• Korean Journal of Radiology
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• v.21 no.7
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• pp.812-828
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• 2020

Objective: To provide an evidence-based guide for the MRI interpretation of complete tumor response after neoadjuvant chemoradiation therapy (CRT) for rectal cancer using visual assessment on T2-weighted imaging (T2) and diffusion-weighted imaging (DWI). Materials and Methods: PubMed MEDLINE, EMBASE, and Cochrane Library were searched on November 28, 2019 to identify articles on the following issues: 1) sensitivity and specificity of T2 or DWI for diagnosing pathologic complete response (pCR) and the criteria for MRI diagnosis; 2) MRI alone vs. MRI combined with other test(s) in sensitivity and specificity for pCR; and 3) tests to select patients for the watch-and-wait management. Eligible articles were selected according to meticulous criteria and were synthesized. Results: Of 1615 article candidates, 55 eligible articles (for all three issues combined) were identified. Combined T2 and DWI performed better than T2 alone, with a meta-analytic summary sensitivity of 0.62 (95% confidence interval [CI], 0.43-0.77; I² = 80.60) and summary specificity of 0.89 (95% CI, 0.80-0.94; I² = 92.61) for diagnosing pCR. The criteria for the complete response on T2 in most studies had the commonality of remarkable tumor decrease to the absence of mass-like or nodular intermediate signal, although somewhat varied, as follows: (near) normalization of the wall; regular, thin, hypointense scar in the luminal side with (near) normal-appearance or homogeneous intermediate signal in the underlying wall; and hypointense thickening of the wall. The criteria on DWI were the absence of a hyperintense signal at high b-value (≥ 800 sec/mm²) in most studies. The specific algorithm to combine T2 and DWI was obscure in half of the studies. MRI combined with endoscopy was the most utilized means to select patients for the watch-and-wait management despite a lack of strong evidence to guide and support a multi-test approach. Conclusion: This systematic review and meta-analysis provide an evidence-based practical guide for MRI assessment of complete tumor response after CRT for rectal cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1339-1344
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• 2014

Aims: Alterations in mitochondrial DNA (mtDNA) have been implicated in carcinogenesis and tumor progression. We here evaluated the diagnostic and prognostic potential of mtDNA as a biomarker for breast cancer. Methods: Using multiplex real-time polymerase chain reaction, nuclear DNA (nDNA) and mtDNA levels in serum, buffy coat, tumor, and tumor-adjacent tissue samples from 50 breast cancer patients were determined and assessed for associations with clinicopathological features. To evaluate mtDNA as a biomarker for distinguishing between the four sample types, we created receiver operating characteristic (ROC) curves. Results: The mtDNA levels in buffy coat were significantly lower than in other sample types. Relative to tumor-adjacent tissue, reduced levels of mtDNA were identified in buffy coat and tumor tissue but not in serum. According to ROC curve analysis, mtDNA levels could be used to distinguish between buffy coat and tumor-adjacent tissue samples with good sensitivity (77%) and specificity (83%). Moreover, mtDNA levels in serum and tumor tissue were positively associated with cancer TMN stage. Conclusions: The mtDNA levels in blood samples may represent a promising, non-invasive biomarker in breast cancer patients. Additional, large-scale validation studies are required to establish the potential use of mtDNA levels in the early diagnosis and monitoring of breast cancer.

• Brain Tumor Research and Treatment
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• v.6 no.2
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• pp.47-53
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• 2018

Brain tumors represent a diverse spectrum of histology, biology, prognosis, and treatment options. Although MRI remains the gold standard for morphological tumor characterization, positron emission tomography (PET) can play a critical role in evaluating disease status. This article focuses on the use of PET with radiolabeled glucose and amino acid analogs to aid in the diagnosis of tumors and differentiate between recurrent tumors and radiation necrosis. The most widely used tracer is $^{18}F$-fluorodeoxyglucose (FDG). Although the intensity of FDG uptake is clearly associated with tumor grade, the exact role of FDG PET imaging remains debatable. Additionally, high uptake of FDG in normal grey matter limits its use in some low-grade tumors that may not be visualized. Because of their potential to overcome the limitation of FDG PET of brain tumors, $^{11}C$-methionine and $^{18}F$-3,4-dihydroxyphenylalanine (FDOPA) have been proposed. Low accumulation of amino acid tracers in normal brains allows the detection of low-grade gliomas and facilitates more precise tumor delineation. These amino acid tracers have higher sensitivity and specificity for detecting brain tumors and differentiating recurrent tumors from post-therapeutic changes. FDG and amino acid tracers may be complementary, and both may be required for assessment of an individual patient. Additional tracers for brain tumor imaging are currently under development. Combinations of different tracers might provide more in-depth information about tumor characteristics, and current limitations may thus be overcome in the near future. PET with various tracers including FDG, $^{11}C$-methionine, and FDOPA has improved the management of patients with brain tumors. To evaluate the exact value of PET, however, additional prospective large sample studies are needed.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5427-5432
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• 2012

