CD19 chimeric antigen receptor T-cell (CAR-T) therapy, a genetically engineered cell therapy, showed unprecedented efficacy in the treatment of relapsed or refractory diffuse large B-cell lymphoma. Two agents, axicabtagene ciloleucel and tisagenlecleucel, were approved by the Food and Drug Administration in 2017. However, CAR-T therapy is a treatment with complex logistics and high costs, as well as inherent adverse events, including cytokine-release syndrome and neurotoxicity. In addition, predictive biomarkers for efficacy and toxicity are lacking. Industry-academy cooperation is urgently required to develop CAR-T therapy that is effective, safe, and affordable for patients in Korea.
B-Lymphocytes ; Biomarkers ; Cell- and Tissue-Based Therapy ; Humans ; Korea ; Lymphoma, B-Cell ; Lymphoma, Large B-Cell, Diffuse ; Organization and Administration ; Receptors, Antigen ; T-Lymphocytes ; United States Food and Drug Administration

CD19 chimeric antigen receptor T-cell (CAR-T) therapy, a genetically engineered cell therapy, showed unprecedented efficacy in the treatment of relapsed or refractory diffuse large B-cell lymphoma. Two agents, axicabtagene ciloleucel and tisagenlecleucel, were approved by the Food and Drug Administration in 2017. However, CAR-T therapy is a treatment with complex logistics and high costs, as well as inherent adverse events, including cytokine-release syndrome and neurotoxicity. In addition, predictive biomarkers for efficacy and toxicity are lacking. Industry-academy cooperation is urgently required to develop CAR-T therapy that is effective, safe, and affordable for patients in Korea.

BACKGROUND: Clostridium difficile infection (CDI) has markedly risen and is associated with hypervirulent ribotype 027 outbreaks in North America and Europe since 2003. The aims of this study were to determine the prevalence of ribotype 027 among C. difficile isolates in Korea, to characterize the ribotype 027 isolates, and to determine the clinical severity of CDI in patients infected with these isolates. METHODS: A total of 1,251 isolates of C. difficile recovered from stool specimens of suspected CDI patients at two tertiary-care hospitals and one commercial laboratory between 2002 and 2009. Genes for toxin A (tcdA), toxin B (tcdB), and binary toxin (cdtA and cdtB) were detected by PCR. Mutation in the tcdC gene was detected by sequencing after PCR amplification. For molecular genotyping, we performed PCR-ribotyping, pulsed-field gel electrophoresis (PFGE), and multilocus variable-number tandem-repeat analysis (MLVA). Minimum inhibitory concentrations of moxifloxacin were determined using Etest strips (AB bioMerieux, Sweden). RESULTS: We identified 7 isolates as ribotype 027. These isolates had the same tcdC mutation as the epidemic strain, and 6 of them were resistant to moxifloxacin. The isolates were categorized into 3 different PFGE types and 7 different MLVA types. All the 7 cases had occurred sporadically. CONCLUSIONS: C. difficile ribotype 027 is uncommon, but it has emerged in Korea. The spread of this ribotype should be closely monitored in order to avoid an outbreak of CDI in Korea.
Adult ; Aged ; Aged, 80 and over ; Bacterial Proteins/genetics/metabolism ; Bacterial Toxins/genetics/metabolism ; Clostridium difficile/genetics/*isolation & purification ; Drug Resistance, Bacterial ; Electrophoresis, Gel, Pulsed-Field ; Enterocolitis, Pseudomembranous/microbiology ; Enterotoxins/genetics/metabolism ; Feces/microbiology ; Female ; Humans ; Male ; Microbial Sensitivity Tests ; Middle Aged ; Mutation ; Polymerase Chain Reaction ; Republic of Korea ; *Ribotyping

PURPOSE: The purpose of this study was to evaluate the contributions and limitations of the cervical cancer screening test with accuracy in Korea. METHODS: This was a retrospective observational study. The study population consisted of all participants who underwent cervical cancer screening test from 2009 to 2014. The data were obtained from National Health Information Database (NHID) which represents medical use records of most Koreans. As the indices for contributions and limitations of the screening test, crude detection rate, incidence rate of interval cancer, sensitivity, specificity, and positive predictive value were used. RESULTS: The crude detection rate of screening test per 100,000 participants increased from 100.7 in 2009 to 102.1 in 2014. The incidence rate of interval cancer per 100,000 negatives decreased from 13.0 in 2009 to 10.2 in 2014. The sensitivities of screening test were 88.7% in 2009 and 91.2% in 2014, and the specificities were 98.5% in 2009 and 97.7% in 2014. The positive predictive value of screening decreased from 6.2% in 2009 to 4.3% in 2014. CONCLUSIONS: The Korean national cervical cancer screening program has improved in accuracy and has contributed to detection of early stage of cervical cancer over the years. Along with efforts to promote participation in cancer screening programs, quality control over the screening program should be enhanced.
Carcinoma in Situ ; Early Detection of Cancer ; Incidence ; Korea* ; Mass Screening* ; Observational Study* ; Papanicolaou Test ; Quality Control ; Retrospective Studies* ; Sensitivity and Specificity ; Uterine Cervical Neoplasms*

