Uncovering the power of neurofeedback: a meta-analysis of its effectiveness in treating major depressive disorders.

Neurofeedback, a non-invasive intervention, has been increasingly used as a potential treatment for major depressive disorders. However, the effectiveness of neurofeedback in alleviating depressive symptoms remains uncertain. To address this gap, we conducted a comprehensive meta-analysis to evaluate the efficacy of neurofeedback as a treatment for major depressive disorders. We conducted a comprehensive meta-analysis of 22 studies investigating the effects of neurofeedback interventions on depression symptoms, neurophysiological outcomes, and neuropsychological function. Our analysis included the calculation of Hedges' g effect sizes and explored various moderators like intervention settings, study designs, and demographics. Our findings revealed that neurofeedback intervention had a significant impact on depression symptoms (Hedges' g = -0.600) and neurophysiological outcomes (Hedges' g = -0.726). We also observed a moderate effect size for neurofeedback intervention on neuropsychological function (Hedges' g = -0.418). As expected, we observed that longer intervention length was associated with better outcomes for depressive symptoms (ß = -4.36, P < 0.001) and neuropsychological function (ß = -2.89, P = 0.003). Surprisingly, we found that shorter neurofeedback sessions were associated with improvements in neurophysiological outcomes (ß = 3.34, P < 0.001). Our meta-analysis provides compelling evidence that neurofeedback holds promising potential as a non-pharmacological intervention option for effectively improving depressive symptoms, neurophysiological outcomes, and neuropsychological function in individuals with major depressive disorders.

Clinical best practices in interdisciplinary management of human epidermal growth factor receptor 2 antibody-drug conjugates-induced interstitial lung disease/pneumonitis: An expert consensus in China.

Antibody-drug conjugates (ADCs) have demonstrated effectiveness in treating various cancers, particularly exhibiting specificity in targeting human epidermal growth factor receptor 2 (HER2)-positive breast cancer. Recent advancements in phase 3 clinical trials have broadened current understanding of ADCs, especially trastuzumab deruxtecan, in treating other HER2-expressing malignancies. This expansion of knowledge has led to the US Food and Drug Administration's approval of trastuzumab deruxtecan for HER2-positive and HER2-low breast cancer, HER2-positive gastric cancer, and HER2-mutant nonsmall cell lung cancer. Concurrent with the increasing use of ADCs in oncology, there is growing concern among health care professionals regarding the rise in the incidence of interstitial lung disease or pneumonitis (ILD/p), which is associated with anti-HER2 ADC therapy. Studies on anti-HER2 ADCs have reported varying ILD/p mortality rates. Consequently, it is crucial to establish guidelines for the diagnosis and management of ILD/p in patients receiving anti-HER2 ADC therapy. To this end, a panel of Chinese experts was convened to formulate a strategic approach for the identification and management of ILD/p in patients treated with anti-HER2 ADC therapy. This report presents the expert panel's opinions and recommendations, which are intended to guide the management of ILD/p induced by anti-HER2 ADC therapy in clinical practice.

Predominance of hyperprogression in mucosal melanoma during anti-PD-1 monotherapy treatment.

BACKGROUND: A minority subset of immunotherapy patients manifests hyperprogressive disease (HPD), with the disparity in melanoma subtypes yet to be reported. This study aimed to delineate the proportion and prognosis of HPD in patients receiving anti-PD-1 monotherapy and to identify patient with HPD clinical characteristics across melanoma subtypes to inform clinical decision making. METHODS: Utilizing 4 established HPD definitions, the incidence of HPD in patients with advanced melanoma on anti-PD-1 monotherapy was determined. The incidence rates and prognostic abilities of various HPD definitions were compared to elect the most effective one. This facilitated a comparative analysis of subtypes and clinical features between patients with HPD and traditional progression. RESULTS: A total of 262 patients with advanced melanoma treated with anti-PD-1 monotherapy from 5 prospectively registered clinical trials were included in the study. The objective response rate (ORR) and disease control rate (DCR) was 21% and 58%, respectively, with 42% showcasing progression disease. The HPD incidences by 4 definitions were 13.2%, 16.8%, 10.8%, and 28.2%. All definitions effectively segregated HPD patients, with significantly poorer outcome than other progressive patients. The Delta TGR > 100 definition was the most indicative of a reduced overall survival, corroborated by the highest hazard ratio and statistical significance. The number of metastatic organs over 2 is a risk factor for HPD (OR = 4.18, P = .0103). Mucosal melanoma was the HPD prevalent subtype (OR = 3.13, P = .0489) in multivariable analysis, which is also indicated by RECIST criteria (P = .005). CONCLUSION: A delta TGR exceeding 100 best identified HPD patients in the advanced melanoma population treated with anti-PD-1 monotherapy. Hyperprogression was notably prevalent in mucosal melanoma patients with multiple metastatic organs. Caution against HPD is warranted when applying anti-PD-1 monotherapy in mucosal subtype.

