ABO Ocular Oncology 2 — Questions and Answers
Question 1: Which chromosomal abnormality in uveal melanoma is most strongly associated with metastatic risk?
- Monosomy 3 (Correct answer)
- Trisomy 8q
- Gain of 6p
- Loss of 1p
Correct answer: Monosomy 3
Monosomy 3 (loss of one copy of chromosome 3) is the single most significant prognostic cytogenetic marker in uveal melanoma, strongly associated with high metastatic risk.
Question 2: Primary intraocular lymphoma (PIOL) most commonly involves which ocular structures?
- Iris and anterior chamber
- Vitreous and subretinal space (Correct answer)
- Choroid and sclera
- Ciliary body and zonules
Correct answer: Vitreous and subretinal space
PIOL is typically a diffuse large B-cell lymphoma that most commonly involves the vitreous and subretinal space, often associated with CNS lymphoma.
Question 3: What is the hallmark CT finding of retinoblastoma in children?
- Hypodense mass with ring enhancement
- Isodense mass with cystic change
- Calcification within the intraocular mass (Correct answer)
- Homogeneous enhancement after contrast
Correct answer: Calcification within the intraocular mass
Calcification within the intraocular tumor is the hallmark CT finding of retinoblastoma, present in approximately 90-95% of cases and helpful in distinguishing it from other leukocoric conditions.
Question 4: Conjunctival melanoma most frequently arises from which precursor lesion?
- Conjunctival papilloma
- Primary acquired melanosis (PAM) with atypia (Correct answer)
- Conjunctival compound nevus
- Pinguecula
Correct answer: Primary acquired melanosis (PAM) with atypia
Conjunctival melanoma most commonly (75%) arises from primary acquired melanosis with atypia, which carries a significant risk of malignant transformation proportional to the degree of cytologic atypia.
Question 5: What is the most common orbital malignancy in adults?
- Cavernous hemangioma
- Lymphoma (Correct answer)
- Rhabdomyosarcoma
- Pleomorphic adenoma
Correct answer: Lymphoma
Lymphoma is the most common orbital malignancy in adults, typically presenting as a painless salmon-colored subconjunctival or orbital mass in older patients.
Question 6: Which funduscopic feature best distinguishes choroidal melanoma from choroidal metastasis?
- Orange lipofuscin pigment overlying the tumor (Correct answer)
- Subretinal fluid
- Posterior pole location
- Bilateral presentation
Correct answer: Orange lipofuscin pigment overlying the tumor
Orange lipofuscin pigment (lipofuscin deposits on the tumor surface seen by fluorescein angiography) is a classic feature of choroidal melanoma and is rarely seen overlying choroidal metastases.
Question 7: Orbital rhabdomyosarcoma in children most commonly presents at which age range?
- Under 2 years
- 5-10 years (Correct answer)
- 10-15 years
- 15-20 years
Correct answer: 5-10 years
Orbital rhabdomyosarcoma most commonly presents in children between ages 5-10 years (median age 7-8) with rapidly progressive unilateral proptosis.
ABO Ocular Oncology 2
Which chromosomal abnormality in uveal melanoma is most strongly associated with metastatic risk?