Identification of High-risk Cryptic CRLF2 Rearrangements in B-Cell Acute Lymphoblastic Leukemia Utilizing an FGFR3/IGH Dual-Color Dual-Fusion DNA Probe Set.

B-cell acute lymphoblastic leukemia (B-ALL) is the most common childhood malignancy with gene rearrangements involving the IGH locus occurring in ∼5% of cases. Fluorescence in situ hybridization (FISH) probes targeting the IGH locus are not included in the standard children's oncology group (COG) fluorescence in situ hybridization panel. At our institute, we incorporated the use of FGFR3/IGH dual-color dual-fusion DNA probes for confirmation of aneuploidy 4 and 14 in diagnostic B-ALL specimens. Subsequently we have identified 4 B-ALL cases with cryptic CRLF2-IGH translocations that would otherwise have gone undetected. Detection of genetic alterations in B-ALL, such as CRLF2 rearrangements, may enhance patient risk stratification and therapy options in pediatric B-ALL.

A single center's approach to discriminating donor versus host origin of renal neoplasia in the allograft kidney.

Renal cell carcinoma (RCC) in the allograft of kidney transplant recipient (KTR) patients is rare and may represent a de novo process arising from the transplanted organ or metastasis from a clinically undetectable host primary. Determination of host versus donor origin is important for staging and management. We report our experience utilizing Penta-C (PC) and Penta-D (PD) short-tandem repeat (STR) microsatellite analysis to discriminate between host and donor origin of RCC identified in renal allografts. We identified 5 KTR patients with RCC in the allograft kidney. The PC and PD microsatellite analysis was applied to tumor, host, and donor formalin-fixed, paraffin-embedded tissue sections and/or fresh blood leukocytes to identify the origin of the neoplastic cells. The PC and PD microsatellite alleles were robustly amplified in all samples. Each case showed one or more informative alleles indicating that the neoplastic cells originate from donor tissue. Allele frequency data indicate that by using both PC and PD markers, we will be able to discriminate between host and donor cell of origin in over 99% of cases. The PC and PD microsatellite analysis is a convenient, robust, and efficient strategy to determine donor versus host origin or RCC in transplant kidney specimens.

Copper Transporter-CTR1 Expression and Pathological Outcomes in Platinum-treated Muscle-invasive Bladder Cancer Patients.

BACKGROUND/AIM: Platinum (Pt)-based neoadjuvant chemotherapy (NAC) is the standard-of-care for muscle-invasive bladder cancer (MIBC). However, the survival benefit with NAC is driven by patients with pathological response at cystectomy. Non-responders are subject to adverse effects of Pt, with delay in definitive treatment. Copper transporter receptor 1 (CTR1) plays an important role in Pt uptake and the level of expression may influence Pt sensitivity. We hypothesized that tumor CTR1 expression correlated with pathological outcome. PATIENTS AND METHODS: We identified matched paraffin-embedded tissues from pre-NAC transurethral bladder tumor resection (TURBT) and post-NAC radical cystectomy (RC) specimens in 47 patients with MIBC who received Pt-based NAC. Tumor and adjacent normal tissues were stained with CTR1 antibody. CTR1 expression was determined through immunohistochemistry by two pathologists blinded to the outcome (0=undetectable; 1+=barely detectable; 2+=moderate; and 3+=intense staining). Pathological response was defined as either down-staging to non-MIBC (≤pT1N0M0) or complete pathological response (pT0). Pathological outcome was compared between the CTR1 expression groups. RESULTS: Forty-three percent of TURBT and 41% of RC specimens expressed a CTR1 score of 3+. Forty-four percent of patients had a pathological response to NAC, and 17% had pT0 disease at cystectomy. In both pre-NAC TURBT and post-NAC RC specimens, a CTR1 expression score of 3+ correlated with pathological response (p=0.0076 and p=0.023, respectively). CONCLUSION: This is the first study to demonstrate a correlation between CTR1 tumor expression and pathological outcome in Pt-treated MIBC. These findings suggest that CTR1 expression may be a biomarker for Pt sensitivity.