Background and Purpose: Ovarian cancer is the leading cause of death among gynecologic cancers because of the lack of effective early detection methods. Accuracies of the human epididymis protein 4 (HE4) and mesothelin in detecting ovarian cancer have never been systematically assessed. The current systematic review aimed to tackle this issue. Methods: MEDLINE, EMBASE, and Cochrane databases were searched (September 1995-November 2011) for studies on the diagnostic performances of HE4 and mesothelin in differentiating ovarian cancer from other benign gynecologic diseases. QUADAS items were used to evaluate the qualities of the studies. Meta-DiSc software was used to handle data from the included studies and to examine heterogeneity. All included studies for diagnostic performance were combined with sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratios (DORs) with 95% confidence intervals (CIs), summary receiver operating characteristic (SROC) curves, and areas under the SROC curves (AUC). Results: A total of 18 studies and 3,865 patients were eligible for the final analysis. The pooled sensitivity estimates for HE4 (74.4%) were significantly higher than those for mesothelin (49.3%). The pooled specificity estimates for mesothelin (94.5%) were higher than those for HE4 (85.8%). The pooled DOR estimates for HE4 (26.22) were higher than those for mesothelin (24.01). The SROC curve for HE4 showed better diagnostic accuracy than that for mesothelin. The PLR and NLR of HE4 were 6.33 (95% CI: 3.58 to 11.18) and 0.27 (95% CI: 0.21 to 0.34), respectively. The PLR and NLR for mesothelin were 11.0 (95% CI: 6.21 to 19.59) and 0.51 (95% CI: 0.42 to 0.62), respectively. The combination of the two tumor markers or their combination with CA-125 increased sensitivity and specificity to different extents. Conclusion: The diagnostic accuracy of HE4 in differentiating ovarian cancer from other benign gynecologic diseases is better than that of soluble mesothelin-related protein. Combinations of two or more tumor markers show more sensitivity and specificity.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.176.2-177
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• 2003

Herbal medicines are increasingly being utilized to treat a wide variety of disease processes. In this study, we assayed the preventive and therapeutic effects of aqueous extract from the roots of Platycodon grandilflorum A. DC, Changil (CK) on experimental metastasis induced by melanoma cell (816F10) in C56BL6 mice. The functional specificity of CK was investigated in tumor cell metastasis. (omitted)

• Korean Journal of Health Education and Promotion
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• v.6 no.1
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• pp.60-65
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• 1989

A statistical analysis was made on 15,971 surgically operated patients at D-Medical Center in the year of 1978 and 1988. 1,416 cancer patients among them were classified by sex, age, and malignant tumor site. The obtained results indicated that trend of male cancer was generally similar to the results of nation wide study. But, specific phenomenon was found in the case of female cancer in Daegu-Kyungbuk area. Among females the frequency rank was uterine cervix (35.77%), breast (17.97%), stomach (11.65%) in 1988. The frequency of uterine cervix was higher than other area. Breast cancer was highly ranked tumor compare with other area, and its age distribution also appeared in much younger decade.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.56-57
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• 2006

The ultra pH-sensitive polymeric mixed micelles based on poly(L-histidine) chemistry and constructed from block copolymers containing polyHis, present four functionalities as decreasing pH: ligand exposure at pH 7.0, micelle destabilization below pH 6.8, enhanced DOX release and endosomal membrane disruption. The first functionality is expected to endow tumor pH specificity to nonspecific ligands and the rest ones may help to treat solid tumors that are hard-to-treat by conventional chemotherapy (resistant tumors). The concept was proven in vitro studies and in vivo model.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3031-3035
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• 2012

