Small choroidal melanoma with chromosome 3 monosomy on fine-needle aspiration biopsy.
OBJECTIVE
To evaluate the presence of chromosome 3 monosomy in small choroidal melanoma using fine-needle aspiration biopsy (FNAB).


METHODS
Noncomparative case series.


METHODS
Fifty-six patients with small choroidal melanoma measuring 3 mm or less in thickness who were undergoing plaque radiotherapy.


METHODS
Fine-needle aspiration biopsy was used at the time of plaque radiotherapy to sample tumor cells using a 27-gauge long needle via an indirect transvitreal approach into the tumor apex for postequatorial tumors or a 30-gauge short needle via a direct transscleral approach into the tumor base for preequatorial tumors.


METHODS
Chromosome 3 monosomy in small choroidal melanoma.


RESULTS
The median tumor thickness was 2.6 mm. Monosomy 3 was found in 15 (27%) cases and disomy 3 was found in 32 (57%) cases. In 9 (16%) cases, genomic DNA yield was insufficient for genetic analysis. Fine-needle aspiration biopsy with a 27-gauge needle transvitreal approach provided quantity sufficient for genetic testing in 31 (97%) of 32 cases versus 16 (67%) of 24 cases sampled with a 30-gauge transscleral technique. Compared with disomy 3 tumors, monosomy 3 tumors were statistically more likely to occur in older patients (P = 0.040). Monosomy 3 (versus disomy 3) tumors showed thickness of more than 2 mm in 100% (vs. 84%), subretinal fluid in 87% (vs. 94%), symptoms in 40% (vs. 56%), orange pigment in 93% (vs. 81%), and margin of 3 mm or less to the optic disc in 20% (vs. 50%). There was no statistical difference between monosomy 3 and disomy 3 tumors in the presence or number of these clinical factors. However, small choroidal melanomas with monosomy 3 mutation were more likely to have had documented growth (63%) compared with those with disomy 3 (25%; P = 0.025; odds ratio, 5.00).


CONCLUSIONS
Using FNAB at the time of plaque radiotherapy, monosomy 3 was found in approximately 27% of small choroidal melanomas, more often in older patients and tumors with documented growth. Transvitreal biopsy into the tumor apex provided better yield compared with transscleral biopsy into the tumor base.
Shields
Carol L
CL
Ocular Oncology Service, Wills Eye Institute, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA. carol.shields@shieldsoncology.com
Materin
Miguel A
MA
Teixeira
Luiz
L
Mashayekhi
Arman
A
Ganguly
Arupa
A
Shields
Jerry A
JA
D001707:Biopsy, Needle / Q000379:methods; D002830:Choroid Neoplasms / Q000235:genetics* / Q000473:pathology; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics*; D004273:DNA, Neoplasm / Q000032:analysis; D005821:Genetic Techniques; D006801:Humans; D008545:Melanoma / Q000235:genetics* / Q000473:pathology; D018895:Microsatellite Repeats; D008875:Middle Aged; D009006:Monosomy / Q000235:genetics*; D012307:Risk Factors
D004273:DNA, Neoplasm