title: Ocular manifestation in myeloid/NK cell precursor acute leukemia: a case report. Diagnosed by flow cytometry and PCR from aqueous humor.
abstract: BACKGROUND
  Myeloid/NK cell precursor acute leukemia (MNKL) is a rare type of leukemia, and ocular complications have not previously been reported. We now report a patient with MNKL who developed intraocular infiltrates during follow-up.
  
  
  RESULTS
  A 13-year-old boy diagnosed with MNKL developed left eye pain 3 months after starting treatment. Examination of the left eye revealed a visual acuity of counting fingers at 20 cm, ciliary hyperemia, small corneal keratic precipitates, hypopyon, grade 4 vitreous opacities, and an obscured fundus. The differential diagnosis was between an opportunistic infection associated with immunodeficiency and an intraocular leukemic cell infiltrate. Therefore, a sample of aqueous humor was aspirated. Multiplex PCR/broad-range PCR of the aqueous humor was below detection limits for viruses, bacteria, and fungi. Flow cytometry (FCM) detected NK-related CD56-positive cells, thus leading to a diagnosis of ocular infiltrates due to MNKL. With treatment of the ocular infiltrates by consolidation systemic chemotherapy including intrathecal methotrexate (MTX), there was clearing of the vitreous opacities; and optic disc swelling, retinal hemorrhages, exudates, and protuberant lesions were now seen. With the addition of local radiation therapy to the eye, there was a dramatic treatment response, with regression of the optic disc findings and retinal lesions, and an improved visual acuity of 1.5.
  
  
  CONCLUSIONS
  We encountered the first case of MNKL in which ocular infiltrates developed during follow-up. Multiplex PCR and FCM of the aqueous humor were useful in rapidly distinguishing leukemic cell infiltrates from an opportunistic infection. This case highlights the usefulness of intrathecal MTX and local radiotherapy in treating ocular infiltrates in patients with MNKL.
authors.affiliation: Department of Ophthalmology & Visual Science, Graduate School of Medical and Dental Science Department of Pediatrics and Developmental Biology Children's Cancer Center, National Center for Child Health and Development, Tokyo, Japan Department of Radiation Therapeutics and Oncology, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Akaike
authors.forename: Koju
authors.initials: K
authors.lastname: Kamoi
authors.forename: Mari
authors.initials: M
authors.lastname: Tezuka
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tomizawa
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Yoshimura
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Takagi
authors.forename: Kyoko
authors.initials: K
authors.lastname: Ohno-Matsui
mesh_terms: D000293:Adolescent; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage; D001082:Aqueous Humor / Q000166:cytology; D019002:CD56 Antigen / Q000378:metabolism; D003937:Diagnosis, Differential; D005134:Eye Neoplasms / Q000556:secondary*; D005434:Flow Cytometry; D006801:Humans; D007694:Killer Cells, Natural / Q000378:metabolism / Q000473:pathology*; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis* / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy; D008297:Male; D008727:Methotrexate / Q000008:administration & dosage; D016133:Polymerase Chain Reaction
chemical_list: D000964:Antimetabolites, Antineoplastic; D019002:CD56 Antigen; C522918:NCAM1 protein, human; D008727:Methotrexate