Original article 375 Digital surface microscopy analysis of conjunctival pigmented lesions: a preliminary study Gian Marco Tosi a , Pietro Rubegni b , Karin Schuerfeld c , Paolo Toti c , Gabriele Cevenini d , Giordana Dell’Eva e , Lucio Andreassi b , Aldo Caporossi a and Marco Burroni b The objective of this study was to investigate whether digital surface microscopy (DSM) could be used for the follow-up and comparison of malignant and benign con- junctival pigmented lesions (CPLs). Thirty-nine CPLs [16 de novo malignant melanomas (MMs), one MM arising from primary acquired melanosis (PAM), six PAMs and 16 naevi] were digitally analysed and biopsied. All of the PAMs and 10 naevi, which had not been surgically excised, were followed up using DSM. Thirty parameters were evaluated grouped into four categories: geometry, colour, texture and islands of colour. None of the CPLs that were followed up, which comprised 10 naevocytic naevi and seven PAMs, showed any morphological change at DSM analysis, except for one PAM which developed an MM 1 year later. Of the geometric variables examined, the area, maximum dia- meter and minimum diameter showed significantly higher values in MMs compared with benign CPLs. With regard to the colour of CPLs, MMs were significantly darker and bluer than naevi. In the texture group, contrast was significantly higher in MMs. In the islands-of-colour group, the imbal- ance of blue–grey regions and the presence of dark areas were significantly higher in MMs. DSM greatly simplified the follow-up of CPLs, such as PAMs with atypia, by providing satisfactory quality images with high reproduci- bility; this technique is also easy to use and well accepted by patients. Moreover, this preliminary study allowed us to determine which objective variables could be important for distinguishing between benign CPLs and conjunctival MMs. Melanoma Res 14:375–380 c 2004 Lippincott Williams & Wilkins. Melanoma Research 2004, 14:375–380 Keywords: Computer, conjunctival melanoma, conjunctival naevus, image analysis, primary acquired melanosis a Department of Ophthalmology and Neurosurgery, b Dermatology, c Human Pathology and Oncology, d Thoracic Surgery and Biomedical Technologies, University of Siena, Siena, Italy and e Lega Italiana Tumori Siena, Siena, Italy. Sponsorship: This work was supported by a grant from the Italian Ministry of Instruction, University and Research. Correspondence and requests for reprints to Dr Pietro Rubegni, Dipartimento di Dermatologia, Universita` di Siena, Via delle Scotte, 1, 53100 Siena, Italy. Tel: + 39 0577585422; fax: + 39 057744238; e-mail: rubegni@unisi.it Received 29 April 2004 Accepted (after revision) 24 June 2004 Introduction Conjunctival malignant melanoma (MM) is a rare malignancy with an estimated incidence of 0.02–0.08 per 100 000 inhabitants in Western populations [1]. The incidence of conjunctival melanoma in the white popula- tion has increased in a similar manner to cutaneous melanoma and, from a biological point of view, shows a greater resemblance to its cutaneous counterpart than its uveal counterpart [1,2]. Three clinical and histopatholo- gical forms of conjunctival MM have been identified: MM evolving from primary acquired melanosis (PAM), MM with no pre-existing conjunctival pigmented lesions (CPLs) and MM originating from a conjunctival naevus [3,4]. Conjunctival MM is a potentially deadly tumour. Metastases are detected in 14–27% of patients [5–7] and mortality is 13–40% over 10 years [6–8]. According to some authors [9], it should be managed, like all conjunctival malignancies, with meticulous surgical plan- ning using a wide microsurgical dissection, avoiding incisional biopsy because of the subsequent risk of tumour dissemination and recurrence. Early diagnosis is of crucial importance in reducing mortality and avoiding disfiguring surgery, which becomes mandatory at a later stage. In dermatology, a recent technique known as epilumines- cence light microscopy (ELM), which magnifies lesions and enables them to be examined down to the dermo- epidermal junction, has led to a 5–30% increase in diagnostic accuracy with respect to simple clinical observation [10,11]. However, evaluation of the many morphological characteristics of pigmented lesions by ELM is often extremely complex and subjective. To avoid these problems, technologies and methods have been developed to enable an objective evaluation to be made of the many parameters that have emerged with decades of experience of using ELM [12]. An example is digital surface microscopy (DSM), which gathers numerical data and allows pigmented lesion images to be described objectively [13–16]. In fact, DSM is a recent evolution of 0960-8931 c 2004 Lippincott Williams & Wilkins Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.