Staging of Ciliary Body and Choroidal Melanomas Based on Anatomic Extent

Abstract

Purpose To refine the anatomic classification and staging of ciliary body and choroidal melanomas in the TNM classification. Patients and Methods Tumor largest basal diameter and thickness of 7,369 patients were analyzed based on registry data from five ocular oncology centers. T categories were derived empirically by dividing data into blocks representing 3- × 3-mm fractions. Blocks with similar survival were grouped together so that no T category comprised a large majority of tumors, and each was uniform in survival, using randomly drawn 60% building and 40% validation data sets. Presence of ciliary body involvement (CBI) and extraocular extension (EXE) was analyzed among 5,403 patients to define T subcategories. Stages were generated by iteratively combining subcategories with similar survival. Results Of the 7,369 tumors analyzed, 24% were classified as T1, 33% as T2, 31% as T3, and 12% as T4. Ten-year Kaplan-Meier survival estimates for the T categories were 89%, 77%, 58%, and 39%, respectively (P < .001). Survival of patients in four subcategories based on presence or absence of CBI and EXE differed significantly within each T category (P = .018 for T1; P < .001 for T2 to T4). EXE exceeding 5 mm in largest diameter carried a worse prognosis than smaller extensions (P < .001) and was assigned a separate subcategory. Ten-year Kaplan-Meier survival estimates for stages I, IIA to IIB, and IIIA to IIIC were 88%, 80%, 67%, 45%, 27%, 10%, respectively (P < .001). Conclusion This evidence-based anatomic classification provides a basis for staging ciliary body and choroidal melanomas in the seventh edition of the Cancer Staging Manual of the American Joint Committee on Cancer.

Small Choroidal Melanoma Revealed by a Large Extrascleral Extension

“…In most cases, choroidal melanomas are confined within the scleral envelope. Extraocular extension is present at the time of diagnosis in only 3-5.8% of the patients with uveal melanoma [2,3,4]. It is more common in medium or large size tumors and in tumors located in the ciliary body, at the site of vortex veins and in the juxtapapillary area.…”

Comparison of Alternative Tumor Size Classifications for Posterior Uveal Melanomas

“…31,32 This staging system took into account the size of the primary tumor (T), presence of lymph node involvement (N), presence of distant metastasis (M), and the presence of extrascleral tumor extension. The 2002 TNM system for malignant uveal melanoma defined small (T1) tumors as 10 mm in LBD and 2.5 mm in TH, large (T3) tumors as >16 mm in LBD or >10 mm in TH, and medium (T2) tumors as intermediate in size.…”

The Prognostic Value of AJCC Staging in Uveal Melanoma Is Enhanced by Adding Chromosome 3 and 8q Status

“…5 The current seventh edition of the AJCC staging uses tumor size, ciliary body involvement, and extraocular growth as its parameters for prognostication in UM. 6,7 Although the AJCC staging system for UM is an internationally recognized and validated method to estimate patient survival, it is currently based only on the anatomic extent of the tumor and does not take genetic data into account. [8][9][10] Concurrent to the development and refinement of the classical AJCC staging system, translational research has led to more insight into the genetics of UM.…”