Experimental study of modified Tavis-Cummings model with directly-coupled superconducting artificial atoms.

The Tavis-Cummings model is intensively investigated in quantum optics and has important applications in generation of multi-atom entanglement. Here, we employ a superconducting circuit quantum electrodynamic system to study a modified Tavis-Cummings model with directly-coupled atoms. In our device, three superconducting artificial atoms are arranged in a chain with direct coupling through fixed capacitors and strongly coupled to a transmission line resonator. By performing transmission spectrum measurements, we observe different anticrossing structures when one or two qubits are resonantly coupled to the resonator. In the case of the two-qubit Tavis-Cummings model without qubit-qubit interaction, we observe two dips at the resonance point of the anticrossing. The splitting of these dips is determined by Δ λ=2g12+g32, where g1 and g3 are the coupling strengths between Qubit 1 and the resonator, and Qubit 3 and the resonator, respectively. The direct coupling J12 between the two qubits results in three dressed states in the two-qubit Tavis-Cummings model at the frequency resonance point, leading to three dips in the transmission spectrum. In this case, the distance between the two farthest and asymmetrical dips, arising from the energy level splitting, is larger than in the previous case. The frequency interval between these two dips is determined by the difference in eigenvalues (Δ λ=ε 1+-ε 1-), obtained through numerical calculations. What we believe as novel and intriguing experimental results may potentially advance quantum optics experiments, providing valuable insights for future research.

Evolving cancer resistance to anti-PD-1/PD-L1 antibodies in melanoma: Comprehensive insights with future prospects.

Immunotherapy has transformed the treatment of advanced melanoma. However, up to two-thirds of patients experience disease progression after initially achieving a response to immunotherapy. Furthermore, most research has focused on cutaneous melanoma rather than acral or mucosal melanoma, although the latter predominates in Asian populations. In this review, we examine and summarize current definitions of resistance to immunotherapy and the epidemiology of resistance to PD-1 inhibition. We also review the available literature on molecular mechanisms of resistance, including how the tumor mutational landscape and tumor microenvironments of immunotherapy-resistant acral and mucosal melanomas may influence resistance. Finally, we review strategies for overcoming resistance to PD-1 inhibition and summarize completed studies and ongoing clinical trials. Our review highlights that improving the understanding of resistance mechanisms, optimizing existing therapies and further studying high-risk populations would maximize the potential of immunotherapy and result in optimized treatment outcomes for patients with melanoma.

SOX10 deficiency-mediated LAMB3 upregulation determines the invasiveness of MAPKi-resistant melanoma.

Melanoma that develops adaptive resistance to MAPK inhibitors (MAPKi) through transcriptional reprograming-mediated phenotype switching is associated with enhanced metastatic potential, yet the underlying mechanism of this improved invasiveness has not been fully elucidated. In this study, we show that MAPKi-resistant melanoma cells are more motile and invasive than the parental cells. We further show that LAMB3, a ß subunit of the extracellular matrix protein laminin-332 is upregulated in MAPKi-resistant melanoma cells and that the LAMB3-Integrin α3/α6 signaling mediates the motile and invasive phenotype of resistant cells. In addition, we demonstrate that SOX10 deficiency in MAPKi-resistant melanoma cells drives LAMB3 upregulation through TGF-ß signaling. Transcriptome profiling and functional studies further reveal a FAK/MMPs axis mediates the pro-invasiveness effect of LAMB3. Using a mouse lung metastasis model, we demonstrate LAMB3 depletion inhibits the metastatic potential of MAPKi-resistant cells in vivo. In summary, this study identifies a SOX10low/TGF-ß/LAMB3/FAK/MMPs signaling pathway that determines the migration and invasion properties of MAPKi-resistant melanoma cells and provide rationales for co-targeting LAMB3 to curb the metastasis of melanoma cells in targeted therapy.