Background: Though open surgical biopsy is the procedure of choice for the diagnosis of bone tumors, many disadvantages are associated with this approach. The present study was undertaken to evaluate the role of fine needle aspiration cytology (FNAC) as a diagnostic tool in cases of bony tumors and tumor-like lesions which may be conducted in centers where facilities for surgical biopsies are inadequate. Methods: The study population consisted of 51 cases presenting with a skeletal mass. After clinical evaluation, radiological correlation was done to assess the nature and extent of each lesion. Fine needle aspiration was performed aseptically and smears were prepared. Patients subsequently underwent open surgical biopsy and tissue samples were obtained for histopathological examination. Standard statistical methods were applied for analysis of data. Results: Adequate material was not obtained even after repeated aspiration in seven cases, six of which were benign. Among the remaining 44 cases, diagnosis of malignancy was correctly provided in 28 (93.3%) out of 30 cases and categorical diagnosis in 20 (66.67%). Interpretation of cytology was more difficult in cases of benign and tumor-like lesions, with a categorical opinion only possible in seven (50%) cases. Statistical analysis showed FNAC with malignant tumors to have high sensitivity (93.3%), specificity (92.9%) and positive predictive value of 96.6%, whereas the negative predictive value was 86.7%. Conclusion: FNAC should be included in the diagnostic workup of a skeletal tumor because of its simplicity and reliability. However, a definitive pathologic diagnosis heavily depends on compatible clinical and radiologic features which can only be accomplished by teamwork. The cytological technique applied in this study could detect many bone tumors and tumor-like conditions and appears particularly suitable as a diagnostic technique for rural regions of India as other developing countries.

• The Korean Journal of Cytopathology
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• v.1 no.1
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• pp.18-26
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• 1990

CT guided percutaneous fine-needle aspiration (FNA) of the liver for both cytologic and histologic examination has great value in diagnosing liver malignancy. From March, 1986 to April, 1990, 62 patients with the clinical impression of liver malignancy underwent CT guided percutaneous FNA biopsy. Of these, 43 cases were reviewed for this study, 19 were reported to be liver cell carcinoma, 2 were adenocarcinoma, 11 were reported as anaplastic cell present, and the rest (11 cases) were negative (9) or necrotic (2). Among the 11 cases of the last group, 9 were diagnosed as liver cell carcinoma and 2 were necrotic histologically. Retrospective review, in order to clarify the cause of cytologic diagnostic error, of both cytologic and histologic slides of all cases showed discordance of 23% between these diagnoses and sensitivity is 93.9% and specificity is 90.9%. The reasons were as follows ; 1) the lack of awareness of tumor cells of well differentiated liver cell carcinoma (4 cases), 2) missed tumor cells due to too scanty cellularity (1 case), 3) improper smear (2 cases) and no tumor cell In the cytologic smears (3 cases). In such cases, at the initiation of FNA, a correct diagnosis of liver malignancy could only be made by a combination of cytologic and histologic examinations. However after three years' experience we can conclude that cytomorphologic features of liver cell carcinoma are sufficiently distinctive from other liver malignancies to be diagnostic.

• Biomolecules & Therapeutics
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• v.23 no.6
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• pp.493-509
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• 2015

Antibody-drug conjugates utilize the antibody as a delivery vehicle for highly potent cytotoxic molecules with specificity for tumor-associated antigens for cancer therapy. Critical parameters that govern successful antibody-drug conjugate development for clinical use include the selection of the tumor target antigen, the antibody against the target, the cytotoxic molecule, the linker bridging the cytotoxic molecule and the antibody, and the conjugation chemistry used for the attachment of the cytotoxic molecule to the antibody. Advancements in these core antibody-drug conjugate technology are reflected by recent approval of Adectris$^{(R)}$(anti-CD30-drug conjugate) and Kadcyla$^{(R)}$(anti-HER2 drug conjugate). The potential approval of an anti-CD22 conjugate and promising new clinical data for anti-CD19 and anti-CD33 conjugates are additional advancements. Enrichment of antibody-drug conjugates with newly developed potent cytotoxic molecules and linkers are also in the pipeline for various tumor targets. However, the complexity of antibody-drug conjugate components, conjugation methods, and off-target toxicities still pose challenges for the strategic design of antibody-drug conjugates to achieve their fullest therapeutic potential. This review will discuss the emergence of clinical antibody-drug conjugates, current trends in optimization strategies, and recent study results for antibody-drug conjugates that have incorporated the latest optimization strategies. Future challenges and perspectives toward making antibody-drug conjugates more amendable for broader disease indications are also discussed.