EXTRAOCULAR EXTENSION OF CILIOCHOROIDAL MELANOMA AFTER TRANSSCLERAL FINE-NEEDLE ASPIRATION BIOPSY

To describe development of extraocular extension of ciliochoroidal melanoma after transscleral fine-needle aspiration biopsy (FNAB) for cytogenetic studies.

Transscleral FNAB was performed for cytogenetic analysis of melanoma using a long 27-gauge needle attached to a 10-mL syringe by connector tubing entering obliquely through the sclera overlying the tumor base. An iodine 125 radioactive plaque was immediately applied to the sclera over the tumor and biopsy site after FNAB.

One patient with large ciliochoroidal melanoma of the right eye.

Cytogenetic analysis of the melanoma revealed monosomy of chromosome 3. On examination, 18 months after plaque radiotherapy, there was regression of the tumor; however, a few small subepithelial pigmented lesions were noted in the conjunctiva close to the FNAB site. Excisional biopsy of the conjunctival pigmented lesions with 3 mm margins and with supplemental cryotherapy to the surrounding conjunctival margins and to the underlying sclera was performed. Histopathologic evaluation showed an oval nodule composed of a mixture of spindle and epithelioid cells deep within the substantia propria consistent with extraocular extension of uveal melanoma. Magnetic resonance imaging of the orbits showed no evidence of orbital involvement. This is the only case of extraocular extension developing among 408 consecutive transscleral biopsies (0.2%) performed at our center for cytogenetic or cytopathologic analysis.

Although rare, transscleral FNAB of ciliochoroidal melanoma can lead to extraocular extension of the tumor through the biopsy site. Possible techniques to reduce the risk of this problem are discussed.