Min Chong Kim, Eun Yoon Cho, So Yeon Park, Hee Jin Lee, Ji Shin Lee, Jee Yeon Kim, Ho-chang Lee, Jin Ye Yoo, Hee Sung Kim, Bomi Kim, Wan Seop Kim, Nari Shin, Young Hee Maeng, Hun Soo Kim, Sun Young Kwon, Chungyeul Kim, Sun-Young Jun, Gui Young Kwon, Hye Jeong Choi, So Mang Lee, Ji Eun Choi, Ae Ri An, Hyun Joo Choi, EunKyung Kim, Ahrong Kim, Ji-Young Kim, Jeong Yun Shim, Gyungyub Gong, Young Kyung Bae
Cancer Res Treat. 2024;56(4):1096-1104. Published online March 6, 2024
Purpose Notable effectiveness of trastuzumab deruxtecan in patients with human epidermal growth factor receptor 2 (HER2)–low advanced breast cancer (BC) has focused pathologists’ attention. We studied the incidence and clinicopathologic characteristics of HER2-low BC, and the effects of immunohistochemistry (IHC) associated factors on HER2 IHC results.
Materials and Methods The Breast Pathology Study Group of the Korean Society of Pathologists conducted a nationwide study using real-world data on HER2 status generated between January 2022 and December 2022. Information on HER2 IHC protocols at each participating institution was also collected.
Results Total 11,416 patients from 25 institutions included in this study. Of these patients, 40.7% (range, 6.0% to 76.3%) were classified as HER2-zero, 41.7% (range, 10.5% to 69.1%) as HER2-low, and 17.5% (range, 6.7% to 34.0%) as HER2-positive. HER2-low tumors were associated with positive estrogen receptor and progesterone receptor statuses (p < 0.001 and p < 0.001, respectively). Antigen retrieval times (≥ 36 minutes vs. < 36 minutes) and antibody incubation times (≥ 12 minutes vs. < 12 minutes) affected on the frequency of HER2 IHC 1+ BC at institutions using the PATHWAY HER2 (4B5) IHC assay and BenchMark XT or Ultra staining instruments. Furthermore, discordant results between core needle biopsy and subsequent resection specimen HER2 statuses were observed in 24.1% (787/3,259) of the patients.
Conclusion The overall incidence of HER2-low BC in South Korea concurs with those reported in previously published studies. Significant inter-institutional differences in HER2 IHC protocols were observed, and it may have impact on HER2-low status. Thus, we recommend standardizing HER2 IHC conditions to ensure precise patient selection for targeted therapy.
Citations
Citations to this article as recorded by
Impact of immunohistochemistry staining conditions on the incidence of human epidermal growth factor receptor 2 (HER2)-low breast cancer Min Chong Kim, Sun Young Kwon, Hye Ra Jung, Young Kyung Bae Virchows Archiv.2024; 485(6): 1117. CrossRef
Breast Cancer: Extracellular Matrix and Microbiome Interactions Lourdes Herrera-Quintana, Héctor Vázquez-Lorente, Julio Plaza-Diaz International Journal of Molecular Sciences.2024; 25(13): 7226. CrossRef
We report on a case of malignant pleural effusion as initial metastatic presentation of occult gastric cardia cancer in a young woman. To the best of our knowledge, this is the first report of gastric adenocarcinoma metastasized to pleura as an initial presentation. Location of cardia and signet ring cell histology may contribute to the manifestation. Utilization of PET/CT was helpful for proper diagnosis. For patients with such distinct clinical presentations, it would be appropriate to consider gastric cancer as one of the possible primary sites.
PURPOSE Apoptosis is a physiological mechanism for deleting cells from the body for development and homeostasis.
Exogenous cytokines such as tumor necrosis factor alpha (TNFalpha) and transforming growth factor beta (TGF beta) are known to modulate apoptosis, thus can provide a new therapeutic modality for various malignancies. We studied whether TNFalpha or TGFbeta can induce apoptosis or exert antiproliferative effect on human gastric cancer cell line (AGS) and which genes are involved in the cytokine-induced apoptotic pathway. MATERIALS AND METHODS To examine the effect of TNFalpha or TGF beta on AGS cell line (human gastric adenocarcimoma), we performed following tests; MTT test, trypan blue dye exclusion assay and colony forming efficiency. Total DNA was extracted from the TNFalpha-treated AGS cells and DNA ladder was detected as the hallmark of apoptosis, and flow cytometry analysis was performed for another apoptotic index. The effects of TNFalpha on c-myc expression was observed using RT-PCR. RESULTS TNFalpha suppressed AGS cell growth, in a time- and dose-dependent manner, but TGFbeta had no effect on AGS cell growth. Electrophoretic analysis of total cellular DNA revealed the pattern of internucleosomal DNA cleavage, which is specific for apoptosis and the effect was observed from 24 to 72 hrs after 50 ng/ml TNFalpha treatment.
Time-dependent increse of apoptotic cells by TNFalpha was detected by flow cytometry analysis. Morphological changes such as cell to cell contacts and extension of cell processes were observed in TNFalpha-treated AGS cells.
RT-PCR using c-myc primers showed thatthe mRNA levels were increased 6 hrs after TNFalpha treatment and persisted for 72 hrs. CONCLUSION It is suggested that TNFalpha, but not TGF beta, functions as an important inducer of apoptosis in AGS cell line, and c-myc may function as a critical endogenous activator of the pathway leading to cell death of AGS cells.