Background: We compared the immunoglobulin (IG) heavy chain (IGH) leader and FR1 primer sets to measure clone sizes and detect immunoglobulin heavy chain variable (IGHV) region somatic hypermutations (SHMs) in Korean patients with chronic lymphocytic leukemia (CLL). We also analyzed IGH and immunoglobulin kappa (IGK) to identify Korean-specific IGs in CLL. Methods: Next-generation sequencing (NGS)–based gene rearrangements and IGHV SHMs were assessed in 40 patients using IGH leader, IGH FR1, and IGK primers. Flow cytometry, karyotyping, interphase FISH, and NGS-based variant analyses were performed for 165 genes. Results: Clonal IGH and IGK rearrangements were detected in 100.0% and 97.5% of patients, respectively. Clonal size was generally smaller per NGS than per flow cytometry, particularly when using the IGH leader (median: 52.5%) versus the IGH FR1 primer set (73.2%). IGHV SHMs occurred in approximately 70% of patients; 10% showed primer set discrepancies. The incidence of IGHV SHMs was low in patients at high risk (i.e., with TP53 abnormalities; complex karyotypes; and ATM, NOTCH1, SF3B1, or BIRC3 variants). IGHV3 was the most common IGHV (58.3%), and IGHV4-34 was most frequently identified (14.6%). IGHV1 and IGHV1-69 usage differed significantly between Koreans and westerners. IGHJ4 was the most common IGHJ (56.3%). A single IGKV–IGKJ gene rearrangement was most frequently observed (18.9%), whereas intron-KDE was the most common rearrangement (30.6%). Conclusions NGS may underestimate CLL clonal size, particularly when using the IGH leader primer set. IGHV SHMs were inversely associated with negative prognostic factors.Our data suggest ethnic differences in CLL pathogenesis.

Background/Aims: Cold snare polypectomy (CSP) is recommended for colorectal polyps <10 mm; however, the impact of snare size on clinical outcomes remains unclear. This study evaluated the efficacy and safety of 10-mm and 15-mm snares for CSP of small colorectal polyps. Methods: In this prospective multicenter study, patients with 4–10 mm non-pedunculated polyps underwent CSP with either a 10-mm or 15-mm snare. Both snares had identical wire thickness and hexagonal loop design. The primary outcome was histological complete resection rate (CRR). Secondary outcomes included adverse events and technical parameters. Results: In total, 182 patients were enrolled (10-mm group: n = 92; 15-mm group: n = 90). Baseline characteristics, including age, sex, polyp size, morphology, location, and pathology, were comparable between groups. Histological CRRs were 90.2% in the 10-mm group and 91.1% in the 15-mm group (P= 0.483). No significant differences were observed in the presence of submucosal tissue within specimens (P= 0.523), iatrogenic ulcer size (P= 0.532), hematoma occurrence (P= 0.391), or intraprocedural bleeding requiring hemostasis (6.5% vs. 5.6%; P= 0.974). No cases of delayed bleeding or perforation were reported. Logistic regression analysis identified iatrogenic ulcer size > 8 mm as an independent predictor of complete resection (odds ratio, 3.89; 95% confidence interval, 1.15–13.21; P= 0.029); snare size was not significantly associated with CRR (P= 0.519). Conclusions CSP using either a 10-mm or a 15-mm snare for 4–10 mm non-pedunculated colorectal polyps showed no significant difference in complete resection or safety outcomes within this size range. (Clinical Research Information Service [CRIS], KCT0005031)

Background: Light-chain amyloidosis (AL) is the most common form of systemic amyloidosis. This study aimed to evaluate the usefulness of laboratory tests for light-chain clonality and bone marrow (BM) findings in AL amyloidosis. Methods: We retrospectively enrolled patients newly diagnosed with AL amyloidosis on pathological examination who underwent a BM biopsy. Laboratory test data for light-chain clonality were collected and compared. Amyloid deposits were identified with H&E, Congo red, and PAS stains. Results: We reviewed 98 patients with AL amyloidosis. Light chain clonality (λ, 64 cases; κ, 34 cases) was detected by serum immunofixation electrophoresis (IFE) (63.3%), urine IFE (70.8%), serum protein electrophoresis (PEP) (44.9%), urine PEP (44.8%), serum free light chain (SFLC) ratio (79.5%), and BM immunohistochemistry (IHC) (85.7%). Flow cytometric (FCM) assay identified aberrant BM plasma cells in 92.9% of cases. BM amyloid deposits were identified in 35 of the 98 cases (35.7%); 71.4% (25/35) were Congo red-positive, and 100.0% (35/35) were PAS-positive. Conclusion Laboratory tests for detecting light-chain clonality in AL amyloidosis in order of sensitivity include FCM assay for aberrant plasma cells, IHC for light chains on BM biopsy or clot section, SFLC ratio, and serum and urine IFE. Congo red staining of BM samples remains an important tool for identifying amyloid deposits in BM. Periodic acid-Schiff (PAS) staining can be useful in diagnosing some cases of Congo red-negative amyloidosis.

No abstract available.
B-Lymphocytes* ; Bone Marrow* ; Humans ; Lymphoma, B-Cell* ; Lymphoma, T-Cell* ; T-Lymphocytes*