T-2 toxin-induced damage to articular cartilage in rats coincided with impaired autophagy linked to the HIF-1α/AMPK signaling axis.

T-2 toxin is one of the most toxic mycotoxins. People are primarily exposed to T-2 toxin through the consumption of spoiled food, typically over extended periods and at low doses. T-2 toxin can cause damage to articular cartilage. However, the exact mechanism is not fully understood. In this experiment, 36 male rats were divided into a control group, a solvent control group, and a T-2 toxin group. The rats in the T-2 toxin group were orally administered the toxin at a dosage of 100 ng/g BW/Day. The damage to articular cartilage and key proteins associated with the autophagy process and the HIF-1α/AMPK signaling axis was assessed at 4, 8, 12, and 16 weeks. Our findings indicate that T-2 toxin-induced damage to articular cartilage in rats coincided with impaired autophagy linked to the HIF-1α/AMPK signaling pathway. This study offers novel insights into the precise mechanism underlying T-2 toxin-induced damage to articular cartilage.

[Lead Removal from Water by Calcium-containing Biochar with Saturated Phosphate].

Calcium-containing biochar （ES-BC） was prepared by pyrolyzing eggshell and kitchen wastes， and the ES-BC composite was used to remove phosphate （marked as ES-BC/P）. Based on the high affinity of phosphate and carbonate to lead， the ES-BC/P was then used to remove lead from the water. The results showed that， in the appropriate dosage， ES-BC/P could remove lead efficiently at different initial concentrations （1-100 mg·L-1）， and the removal efficiency could reach to 99%. Meanwhile， the release of phosphorus could be ignored after the reaction. As ES-BC/P was alkaline， and the lead-containing solution was weakly acidic， the addition of ES-BC/P could adjust the pH of the system automatically. The reaction kinetics and isotherm experiments showed that the lead removal by ES-BC/P was mainly monolayer chemisorption with a maximum adsorption capacity of 493.12 mg·g-1 （318 K）. The characterization results showed that lead was mainly removed through the ion exchanges of Pb2+ in the solution with Ca2+ in ES-BC/P. Then， the Pb2+ combined with CO32- and PO42- to form many precipitates， including Pb5（PO4）3OH， Pb10（PO4）6（OH）2， PbCO3， and Pb3（CO3）2（OH）2. In summary， the ES-BC/P material could achieve the efficient removal of lead from the water， thereby realizing the resource utilization of the wastes.

Natural history of bone-only metastasis in renal cell carcinoma.

BACKGROUND: Bone metastasis (BM) is considered a poor prognostic factor of renal cell carcinoma (RCC). Confusion exists regarding how to deal with RCC patients with bone-only metastasis. PATIENTS AND METHODS: The clinical data of consecutive RCC patients with bone-only metastasis at Peking University Cancer Hospital between 2006 and 2018 were retrospectively collected and analyzed. RESULTS: Fifty-four eligible patients were screened from an RCC database of 1,878 metastatic patients. After a median follow-up of 43.6 m, 61.1% of the patients were presented with progression of prior BM or new BM. The progression-free survival (PFS) and overall survival (OS) was 16.2 m (95%CI: 11.4-21.0) and 65.2 m, respectively. For the 30 patients with oligo-metastasis (≤3 loci) and 24 ones with multiple-metastasis (>3 loci), the median OS was not reached and 42.0m (95%CI: 12.7-71.2) with statistical difference (P < 0.001). In the oligo-metastasis group, the median PFS of the 15 patients treated with local therapy and of the 13 patients treated with systemic therapy was 14.2 m (95%CI: 5.3-23.3) and 18.0 m (95%CI:15.4-20.6), respectively. In the multiple-metastasis group, the median PFS and OS of the 18 patients treated with systemic therapy was 16.6 m (95%CI: 7.5-25.7) and 63.9 m (95%CI: 21.8-106.0), respectively. Univariate analysis and multivariate analysis showed that the number of metastatic sites (oligo/multiple) and International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) score, RCC pathological subtype were significantly associated with prognosis (P < 0.05). CONCLUSION: RCC patients with bone-only metastases have a favorable prognosis. The number of metastatic sites, IMDC, RCC pathological subtype could serve as survival predictors, which might provide clue of treatment modality.

Comparative Epigenetic Profiling Reveals Distinct Features of Mucosal Melanomas Associated with Immune Cell Infiltration and Their Clinical Implications.

