Alterations in tears aqueous layer during cytostatics treatment

Introduction
The aim of the study was to evaluate tears secretion, pH and lysozyme activity in tears aqueous layer during chemotherapy in lung, breast and bowel cancer.

Material and methods
6 patients were enrolled to the study. Depending on the type of cancer and type of chemotherapy patients were divided into three groups. Group I (12 patients) diagnosed with non-small-cell lung cancer treated with PE schema (cisplatin, etoposide), Group II (12 patients) with breast cancer treated with FAC schema (fluorouracil, doxorubicin, cyclophosphamide), Group III (12 patients) with bowel cancer treated with FU/LV schema (fluorouracil, leucovorin). In all the patients: Schirmer’s I test, pH measurements and lysozyme test were performed. Patients were examined before chemotherapy, after 2nd, 4th, 6th cycle.

Results
In group I and II lowering of tears secretion (p<0.001) was revealed. In group III there was higher tears secretion (p<0.001). PH was lowered after 2nd chemotherapy course in group I and II. In further treatment pH value were in the same lower level as after the second course. In group III there was higher pH – more alkaline (p<0.001) after 2nd cycle of treatment and it was on the same level to the end of the examination process. Lowering of lysozyme activity in the tears film in all groups (p<0.001) was established. The higher alterations of the lysozyme activity were observed in group treated with FAC schema.

Conclusions
Cytostatic treatment has major influence on tears aqueous layer causing alterations of tears secretions. PH alterations depending on type of chemotherapy was observed. Lowering of lysozyme activity in tears was observed. All the deteriorations aggravate with duration of chemotherapy. Alterations of tears film parameters during chemotherapy may influence upon eye surface homeostasis and infectious complication.