Neoadjuvant Combination Therapy Research Articles

Immune checkpoint inhibitor therapy as a neoadjuvant treatment for muscle-invasive bladder carcinoma

Abstract Background and objectives Immunotherapy has become a standard treatment for patients with advanced urothelial carcinoma, and neoadjuvant immunotherapy is being extensively explored. This review highlights the initial findings and key clinical therapeutic insights on immune checkpoint inhibitors in the early treatment of muscle-invasive bladder cancer across diverse patient populations. Materials and methods Relevant trials were retrieved from PubMed/MEDLINE and clinical trials databases. In addition, abstracts of major international oncology meetings (American Society of Clinical Oncology, American Association for Cancer Research, European Society of Medical Oncology, and European Council of Clinical Oncology) were reviewed until the European Society of Medical Oncology 2023 congress. The review also incorporated results from several exploratory investigations disclosed in recent years. Results This review focused on neoadjuvant immune checkpoint inhibitor monotherapy, combination therapy, and clinical biomarkers in relation to cisplatin-based chemotherapy tolerance. Most available literature consists of clinical investigations involving small sample, single-arm Phase II trials, with the primary endpoint being the pathologic complete response rate. The preliminary results from these studies are promising, demonstrating stage reduction rates comparable to or even exceeding those of standard chemotherapy, without compromising subsequent radical cystectomy. Conclusions Early results of immune checkpoint inhibitors in the neoadjuvant treatment of bladder cancer have demonstrated promising efficacy. However, these findings require confirmation in large Phase III clinical trials, with particular emphasis on long-term survival benefits and identifying patients who respond to treatment.

Functional heterogeneity of cancer-associated fibroblasts with distinct neoadjuvant immunotherapy plus chemotherapy response in esophageal squamous cell carcinoma

Novel neoadjuvant immunotherapy combined with chemotherapy (neoICT) has improved outcomes for patients with esophageal squamous-cell carcinoma (ESCC), but challenges persist in low response rates and therapy resistance. Little is known about the intra-tumoral heterogeneity in the ESCC tumor microenvironment (TME) that underlies differential responses to neoadjuvant therapy. We applied single-cell RNA sequencing (scRNA-seq) profiling and multiplexed immunofluorescence staining to thoroughly decipher the TME in ESCC specimens from a neoadjuvant anti-PD1 combination therapy clinical trial. The cancer-associated fibroblasts (CAFs) population showed the significant alteration in abundance following neoadjuvant therapy. Specifically, IL6 + CCL2 + immunomodulatory CAFs and a novel CD248 + mechanoresponsive CAFs subset exhibited increasing infiltration. Mechanistically, CD248 + mechanoresponsive CAFs approached and lined the tumor nest to physically block the infiltration of CD8 + T cells and drug delivery, while IL6 + CCL2 + immunomodulatory CAFs induced therapeutic resistance with distinct IL-6 expression. Among patients treated with neoICT, we observed prominent CAF-T cell interactions. In particular, the NECTIN2-TIGIT ligand-receptor pair was enriched in treated samples, and TIGIT was identified as the major inhibitory checkpoint of T cells. Our findings demonstrate distinct alterations in TME constituent responses to neoadjuvant immunotherapy and identify functional phenotypes of CAFs associated with unfavorable therapeutic responses in patients. This provides potential targets to enhance responses to neoadjuvant therapy in ESCC.

Dissecting transcriptome signals of anti-PD-1 response in lung adenocarcinoma

Immune checkpoint blockades are actively adopted in diverse cancer types including metastatic melanoma and lung cancer. Despite of durable response in 20–30% of patients, we still lack molecular markers that could predict the patient responses reliably before treatment. Here we present a composite model for predicting anti-PD-1 response based on tumor mutation burden (TMB) and transcriptome sequencing data of 85 lung adenocarcinoma (LUAD) patients who received anti-PD-(L)1 treatment. We found that TMB was a good predictor (AUC = 0.81) for PD-L1 negative patients (n = 20). For PD-L1 positive patients (n = 65), we built an ensemble model of 100 XGBoost learning machines where gene expression, gene set activities and cell type composition were used as input features. The transcriptome-based models showed excellent accuracy (AUC > 0.9) and highlighted the contribution of T cell activities. Importantly, nonresponder patients with high prediction score turned out to have high CTLA4 expression, which suggested that neoadjuvant CTLA4 combination therapy might be effective for these patients. Our data and analysis results provide valuable insights into developing biomarkers and strategies for treating LUAD patients using immune checkpoint inhibitors.

AB048. Evidence of effectiveness of neoadjuvant camrelizumab and apatinib in patients with recurrent high-grade gliomas.