Mucosal melanoma exhibits limited responsiveness to anti-PD-1 therapy. However, a subgroup of mucosal melanomas, particularly those situated at specific anatomic sites like primary malignant melanoma of the esophagus (PMME), display remarkable sensitivity to anti-PD-1 treatment. The underlying mechanisms driving this superior response and the DNA methylation patterns in mucosal melanoma have not been thoroughly investigated. We collected tumor samples from 50 patients with mucosal melanoma, including 31 PMME and 19 non-esophageal mucosal melanoma (NEMM). Targeted bisulfite sequencing was conducted to characterize the DNA methylation landscape of mucosal melanoma and explore the epigenetic profiling differences between PMME and NEMM. Bulk RNA sequencing and multiplex immunofluorescence staining were performed to confirm the impact of methylation on gene expression and immune microenvironment. Our analysis revealed distinct epigenetic signatures that distinguish mucosal melanomas of different origins. Notably, PMME exhibited distinct epigenetic profiling characterized by a global hypermethylation alteration compared with NEMM. The prognostic model based on the methylation scores of a 7-DMR panel could effectively predict the overall survival of patients with PMME and potentially serve as a prognostic factor. PMME displayed a substantial enrichment of immune-activating cells in contrast to NEMM. Furthermore, we observed hypermethylation of the TERT promoter in PMME, which correlated with heightened CD8+ T-cell infiltration, and patients with hypermethylated TERT were likely to have improved responses to immunotherapy. Our results indicated that PMME shows a distinct methylation landscape compared with NEMM, and the epigenetic status of TERT might be used to estimate prognosis and direct anti-PD-1 treatment for mucosal melanoma. SIGNIFICANCE: This study investigated the intricate epigenetic factor of mucosal melanomas contributed to the differential immune checkpoint inhibitor response, and found that PMME exhibited a global hypermethylation pattern and lower gene expression in comparison to NEMM. TERT hypermethylation may contribute to the favorable responses observed in patients with mucosal melanoma undergoing immunotherapy.

IBI310 (anti-CTLA-4 antibody) monotherapy or in combination with sintilimab in advanced melanoma or urothelial carcinoma.

IBI310 is a recombinant fully human IgG1 antibody against cytotoxic T lymphocyte antigen 4. This study was conducted to evaluate IBI310 monotherapy or combination therapy with sintilimab in the patients with advanced melanoma or urothelial carcinoma (UC). Patients in phase 1a received IBI310 at 0.3/1/2/3 mg/kg intravenously (IV) every 3 weeks (Q3W) following the accelerated titration and 3 + 3 escalation design. Patients in phase 1b received IBI310 (1/2/3 mg/kg IV, Q3W) plus sintilimab (200 mg IV, Q3W) for four cycles, followed by sintilimab maintenance therapy. The phase 1b expansion of IBI310 plus sintilimab was performed in patients with advanced melanoma or UC. Overall, 53 patients were enrolled, including 10 patients with melanoma in phase 1a, 34 with melanoma, and 9 with UC in phase 1b. Overall, 94.3% of patients (50/53) experienced at least one treatment-related adverse event (TRAE) with most being grade 1-2; 26.4% of patients (14/53) experienced grade 3 or higher TRAEs. In phase 1a, the disease control rate (DCR) was 50.0% (95% confidence interval [CI], 18.7%-81.3%). In phase 1b, the objective response rate (ORR) and DCR were 17.6% (95% CI, 6.8%-34.5%) and 44.1% (95% CI, 27.2%-62.1%), respectively, for melanoma, and were 22.2% (95% CI, 2.8%-60.0%) and 66.7% (95% CI, 29.9%-92.5%), respectively, for UC. IBI310 monotherapy or combination therapy with sintilimab was well tolerated with favorable antitumor activity across patients with advanced melanoma and UC.

Efficacy and Safety of Postoperative Adjuvant Radiation Therapy in Resected Nasal Cavity and Paranasal Sinus Mucosal Melanoma: A Combined Analysis.

