Prevalence of Histopathologically Diagnosed Ophthalmic Neoplastic Lesion Among Ophthalmic Biopsies in a Pathology Laboratory of Tertiary Hospital of Nepal.

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 these rare biopsy samples that any histopathology section of a pathology department receives.[1]

The ophthalmic pathology is unique in many aspects 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 = Z2 × p × q/e2

= (1.96)2 × 0.5 × 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).

Table 1

Distribution ophthalmic lesions. of benign and malignant

Nature of lesions	n (%)
Benign	74 (53.24)
Malignant	65 (46.76)

The benign lesions were slightly more common in female. Similarly, malignant lesions were more common in male patients (Table 2).

Table 2

Sex wise distributions of ophthalmic lesions.

Ophthalmic Neoplastic Lesions	Male n (%)	Female n (%)
Benign	34 (45.94)	40 (54.06)
Malignant	39 (60.00)	26 (40.00)
Total	73 (52.52)	66 (47.48)

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).

Table 3

Age wise distributions of ophthalmic lesions (both benign and malignant).

Age Group (years)	Benign	(%)	Malignant	(%)	Total
1-10	11	7.9	01	0.71	12
11-20	21	15.11	02	1.44	23
21-30	14	10.1	03	2.1	17
31-40	13	9.4	11	7.9	24
41-50	06	4.3	07	05	13
51-60	06	4.3	14	10.1	20
61-70	01	0.71	18	13	19
71-80	01	0.71	08	5.8	9
81-90	01	0.71	01	0.71	2
Total	74	53.24	65	46.76	139

Nevus (24.3%) was found to be the most common benign neoplastic neoplasm followed by hemangioma (21.6%) and dermoid (17.6%) respectively (Table 4).

Table 4

Prevalence of benign ophthalmic lesions

Benign Lesions	No Of Cases (n)	Percentage (%)
Nevus	18	24.3
Hemangioma	16	21.6
Dermoid Cyst	13	17.6
Lipodermoid	07	9.5
Papilloma	06	8.1
Benign cystic lesion	04	5.4
Verrucoid Keratosis	02	2.7
Fibroma	02	2.7
Adenoma	02	2.7
Ocular Melanocytois	01	1.35
Syringocystadenoma Papilliferum	01	1.35
Fibrous Histiocytoma	01	1.35
Lipoma	01	1.35
Total	74	100

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).

Table 5

Pattern of malignant ophthalmic lesions.

Malignant Lesions	No Of Cases (n)	Percentage (%)
Squamous Cell carcinoma	30	46.16
Conjunctival Intraepithelial Neoplasia (CIN)	07	10.76
Occular Surface Squamous Neoplasia (OSSN) with dysplasia	07	10.76
Sebaceous carcinoma	06	9.23
Lymphoproliferative Lesion	05	7.7
Basal Cell carcinoma	04	6.15
Melanoma	03	4.62
Carcinoma-Undifferentiated Basal Cell carcinoma	02	3.07
Retinoblastoma	01	1.53
Total	65	100

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).

Table 6

Locations of the lesions with regard to number of patients.

Location	No of cases (n)	Percentage (%)
Conjunctiva and Cornea	52	37.41
Eyelid	50	35.97
Limbus	16	11.51
Canthal	09	6.47
Not Specified	04	2.88
Intraocular	03	2.16
Orbit	03	2.16
Lacrimal Gland	02	1.44
Total	139	100

DISCUSSION

Among 251 samples, the prevalence of ophthalmic neoplastic lesion were 139 (55.37%). Among these, 74 (53.24%) were benign and 65 (46.76%) were malignant tumors. Study carried out by Ud-Din N et al[3] showed the prevalence of 61.5% benign and 38.5% malignant ophthalmic neoplastic lesions. Shaikh IY et al[4] study showed the prevalence of 52.33% and 47.67% respectively. But there was a significant difference in prevalence of benign and malignant ophthalmic lesions when compared with study done by Bastola PS et al.[5]

Studies have shown that the accuracy of clinical diagnosis range from 50.8% to 96.0 % hence denoting the poor reliability.[1] The role of histopathology is the most important factor for diagnosis and management of the patient.[4] A variation in histological spectrum exists among itself on the basis of pattern and its likelihood of invading surrounding structures – which usually determines the prognosis.[6] Studies carried out in various tertiary eye hospitals in Nepal, previously have denoted that 3 in 10 ophthalmological samples sent to pathologists were determined to be malignant.[7]

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 (21.6%). Shaikh IY et al. (2011) from the similar study have reported the most common benign lesion being hemangioma (46%) followed by nevus (14.1%). Likewise, the most common malignant lesion in their study was squamous cell carcinoma (28.2%).[4] This result is comparable to our study, where the most common malignant lesions were also found to be squamous cell carcinoma (46.16%). Similarly, the Bastola PS et al. (2013)[5] study also showed the squamous cell carcinoma (22.5 %) as a most common malignant ophthalmic neoplasms in their study.

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.