title: Diagnosing ocular surface squamous neoplasia in East Africa: case-control study of clinical and in vivo confocal microscopy assessment.
abstract: OBJECTIVE
  To examine the reliability of clinical examination and in vivo confocal microscopy (IVCM) in distinguishing ocular surface squamous neoplasia (OSSN) from benign conjunctival lesions.
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  Sixty individuals with conjunctival lesions (OSSN and benign) and 60 age-matched controls with normal conjunctiva presenting to Kilimanjaro Christian Medical Centre, Moshi, Tanzania.
  
  
  METHODS
  Participants were examined and photographed, and IVCM was performed. Patients with conjunctival lesions were offered excisional biopsy with histopathology and a human immunodeficiency virus (HIV) test. The IVCM images were read masked to the clinical appearance and pathology results. Images were graded for several specific features and given an overall categorization (normal, benign, or malignant). A group of 8 ophthalmologists were shown photographs of conjunctival lesions and asked to independently classify as OSSN or benign.
  
  
  METHODS
  Comparison of the histopathology diagnosis with the clinical and IVCM diagnosis.
  
  
  RESULTS
  Fifty-two cases underwent excisional biopsy with histopathology; 34 were on the OSSN spectrum, 17 were benign, and 1 was lymphoma. The cases and controls had comparable demographic profiles. Human immunodeficiency syndrome infection was more common in OSSN compared with benign cases (58.8% vs. 5.6%; odds ratio, 24.3, 95% confidence interval [CI], 2.8-204; P = 0.003). Clinically, OSSN lesions more frequently exhibited feeder vessels and tended to have more leukoplakia and a gelatinous appearance. Overall, the ophthalmologists showed moderate agreement with the histology result (average kappa = 0.51; 95% CI, 0.36-0.64). The masked grading of IVCM images reliably distinguished normal conjunctiva. However, IVCM was unable to reliably distinguish between benign lesions and OSSN because of an overlap in their appearance (kappa = 0.44; 95% CI, 0.32-0.57). No single feature was significantly more frequent in OSSN compared with benign lesions. The sensitivity and specificity of IVCM for distinguishing OSSN from benign conjunctival lesions were 38.5% and 66.7%, respectively.
  
  
  CONCLUSIONS
  In East Africa, conjunctival pathology is relatively common and can present significant diagnostic challenges for the clinician. In this study, neither clinical examination nor IVCM was found to reliably distinguish OSSN from benign conjunctival pathology because of an overlap in the features of these groups. Therefore, IVCM cannot currently replace histopathology, and management decisions should continue to rely on careful clinical assessment supported by histopathology as indicated.
authors: Department of Ophthalmology, Kilimanjaro Christian Medical Centre, Moshi, Tanzania.
authors: Marie B
authors: MB
authors: Nguena
authors: Department of Pathology, University Medical Centre, Utrecht, The Netherlands.
authors: Jan G
authors: JG
authors: van den Tweel
authors: Department of Ophthalmology, Kilimanjaro Christian Medical Centre, Moshi, Tanzania.
authors: William
authors: W
authors: Makupa
authors: Department of Ophthalmology, Kilimanjaro Christian Medical Centre, Moshi, Tanzania; International Centre for Eye Health, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom.
authors: Victor H
authors: VH
authors: Hu
authors: Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors: Helen A
authors: HA
authors: Weiss
authors: International Centre for Eye Health, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom; Department of Ophthalmology, University of Nairobi, Nairobi, Kenya.
authors: Stephen
authors: S
authors: Gichuhi
authors: Department of Ophthalmology, Kilimanjaro Christian Medical Centre, Moshi, Tanzania; International Centre for Eye Health, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom. Electronic address: matthew.burton@lshtm.ac.uk.
authors: Matthew J
authors: MJ
authors: Burton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002278:Carcinoma in Situ / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D016022:Case-Control Studies; D003230:Conjunctival Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D015828:Eye Infections, Viral / Q000175:diagnosis / Q000453:epidemiology; D005260:Female; D015658:HIV Infections / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013636:Tanzania / Q000453:epidemiology; D055815:Young Adult