PURPOSE: Mucosal melanoma of the nasal cavity and paranasal sinuses (NPMM) is a highly aggressive disease. The role of postoperative adjuvant radiation therapy is controversial. METHODS AND MATERIALS: A total of 300 patients with NPMM treated between March 2009 and January 2020 were divided into surgery alone (SA; 158 patients) and surgery plus radiation therapy (SR; 142 patients) groups. Postoperative radiation therapy was recommended, with a total dose of 65 to 70 Gy/30 to 35 fractions to the gross tumor volume and 60 Gy/30 fractions to the clinical target volume. The primary endpoint was relapse-free survival. Secondary endpoints included local recurrence-free survival, distant metastasis-free survival, and overall survival. RESULTS: At a median follow-up of 50.0 months, relapse-free survival in the SA and SR groups was 9.8 and 15.2 months (hazard ratio [HR], 0.714; 95% CI, 0.546-0.933; P = .014). Distant metastasis-free survival in the SA and SR groups was 23.8 and 21.3 months (HR, 0.896; 95% CI, 15.7-31.9 vs 13.3-29.3; P = .457). Overall survival in the SA and SR groups was 31.0 and 35.1 months (HR, 0.816; 95% CI, 25.7-36.3 vs 27.1-43.2; P = .178). For patients with stage IVA NPMM, radiation therapy reduced the incidence of relapse by 0.43-fold. CONCLUSIONS: Postoperative radiation therapy played a crucial role in the local control of resected NPMM, especially in patients with stage T4a or IVA disease.

Pembrolizumab Versus High-Dose Interferon-α2b as Adjuvant Therapy for Pediatric Melanoma: A Retrospective Study.

INTRODUCTION: Pembrolizumab is well-tolerated in pediatric patients with advanced tumors, consistent with results in adults. However, information on the safety and efficacy of adjuvant pembrolizumab in children and adolescents with melanoma is lacking. OBJECTIVES: To compare pembrolizumab versus high-dose interferon-α2b (HDI) as adjuvant therapy in pediatric patients with melanoma. METHODS: We performed a retrospective study of pediatric patients diagnosed with melanoma between January 2008 and April 2022. Relapse-free survival (RFS) and the 1-year RFS rate were compared between patients receiving adjuvant pembrolizumab or HDI. RESULTS: Seventy-five pediatric patients with melanoma were screened from a database of 6,013 patients. Twenty-four patients were finally enrolled, of whom 9 received pembrolizumab and 15 received HDI as adjuvant therapy. By August 31, 2022, the median follow-up times were 23.6 months and 98.7 months in the pembrolizumab and HDI groups, respectively. There was no significant difference in median RFS between two groups (not reached versus 38.7 months, P = 0.11). The median overall survival was not reached in either group. The 1-year RFS rates were 88.9% and 66.7% in the pembrolizumab and HDI groups, respectively. All adverse events in the pembrolizumab group were grade 1 or 2, but grade 3-5 adverse events occurred in two (13%) patients receiving HDI. CONCLUSIONS: RFS was similar in pediatric patients with melanoma receiving adjuvant pembrolizumab or HDI, but pembrolizumab was associated with a reduced risk of recurrence and a more favorable safety profile. However, due to the small sample size and differences in follow-up time, larger and prospective studies are still warranted to explore better adjuvant therapies for pediatric melanoma.

A phase II study of efficacy and safety of the MEK inhibitor tunlametinib in patients with advanced NRAS-mutant melanoma.

BACKGROUND: NRAS-mutant melanoma is an aggressive subtype with poor prognosis; however, there is no approved targeted therapy to date worldwide. METHODS: We conducted a multicenter, single-arm, phase II, pivotal registrational study that evaluated the efficacy and safety of the MEK inhibitor tunlametinib in patients with unresectable, stage III/IV, NRAS-mutant melanoma (NCT05217303). The primary endpoint was objective response rate (ORR) assessed by independent radiological review committee (IRRC) per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. The secondary endpoints included progression-free survival (PFS), disease control rate (DCR), duration of response(DOR), overall survival (OS) and safety. FINDINGS: Between November 2, 2020 and February 11, 2022, a total of 100 patients were enrolled. All (n = 100) patients received at least one dose of tunlametinib (safety analysis set [SAS]) and 95 had central laboratory-confirmed NRAS mutations (full analysis set [FAS]). In the FAS, NRAS mutations were observed at Q61 (78.9%), G12 (15.8%) and G13 (5.3%). The IRRC-assessed ORR was 35.8%, with a median DOR of 6.1 months. The median PFS was 4.2 months, DCR was 72.6% and median OS was 13.7 months. Subgroup analysis showed that in patients who had previously received immunotherapy, the ORR was 40.6%. No treatment-related deaths occurred. INTERPRETATION: Tunlametinib showed promising antitumor activity with a manageable safety profile in patients with advanced NRAS-mutant melanoma, including those who had prior exposure to immunotherapy. The findings warrant further validation in a randomized clinical trial.

