TABLE 1.
Clinicopathologic characteristics of pediatric LCH study cohort (n = 26)
| IHC/MOL Concordance | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Sample | Age/Gender | Clinical Classification | LCH,% of section | Specimen | Decal | VE1 0–3+ | VE1 0%–100% | AS-qPCR | Lenient IHC(≥1+, ≥1%) | Stringent IHC(≥2+, ≥10%) |
| LCH-51 | 11/M | MS-LCH | 40 | Bone | Yes | 0+ | 0 | NEG | NEG | NEG |
| LCH-31 | 1/F | SS-LCH | 80 | Bone | Yes | 0+ | 0 | NEG* | NEG | NEG |
| LCH-55 | 10/M | SS-LCH | 30 | Bone | Yes | 1+ | 10 | NEG* | POS-FP | NEG |
| LCH-6 | 11/M | SS-LCH | 5 | Bone | Yes | 1+ | 50 | NEG | POS-FP | NEG |
| LCH-16 | 2/M | MS-LCH | 95 | Bone | No | 1+ | 70 | NEG | POS-FP | NEG |
| LCH-32 | 3/M | SS-LCH | 90 | Bone | No | 1+ | 80 | NEG | POS-FP | NEG |
| LCH-34 | 1/M | SS-LCH | 90 | Bone | No | 1+ | 30 | NEG | POS-FP | NEG |
| LCH-35 | 1/F | MS-LCH | 20 | Skin | No | 1+ | 60 | NEG | POS-FP | NEG |
| LCH-57 | 7 mo/F | MS-LCH | 70 | LN | No | 1+ | 70 | NEG | POS-FP | NEG |
| LCH-58 | 9 mo/F | SS-LCH | 50 | LN | No | 1+ | 90 | NEG | POS-FP | NEG |
| LCH-59 | 10/M | SS-LCH | 80 | Bone | No | 1+ | 70 | NEG | POS-FP | NEG |
| LCH-2 | 1/M | MS-LCH | <5 | Soft tissue | No | 1+ | 30 | POS | POS | NEG-FN |
| LCH-33 | 9 mo/M | MS-LCH | 30 | Bone | Yes | 1+ | 20 | POS | POS | NEG-FN |
| LCH-13 | 8/F | SS-LCH | <5 | Bone | Yes | 1+ | 50 | POS | POS | NEG-FN |
| LCH-53 | 4/M | SS-LCH | 25 | Bone | Yes | 2+ | 60 | POS | POS | POS |
| LCH-9 | 1/M | MS-LCH | 85 | LN | No | 2+ | 80 | POS | POS | POS |
| LCH-36 | 2/F | MS-LCH | 40 | Skin | No | 2+ | 50 | POS | POS | POS |
| LCH-47 | 2/F | MS-LCH | 70 | LN | No | 2+ | 90 | POS | POS | POS |
| LCH-3 | 9 mo/F | MS-LCH | 75 | Liver | No | 3+ | 40 | POS | POS | POS |
| LCH-5 | 2/F | MS-LCH | 70 | Soft tissue | No | 3+ | 80 | POS | POS | POS |
| LCH-7 | 11 mo/M | SS-LCH | 60 | Soft tissue | No | 3+ | 50 | POS | POS | POS |
| LCH-30 | 17/M | SS-LCH | 60 | Soft tissue | No | 3+ | 80 | POS | POS | POS |
| LCH-48 | 5/F | MS-LCH | 70 | LN | No | 3+ | 30 | POS | POS | POS |
| LCH-54 | 1/F | SS-LCH | 80 | Soft tissue | No | 3+ | 80 | POS | POS | POS |
| LCH-60 | 10/M | MS-LCH | 40 | Soft tissue | No | 3+ | 60 | POS | POS | POS |
| LCH-62 | 3/F | MS-LCH | 90 | Spleen | No | 3+ | 60 | POS | POS | POS |
The asterisks (*) denote decalcified samples that failed AS-qPCR in FFPE sections. Molecular results for these 2 specimens were obtained from nondecalcified sections from the same specimen.
Abbreviations: AS-qPCR, allele-specific real-time PCR; Decal, decalcification; F, female; FN, false-negative; FP, false-positive; IHC, immunohistochemistry; LCH, Langerhans cell histiocytosis; LN, lymph node; M, male; mo, month; MOL, molecular; MS-LCH, multisystem LCH; NEG, negative; POS, positive; SS-LCH, single system LCH.