PURPOSE: The prognosis of human epidermal growth factor receptor 2 (HER2)-positive breast cancer has markedly improved since the introduction of trastuzumab. We aimed to evaluate the association between stromal tumor-infiltrating lymphocyte (sTIL) or FcrR polymorphisms and survival among patients with metastatic HER2-positive breast cancer who were treated with trastuzumab. METHODS: A total of 56 women with recurrent or metastatic HER2-positive breast cancer who received the trastuzumab-taxane combination as first-line treatment were included in this retrospective analysis. The single-step multiplex allele-specific real-time polymerase chain reaction technique was employed for FcrR3A genotyping. sTILs were identified via immunohistochemical analysis of surgical (n=34, 60.7%) or biopsy specimens of metastatic lesions (n=22, 39.3%). RESULTS: We classified patients based on the sTIL level (≤10% [n=44] or >10% [n=12]); high sTIL counts were more commonly observed in patients with hormone receptor-negative tumors than in those with hormone receptor-positive tumors (34.8% vs. 12.1%, p=0.02). There was a significant association between high sTIL levels and longer progression-free survival in comparison to low sTIL levels (median, 28.4 months vs. 16.8 months; p=0.03). With regard to the FcrR3A-158 genotype, patients were classified into the Phenylalanine/Phenylalanine group (23 patients, 41.1%), Phenylalanine/Valine group (23 patients, 41,1%), or Valine/Valine group (10 patients, 17.9%); these classifications were not associated with clinical outcomes. CONCLUSION: High sTIL expression may be associated with better efficacy of trastuzumab-containing therapy in patients with metastatic HER2-positive breast cancer. However, this finding warrants further evaluation in the larger population.
Biopsy ; Breast Neoplasms* ; Breast* ; Classification ; Disease-Free Survival ; Female ; Genotype ; Humans ; Lymphocytes, Tumor-Infiltrating* ; Prognosis ; Real-Time Polymerase Chain Reaction ; Receptor, Epidermal Growth Factor ; Receptor, ErbB-2 ; Retrospective Studies ; Trastuzumab

Purpose: For liposarcoma (LPS), clinical course and proper treatment strategies have not been well-established. Recently, immune-checkpoint inhibitors have shown potential efficacy in LPS. We aimed to describe the clinical course of LPS and evaluate the clinical impact of programmed death-ligand 1 (PD-L1). Materials and Methods: We reviewed all consecutive patients (n=332) who underwent curative-intent surgery for localized LPS at Asan Medical Center between 1989 and 2017. PD-L1 testing was performed in well-differentiated and dedifferentiated LPS. Results: The median age was 56 years with males comprising 60.8%. Abdomen-pelvis (47.6%) and well-differentiated (37.7%) were the most frequent primary site and histologic subtype, respectively. During a median follow-up of 81.2 months, recurrence was observed in 135 (40.7%), and 86.7% (117/135) were loco-regional. Well-differentiated subtype (hazard ratio [HR], 0.38), abdomen-pelvis origin (HR, 2.43), tumor size larger than 5 cm (HR, 1.83), positive resection margin (HR, 2.58), and postoperative radiotherapy (HR, 0.36) were significantly related with recurrence-free survival as well as visceral involvement (HR, 1.84) and multifocality (HR, 3.79) in abdomen-pelvis LPS. PD-L1 was positive in 31.5% (23/73) and 51.3% (39/76) of well-differentiated and dedifferentiated LPS, respectively, but had no impact on survival outcomes. Conclusion Clinical course of LPS was heterogeneous according to histology and anatomic location. Clear resection margin was important to lower recurrence and postoperative radiotherapy might have additional benefit. A decent portion of well-differentiated and dedifferentiated LPS were positive for PD-L1, but its prognostic role was unclear. Further research is needed to determine clinical implications of PD-L1, especially for advanced-stage LPS with unmet needs for effective systemic treatment.

Purpose: This study aimed to evaluate the survivals of patients with metastatic or recurrent gastric cancer (MRGC) over a period of 16 years and to investigate the recent changes in chemotherapy patterns. Materials and Methods: A total of 5,384 patients who received chemotherapy for MRGC between 2000 and 2015 were analyzed. The analysis focused on a comparison of the first-line chemotherapy between four periods: 2000–2003 (period 1), 2004–2007 (period 2), 2008–2011 (period 3), and 2012–2015 (period 4). Results: There were 880 patients (16%) in period 1, 1,573 (29%) in period 2, 1,435 (27%) in period 3, and 1,496 (28%) in period 4. Cytotoxic doublet-based therapy was the most commonly used (78%) first-line chemotherapy, and the combination of trastuzumab and doublet chemotherapy was provided to 288 patients. The OS rates at 12 and 24 months were steadily improved as follows: 39.2% and 14.6% in period 1, 43.5% and 17.6% in period 2, 50.3% and 20.6% in period 3, and 51.7% and 24.1% in period 4, respectively (p < 0.001). Among the patients who received the doublet-based chemotherapy, the median OS of those who received trastuzumab was 18.0 months (95% CI, 15.5–20.6), while that of those who received other doublet therapies was 11.2 months (95% CI, 10.8–11.6). Conclusion The OS was improved over time with advancements in chemotherapy, particularly the introduction of the anti-HER2–targeted agent, which contributed to the increase in the number of long-term survivors and established the superiority of OS for the treatment of MRGC.

