Prevalence of Histopathologically Diagnosed Ophthalmic Neoplastic Lesion Among Opthalmic Biopsies in a Pathology Laboratory of a Tertiary Care Hospital

ABSTRACT Introduction: Many vision threatening or life threatening neoplastic conditions often mimic less aggressive neoplastic or non-neoplastic inflammatory variants. This study aims to comprehensively analyze the histopathological spectrum of ophthalmic neoplastic lesions tumors in a pathology laboratory in a tertiary care hospital. Methods: A descriptive cross-sectional study was conducted in the Department of Pathology at Birat Medical College and Teaching Hospital, Morang, Nepal over a period from November 2016 to October 2018. Ethical clearance was taken from Institutional Review Committee of Birat Medical College. Sample size was calculated and convenience sampling was done. Data was collected in excel and analyzed in Statistical Package for Social Sciences version 16. Point estimate at 95% Confidence Interval was calculated and frequency and percentage was calculated for binary data. Subgroup analysis was done based on age, sex, nature of lesions and site of lesions. Results: Prevalence of ophthalmic neoplastic lesion was 139 (55.37%), of which 74 (53.24%) were benign and 65 (46.76%) were malignant. Benign was mostly seen in females and of second decade and malignant was common in males and seventh decade of life respectively. Nevus in 18 (24.3%) and squamous cell carcinoma in 30 (17.6%) was found to be the most common benign and malignant lesions among the specimens. Conjunctiva and cornea in 52 (37.41%) was the most common location for those neoplastic lesions. Conclusions: The most common ophthalmic neoplastic lesion was benign. Nevus is common in females and second decade and squamous cell carcinoma is common in males and seventh decade of life.


INTRODUCTION
Among the few special sensory organs of our body, the eye proves to be a unique and special sensory organ exhibiting diverse histologic structures. The related knowledge of normal ocular anatomy along with the pattern following its pathologic changes that involve these structures is mandatory. Ophthalmic biopsies generally fall among as it encompasses a wide range of tissue division and diseases making the task ever more challenging. Hence, histopathological evaluation is warranted as there is a need to differentiate them before definitive therapy is planned. 2 The aim of the study is to find the prevalence of histopathologically diagnosed ophthalmic neoplastic lesion in a tertiary care centre in eastern Nepal.

METHODS
This is a descriptive cross-sectional study conducted in the Department of Pathology of Birat Medical College and Teaching Hospital, Morang in the eastern region of Nepal, over a period commencing from November 2016 to October 2018. The research has been conducted after receiving the institutional clearance. The inclusion criteria were all the ophthalmic surgical samples received irrespective of age and sex during the study period.
Sample size was calculated using the following formula, n = Z 2 x p x q/e2 = (1.96) 2 x o.5 x 0.5/(0.09) 2 = 119 where, n = sample size p = prevalence, 50% q = 1-p d = margin of error, 9% Z = 1.96 at 95% CI The minimum sample size calculated was 119. Non random sampling has been done so the sample size was doubled to 238. Thus, the final sample size taken was 251. Data was entered in Microsoft Excel and analyzed in SPSS version 16. Subgroup analysis was done based on as age, sex, nature of lesions and site of lesions.

RESULTS
Prevalence of ophthalmic neoplastic lesion were 139 (55.37%), 74 (53.24%) benign and 65 (46.76%) malignant tumors were analyzed. All the malignant neoplastic lesions were found to be primary neoplastic lesion. None of the specimens were found to be metastatic. The observations and results of the study are as follows. Benign tumours were slightly more common than the malignant tumours (Table 1). The benign lesions were slightly more common in female. Similarly, malignant lesions were more common in male patients ( Table 2). In the study, the benign neoplasms were found to be more common in the second decade of life, while malignant neoplasms were most common in the seventh decades of life (Table 3).  Squamous cell carcinoma (46.16%) and conjunctival intraepithelial neoplasia (7.0%) followed by ocular surface squamous epithelial neoplasia with dysplasia (7.0%) were the most common malignant lesions among the specimens investigated (Table 5). Anatomically classifying, the neoplastic lesions of conjunctiva and cornea (37.41%) were the most common while lacrimal gland (2.16%) was the least common. (Table 6). Our study demonstrated that the lesions had preponderance towards male than female (1.5:1). Similar kind of study done by S Pudasaini et al in the central part of Nepal has also reported ophthalmic neoplastic lesions being more common in male than female. 8 This has also been further supported by other studies done by Sunderraj P et al. and Bastola PS et al5 who have both described the lesions occurring more in males than females. 9 Our study also showed the benign and malignant neoplasms being more common in the second and seventh decades of life respectively. In our study, benign ophthalmic lesions were highest among the age group 11-20 years, while malignant lesions were common in the age group 61-70 years. Sheikh IY et al have also reported similar finding where they have reported the benign neoplasms being more common in the second decade of life while malignant neoplasms had a bimodal peak in first and seventh decades of life. 4 Among the benign lesions in our study, nevus was the most common benign ophthalmic neoplasms (24.3%) followed by hemangioma ( In another regional study conducted by Jahagirdar SS et al, they observed 37% sebaceous (meibomian) carcinoma and 44% basal cell carcinoma. 10 Although sebaceous carcinoma, conjunctival intraepithelial neoplasm and ocular surface squamous neoplasm were found to be very common in our study, the frequency was not as they have mentioned. Thakur SK et al. reported retinoblastoma (45.2%) as the most common malignant ophthalmic lesion observed. 11 In our study, there was the only one case of retinoblastoma.
Conjunctival and corneal location (37.41%) was the most common site of occurrence for the ophthalmic neoplasm in our study, followed by eyelid (35.97%) and limbus (11.51%) respectively. Ud-Din N, et al in their study reported a maximum number of lesions from eyelids (36.36%) followed by conjunctiva (28.79%), and least was seen from lacrimal gland and passages. 3 The lacrimal gland was found to be the least common site for neoplasm in our study and supports this finding.
The limitation of the study is that the study has been done in small settings so findings cannot be generalized. Similarly, reporter's bias cannot be excluded.

CONCLUSIONS
The benign ophthalmic lesions were more common than the malignant lesions, with slightly more female preponderance. The benign neoplasms were found to be more common in second decade of life followed by malignant lesion being most common in the seventh decade of life.
The ophthalmic neoplastic lesions were mainly found in conjunctiva and cornea with pathological variants such as nevus and squamous cell carcinoma being more common lesions respectively. As histopathology remains the gold standard and mainstay of diagnosis in neoplastic growth, so all surgically removed ophthalmic neoplasms/tissues should be proposed and subjected for regular histopathological examination.