A dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Master of Medicine in OphthalmologyOrbital exenteration is a surgical procedure used in the management of advanced malignant disease. It is used to treat both invasive and recurrent orbital tumours. This disfiguring surgical procedure involves removal of orbital contents, including the periorbita, eyelids and sometimes varying amounts of the surrounding peri-orbital skin. Studies from developing countries have shown that Squamous Cell Carcinoma (SCC) is the predominant indication for orbital exenteration. The high prevalence of conjunctival SCC in Sub-Saharan African has a strong link to ultraviolet radiation, Human Immunodeficiency Virus infection (HIV) and Human Papilloma Virus (HPV) infection. As the burden of disease increases, it becomes crucial for clinicians in Africa and other developing countries to understand how these Tumours’ behave, and how HIV potentially impacts on the disease. Such an evaluation may potentially benefit current management strategies. Furthermore, the need to effectively and appropriately manage such a neoplastic burden in a developing world setting with limited resources is of fundamental importance. This study reports an experience of orbital exenteration at this institution.
OBJECTIVES: Firstly to describe all orbital tumours exenterated at St. John Eye Hospital over a four year period in terms of histopathology, tumour behaviour and completeness of excision. Secondly to determine if a link to HIV infection exists.
DESIGN AND METHOD: A retrospective analysis of electronic records from the National Health Laboratory System (NHLS) was conducted on all the patients who underwent an orbital exenteration at St. John Eye Hospital from the 1st of July 2008 to 30th of June 2012
RESULTS: The total number of patients who underwent an orbital exenteration in the stated time period was 84. Twenty eight patients were excluded from the study and the final sample size was therefore 56.
The average age of presentation was 42 and the overall female to male ratio was 1:1.07. Four patients underwent a lid sparing procedure while the remaining 52 patients had a total exenteration. The tissue of origin was conjunctival in 75% of cases. The most frequent presenting complaint and indication for surgery was an invasive conjunctival tumour in 56% of patients, followed by a gross orbital tumour in 27% of patients. Squamous cell carcinoma of the conjunctiva was the most frequently diagnosed tumour. Out of 56 specimens, 51(91.06%) were of the squamous cell type, 1.79% High Grade Squamous Dysplasia, 3.57% Leiomyosarcoma, 1.79% Metastatic Breast Adenocarcinoma and 1.79% Spindle Cell Melanoma.
Histological grading of all specimens showed 69.64% of these tumours were moderately differentiated, 21.43% poorly differentiated and 8.93% were unknown.
The distribution of the tumour staging in the sample group, according to the TNM Classification was as follows, 51.79%- Stage 4, 19.64% -Stage 3, 10.71%-Stage 2, 1.79% Stage 1, 1.79% Stage Tumour In Situ and 14.28% unknown.
Regarding completeness of excision, 53.57% of tumours had positive tumour margins and 42.86% showed complete excision with clear margins, 3.57% were unknown. Only 28(50%) patients had a HIV result on electronic record. CD4 counts were available for 23 out of the 28 patients.MT201