Benefit, recurrence pattern, and toxicity to adjuvant anti-PD-1 monotherapy varies by ethnicity and melanoma subtype: An international multicenter cohort study.

Background: Anti-Program-Death-1 (PD-1) is a standard adjuvant therapy for patients with resected melanoma. We hypothesized that there are discrepancies in survival, recurrence pattern and toxicity to adjuvant PD-1 between different ethnicities and melanoma subtypes. Objective: We performed a multicenter cohort study incorporating 6 independent institutions in Australia, China, Japan, and the United States. The primary outcomes were recurrence free survival (RFS) and overall survival (OS). Secondary outcomes were disease recurrence patterns and toxicities. Results: In total 534 patients were included. East-Asian/Hispanic/African reported significantly poorer RFS/OS. Nonacral cutaneous or melanoma of unknown primary reported the best RFS/OS, followed by acral, and mucosal was the poorest. Within the nonacral cutaneous or melanoma of unknown primary subtypes, East-Asian/Hispanic/African reported significantly poorer RFS/OS than Caucasian. In the multivariate analysis incorporating ethnicity/melanoma-subtype/age/sex/stage/lactate dehydrogenase/BRAF (v-Raf murine sarcoma viral oncogene homolog B)-mutation/adjuvant radiotherapy, East-Asian/Hispanic/African had independently significantly poorer outcomes (RFS: HR, 1.71; 95% CI, 1.19-2.44 and OS: HR, 2.34; 95% CI, 1.39-3.95), as was mucosal subtype (RFS: HR, 3.25; 95% CI, 2.04-5.17 and OS: HR, 3.20; 95% CI, 1.68-6.08). Mucosal melanoma was an independent risk factor for distant metastasis, especially liver metastasis. East-Asian/Hispanic/African had significantly lower incidence of gastrointestinal/musculoskeletal/respiratory/other-rare-type-toxicities; but higher incidences of liver toxicities. Limitations: A retrospective study. Conclusions: Ethnicity and melanoma subtype are associated with survival and recurrence pattern in melanoma patients treated with adjuvant anti-PD-1. Toxicity profile differs by ethnicity and may require a precision toxicity surveillance strategy.

Assessment of the expression pattern of HER2 and its correlation with HER2-targeting antibody-drug conjugate therapy in urothelial cancer.

Background: Human epidermal growth factor receptor 2 (HER2) overexpression is related to anti-HER2 therapy in many tumors. RC48- antibody-drug conjugate (ADC) has shown promising efficacy in patients with HER2-positive locally advanced or metastatic urothelial carcinoma (UC). The characteristic expression and scoring systems of HER2 are nonexistent in UC. We aimed to explore HER2 status and its correlation with the efficacy of HER2-targeting ADC therapy in UC. Methods: A total of 137 and 43 patients were enrolled in cohort 1 and cohort 2, respectively, from March 2009 to December 2018. The patients in cohort 2 were enrolled in a phase II study of RC48-ADC. UC samples were tested for HER2 status using immunohistochemistry (IHC) and/or fluorescence in situ hybridization (FISH). The 2018 ASCO/CAP HER2 scoring system was adopted and modified to score HER2 expression in UC. Results: The HER2-positive (IHC 2+ or 3+) rate was 24.1% (33/137). In HER2 IHC 2+ or 3+ patients, the HER2 gene amplification rate was 31% (13/42). The objective response rates (ORRs) in RC48-ADC-treated patients with IHC 3+, IHC 2+ and FISH+, IHC 2+ and FISH- were 58.8%, 66.7% and 40%, respectively. The ORR showed a trend toward a better benefit for RC48-ADC therapy in patients with HER2 amplification than in those without amplification (61.5% vs. 44.8%, P = 0.059). The heterogeneity of HER2 expression in the primary tumor was 55.5% (15/27), and the ORR was not significantly different between patients with tumor heterogeneity and homogeneity. Conclusions: IHC testing should be performed to assess the HER2 status before the initiation of HER2-ADC therapy. There was a trend toward a better benefit for patients with HER2 amplification, and tumor heterogeneity did not influence the drug efficacy.