Recurrent high-grade glioma (HGG) is a challenge with limited treatment options and a poor prognosis. We conducted an open-label phase II study: neoadjuvant camrelizumab and apatinib in patients with recurrent high-grade gliomas (NCT04588987), and interim analysis showed very promising results. We are further searching for evidence of the effectiveness of this strategy. Patients with recurrent HGG received neoadjuvant treatment with camrelizumab (intravenous injection 200 mg on day 1) and apatinib (oral 250 mg per day on days 1-7), and 14 days later received surgery for recurrent tumor resection. Sequential therapy began 2 weeks after surgery with the biweekly camrelizumab (200 mg) and 4 weeks after surgery with the daily apatinib (250 mg) until investigator assessed progressive disease or unable to tolerate toxicity. The primary endpoint was overall survival (OS). When patients suspected progress during per-protocol treatment, re-surgery for resection of lesion was done, and the tissue was further examined. Between October 9, 2020, and March 30, 2024, 24 patients were enrolled [19 glioblastomas, one World Health Organization (WHO) grade 4 diffuse astrocytoma, three anaplastic astrocytoma, and one anaplastic oligodendroglioma]. Nineteen patients with interim analysis data, and showed the median progression-free survival (PFS) was 4.8 months [95% confidence interval (CI): 4.4-5.2], the median OS was 12.9 months (95% CI: 9.3-16.4) respectively, with a median follow-up time of 17.5 months (95% CI: 9.0-26.1). There were two patients who suspected progress and received second surgery. One patient showed real tumor progression with active tumor cells. While another patient the histology revealed mainly necrosis with inflammatory cells. Five patients initially showed increased enhancement on magnetic resonance imaging (MRI) but without increased symptoms, and showed continuous improvement when receiving further treatment. This immuno-target combination neoadjuvant therapy in recurrent HGG demonstrated encouraging efficacy and revealed some evidence of efficacy, and worth to further investigate.

Neoadjuvant SHR-1701 with or without chemotherapy in unresectable stage III non-small-cell lung cancer: A proof-of-concept, phase 2 trial

We conducted a proof-of-concept, phase 2 trial to assess neoadjuvant SHR-1701 with or without chemotherapy, followed by surgery or radiotherapy, and then consolidation SHR-1701 in unresectable stage III non-small-cell lung cancer (NSCLC). In the primary cohort of patients receiving neoadjuvant combination therapy (n= 97), both primary endpoints were met, with a post-induction objective response rate of 58% (95% confidence interval [CI] 47-68) and an 18-month event-free survival (EFS) rate of 56.6% (95% CI 45.2-66.5). Overall, 27 (25%) patients underwent surgery; all achieved R0 resection. Among them, 12 (44%) major pathological responses and seven (26%) pathological complete responses were recorded. The 18-month EFS rate was 74.1% (95% CI 53.2-86.7) in surgical patients and 57.3% (43.0-69.3) in radiotherapy-treated patients. Neoadjuvant SHR-1701 with chemotherapy, followed by surgery or radiotherapy, showed promising efficacy with a tolerable safety profile in unresectable stage III NSCLC. Surgical conversion was feasible in a notable proportion of patients and associated with better survival outcomes.

The rationale of reprogramming TREM2+ macrophages for overcoming the resistance to immune checkpoint inhibitors in pancreatic adenocarcinoma.

e14649 Background: Pancreatic ductal adenocarcinoma (PDAC) resists to immune checkpoint inhibitors as single agents. TAMs expressing the triggering receptor expressed on myeloid cells (TREM2) protein were found to be a dominant macrophage population in PDAC; targeting TREM2 has been found to enhance the efficacy of immune checkpoint inhibitor-based therapies in preclinical studies of other malignancies. Here, we studied the role of targeting TREM2 in PDAC by testing the combination of non-depleting anti-TREM2 antibody and anti-PD-1 antibody in a mouse model of PDAC. We also examined the relationship between TREM2 expression and effector T cells in surgically resected human PDAC collected from a previous clinical trial treated with the neoadjuvant combination therapy of nivolumab (anti-PD-1 antibody), urelumab (anti-CD137 agonist antibody), and the pancreatic cancer GVAX vaccine. Methods: C57BL/6 mice were orthotopically implanted with KPC tumors. Anti-TREM2 was injected intraperitoneally (i.p.) once a week and anti-PD-1 was injected i.p. twice a week. Tumor volume was measured by ultrasound. TREM2 was stained on slides which were previously obtained from surgically resected PDACs following the neoadjuvant combination treatment of nivolumab, urelumab, and GVAX and stained for multiple immune cell markers with a multiplex staining-striping immunohistochemistry (IHC) technique. Results: Tumor growth post-tumor implantation was found to be significantly decreased by the anti-PD-1 and anti-TREM2 combination compared with anti-PD-1 alone, anti-TREM2 alone, or control treatment (p < 0.0001). Survival of tumor-bearing mice was significantly prolonged by the anti-PD-1 and anti-TREM2 combination when compared to anti-PD-1(p < 0.05), anti-TREM2(p < 0.05), and control (p < 0.01). Multiplex IHC analysis of human PDACs following neoadjuvant immunotherapy showed a higher density of granzyme B+CD8+ effector T cells correlated with higher density of TREM2+ cells (p = 0.0357). Conclusions: Our study demonstrates the anti-tumor efficacy of anti-TREM2 antibody in combination with an immune checkpoint inhibitor in mouse PDAC. However, the analysis of human PDAC following neoadjuvant immunotherapy suggests that TREM2 on TAMs may be activated following the activation of effector T cells. Taken together, our results suggest that TREM2+ TAMs should be reprogrammed instead of being depleted in the design of anti-TREM2-based therapy for PDAC.

