group compared with the moderately graded group (57.1% poorly graded versus 45.0% moderately graded).

Conclusion and relevance: Inhibition of PD-L1 expression may be a therapeutic option for metastatic eyelid SCs, although this hypothesis needs to be tested in future clinical trials.

Keywords: eyelid; metastasis; programmed death receptor ligand 1; recurrent; sebaceous carcinoma.