Purpose: This study aimed to evaluate the survivals of patients with metastatic or recurrent gastric cancer (MRGC) over a period of 16 years and to investigate the recent changes in chemotherapy patterns. Materials and Methods: A total of 5,384 patients who received chemotherapy for MRGC between 2000 and 2015 were analyzed. The analysis focused on a comparison of the first-line chemotherapy between four periods: 2000–2003 (period 1), 2004–2007 (period 2), 2008–2011 (period 3), and 2012–2015 (period 4). Results: There were 880 patients (16%) in period 1, 1,573 (29%) in period 2, 1,435 (27%) in period 3, and 1,496 (28%) in period 4. Cytotoxic doublet-based therapy was the most commonly used (78%) first-line chemotherapy, and the combination of trastuzumab and doublet chemotherapy was provided to 288 patients. The OS rates at 12 and 24 months were steadily improved as follows: 39.2% and 14.6% in period 1, 43.5% and 17.6% in period 2, 50.3% and 20.6% in period 3, and 51.7% and 24.1% in period 4, respectively (p < 0.001). Among the patients who received the doublet-based chemotherapy, the median OS of those who received trastuzumab was 18.0 months (95% CI, 15.5–20.6), while that of those who received other doublet therapies was 11.2 months (95% CI, 10.8–11.6). Conclusion The OS was improved over time with advancements in chemotherapy, particularly the introduction of the anti-HER2–targeted agent, which contributed to the increase in the number of long-term survivors and established the superiority of OS for the treatment of MRGC.

Purpose: Patient-derived tumor cells can be a powerful resource for studying pathophysiological mechanisms and developing robust strategies for precision medicine. However, establishing organoids from patient-derived cells is challenging because of limited access to tissue specimens. Therefore, we aimed to establish organoids from malignant ascites and pleural effusions. Materials and Methods: Ascitic or pleural fluid from pancreatic, gastric, and breast cancer patients was collected and concentrated to culture tumor cells ex vivo. Organoids were considered to be successfully cultured when maintained for five or more passages. Immunohistochemical staining was performed to compare the molecular features, and drug sensitivity was assayed to analyze the clinical responses of original patients. Results: We collected 70 fluid samples from 58 patients (pancreatic cancer, n=39; gastric cancer, n=21; and breast cancer, n=10). The overall success rate was 40%; however, it differed with types of malignancy, with pancreatic, gastric, and breast cancers showing 48.7%, 33.3%, and 20%, respectively. Cytopathological results significantly differed between successful and failed cases (p=0.014). Immunohistochemical staining of breast cancer organoids showed molecular features identical to those of tumor tissues. In drug sensitivity assays, pancreatic cancer organoids recapitulated the clinical responses of the original patients. Conclusion Tumor organoids established from malignant ascites or pleural effusion of pancreatic, gastric, and breast cancers reflect the molecular characteristics and drug sensitivity profiles. Our organoid platform could be used as a testbed for patients with pleural and peritoneal metastases to guide precision oncology and drug discovery.

Background: The interest in Clostridioides difficile infection (CDI) has increased, and the choice of assays became wider since the first national survey in Korea on CDI diagnosis in 2015. We conducted a survey of the domestic CDI assays with more varied questions to understand the current situation in Korea. Methods: In April 2018, about 50 questions on the current status of CDI assays and details on implementation and perceptions were written, and a survey questionnaire was administered to laboratory medicine specialists in 200 institutions. Results: One-hundred and fifty institutions responded to the questionnaire, of which 90 (60.0%) including one commercial laboratory, performed CDI assays. The toxin AB enzyme immunoassay (toxin AB EIA), nucleic acid amplification test (NAAT), and C. difficile culture, glutamate dehydrogenase assay, alone or in combination with other assays, were used in 75 (84.3%), 52 (58.4%), 35 (36.0%), and 23 (25.8%), respectively, and 65 (73.0%) institutions performed a combination of two or more assays. The sensitivity of toxin AB EIA was more negatively perceived, and that on specificity was more positively perceived. The perception of sensitivity and specificity of NAAT was mostly positive. Perception on the algorithm test projected it as useful but in need of countermeasures. Sixty-three (73.3%) institutions responded that they performed surveillance on CDI. Conclusion This study provides useful evidence on the current status of CDI laboratory diagnosis in Korea as well as on items that require improvement and is thought to aid in standardizing and improving the CDI laboratory diagnosis in Korea.