Association of human interpretable features derived from pancreatic ductal adenocarcinoma pathology slides with disease-free survival.

e16368 Background: Pancreatic ductal adenocarcinoma (PDAC) is predicted to be the second cause of cancer death in the US by 2040. For the minority of patients who are candidates for curative-intent surgical resection, a neoadjuvant approach with chemotherapy or chemotherapy followed by chemoradiotherapy (chemoRT) has become the standard of care. The tumor microenvironment (TME) has been recognized as a key factor in therapeutic resistance and disease progression. This study aims to explore the prognostic value of human-interpretable machine learning image features (HIFs) derived from whole-slide H&E images. Methods: Consecutive PDAC patients who underwent neoadjuvant therapy followed by surgical resection were studied in this single-institution retrospective study. Clinical variables collected include tumor site (head/body/tail), surgery extent, histology, sex, age at diagnosis, grade, treatment response (4-point scale), LVI, PNI, resection margin status, pathological TNM staging, number of lymph nodes removed/positive, neoadjuvant strategy (chemotherapy vs chemoRT), and number of neoadjuvant chemo cycles. These factors were analyzed with a multivariable Cox proportional hazards model for disease-free survival (DFS) after surgery. Additionally, 420 human-interpretable image features (HIFs) derived from a commercial machine learning software were analyzed with a univariable Cox model on a binary outcome of 1-yr DFS, applying a Bonferroni correction for multiple comparisons to identify significant predictors. Results: Increased neoadjuvant chemotherapy cycles (HR = 0.62, p = 0.001, [median: 8, IQR: 6-12]) and receipt of combination neoadjuvant therapy (HR = 0.15, p = 0.020, [29% chemo, 71% +chemoRT]) exhibited a protective effect in the multivariable DFS model. 3 HIFs quantifying immune cells and macrophages within the cancerous tissue and its stroma were associated with an improved probability of 1-year DFS. Conclusions: In addition to clinical factors, HIFs may offer valuable insights into the tumor microenvironment's influence on PDAC progression, paving the way for improved prognostic models and therapeutic strategies. Future work will integrate clinical predictors with HIFs in a combined model.

Abstract PS05-09: A single-arm Phase II clinical study of fulvestrant combined with chemotherapy in the neoadjuvant treatment of HR+/HER2- locally advanced breast cancer

