Abstract
Purpose: :
The diagnosis of conjunctival intraepithelial neoplasia (CIN) is usually based on clinical appearance. The gold standard of treatment for CIN is excisional biopsy with adjunctive cryotherapy. Studies have shown topical agents such as interferon-alpha2b (IFNα2b) to be efficacious for treating CIN, but it is not clear exactly how long a patient should be treated with these agents in order to achieve adequate treatment and prevent tumor recurrence. The purpose of this study is to assess whether in vivo confocal microscopy (IVCM) can help distinguish CIN from benign lesions, and whether serial IVCM in patients treated with IFNα2b can confirm treatment efficacy and help monitor for recurrence.
Methods: :
This is a retrospective chart review of consecutive cases of suspected CIN treated with IFNα2b and imaged using the Heidelberg Retina Tomograph III - Rostock Cornea Module (Heidelberg, Germany) in vivo confocal microscope at the Veterans Affairs Boston Healthcare System. A healthy normal volunteer was included for comparison.
Results: :
Between January 2010 and July 2011, there were 9 cases in 9 patients of suspected CIN treated with topical IFNα2b. Two of the eyes were initially treated with topical IFNα2b, and subsequently underwent excisional biopsy due to unsatisfactory clinical response. One of these lesions proved to be squamous cell carcinoma, and the other lesion had histologic findings consistent with a severely inflamed pterygium. The remaining 7 cases resolved clinically after IFNα2b treatment. With IVCM, 7 of 9 presumed CIN lesions were initially seen to have cells with bright and prominent nuclei. In 7 of 9 cases, the cell borders were indistinct, in contrast to the usually distinct cell borders in normal conjunctival epithelium. After the CIN lesions were no longer apparent clinically, bright prominent nuclei could occasionally be seen by IVCM. In 5 cases followed with serial IVCM during IFNα2b treatment, the cell nuclei generally became less prominent and the cell borders more distinct and regular. In one case, there was complete resolution clinically and by IVCM by 4 months. The pterygium also had areas of bright nuclei and indistinct cell borders.
Conclusions: :
IVCM cannot replace the pathologic and clinical diagnosis of CIN, but can aid in monitoring patients for disease regression or recurrence. Also, treatment of CIN with IFNα2b alone can lead to complete clinical and microscopic resolution of disease.
Keywords: tumors • conjunctiva • imaging/image analysis: clinical