Abstract Background: HR+/HER2- breast cancer has been found to be less sensitive to neoadjuvant chemotherapy (NCT), leading to an objective response rate (ORR) of approximately 65%. Endocrine therapy combined with chemotherapy may help improve the ORR in these patients. The objective of this Phase II study was to evaluate the efficacy and safety of adding fulvestrant to NCT in patients with HR+/HER2- locally advanced breast cancer(LABC). Additionally, the study aimed to investigate the association of 18F-FES PET/CT and metabolites with efficacy. Methods: In this single-arm Phase II study, eligible patients were females with histologically confirmed HR+/HER2- LABC (Stage IIB-IIIC). Patients received fulvestrant (500 mg, on days 0, 14, 28, then every 28 days thereafter, every 4 weeks for six cycles) plus AC-T regimen, followed by surgery. Premenopausal women were administered a concomitant GnRH analogue. Patients underwent 18F-FES PET/CT before the initiation of fulvestrant, and plasma samples were collected for LC-MS analysis at baseline. The primary endpoint was ORR. Secondary endpoints included pathological complete response (tpCR) and safety. Results: From December 2020 to September 2022, 36 patients were enrolled. The median age was 53 years (range35-67). 78% were ECOG PS of 1, 69% were postmenopausal, 92% were nodal involved, and 83% were in stage III. After neoadjuvant therapy, the ORR was 86.1%. All patients completed the surgery, with a tpCR rate of 8.3% (3/36). 80.6% (29/36) patients were classified as Miller-Payne (MP) grade ≥3. Grade ≥3 treatment-emergent adverse events (TEAEs) occurred in 22% (8/36) of the participants. The most common TEAEs were neutropenia (13.9%) and leukopenia (8.3%). The expression of ER, PR, and Ki-67 in postoperative pathology significantly decreased compared to baseline (p < 0.05). Additionally, the change in ER expression was significantly correlated with the regression volume of primary breast tumors (R = 0.56, p = 0.0044). The decrease in ER value in patients with MP ≥ 4 was significantly larger than in patients with MP ≤ 3 (p = 0.0054). Among the 36 patients, 24 completed the 18F-FES PET/CT scan before initiating fulvestrant.The average SUVmax in primary breast lesions was 4.17 (range 1.00-12.80). The SUVmax of breast lesions was significantly correlated with clinical efficacy (p = 0.0018) and with changes in ER expression before and after treatment (R = 0.68, p = 0.00023). Meanwhile, the SUVmax of patients with MP ≥ 4 grade was significantly higher than that of patients with MP ≤ 3 grade (p=0.018). A total of 25 plasma samples were available for metabolic analysis. Among these samples, 13 differential metabolites were identified between patients with MP ≥ 4 grade and MP ≤ 3 grade, which were markedly enriched in 19 metabolic pathways. Conclusions: The addition of fulvestrant to NCT showed manageable toxicity and promising antitumor activity for patients with HR+/HER2- LABC. 18F-FES PET/CT might serve as a tool to predict the effectiveness of neoadjuvant combination therapy. Altered metabolites or metabolic pathways might be associated with the response to this combined treatment approach. Keywords: breast cancer, HR+/HER2-, fulvestrant, neoadjuvant treatment, 18F-FES PET/CT Citation Format: Qing Shao, Jing Wu, Ningning Zhang, Xiaohua Zeng. A single-arm Phase II clinical study of fulvestrant combined with chemotherapy in the neoadjuvant treatment of HR+/HER2- locally advanced breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS05-09.

Efficacy and safety of combination neoadjuvant chemo-hormonal therapy and robot-assisted radical prostatectomy for oligometastatic prostate cancer.

Efficacy and safety of combination neoadjuvant chemo-hormonal therapy and robot-assisted radical prostatectomy for oligometastatic prostate cancer.

Neoadjuvant nivolumab plus bevacizumab therapy improves the prognosis of triple-negative breast cancer in humanized mouse models.

The combination of immune checkpoint inhibitors and anti-angiogenic agents has been proposed as a promising strategy to improve the outcome of advanced triple-negative breast cancer (TNBC). However, further investigation is warranted to elucidate the specific mechanisms underlying the effects of combination therapy and its potential as neoadjuvant therapy for early-stage TNBC. In this study, we constructed humanized mouse models by engrafting the human immune system into severely immunodeficient mice and subsequently implanting TNBC cells into the model. The mice were treated with neoadjuvant combination therapy (bevacizumab combined with nivolumab), followed by in vivo imaging system to assess tumor recurrence and metastasis after surgery. The immune microenvironment of tumors was analyzed to investigate the potential mechanisms. Furthermore, we verified the impact of extending the interval before surgery or administering adjuvant therapy after neoadjuvant therapy on the prognosis of mice. Neoadjuvant combination therapy significantly inhibited tumor growth, prevented recurrence and metastasis by normalizing tumor vessels and inducing robust CD8+ T cell infiltration and activation in primary tumors (p < 0.001). In vivo experiments demonstrated that prolonging the interval before surgery or administering adjuvant therapy after neoadjuvant therapy did not enhance its efficacy. The preclinical study has demonstrated the therapeutic efficacy and mechanism of neoadjuvant combination therapy (nivolumab plus bevacizumab) in treating early TNBC.

Liver transplantation for unresectable Klatskin tumor: first long-term outcomes – a single center experience

Objective: to demonstrate the first long-term outcomes of treatment of unresectable hilar cholangiocarcinoma (HCCA) after combined neoadjuvant therapy followed by liver transplantation (LT). Materials and methods. From 2017 to 2023, at the Russian Research Center of Radiology and Surgical Technologies, 10 patients were included in the treatment protocol for unresectable HCCA. Combined neoadjuvant therapy included endobiliary photodynamic therapy (EPDT), regional chemotherapy (RCT) and systemic polychemotherapy (SPCT). Each modality was applied at least three times over a period of four to six months. Patients were placed on the LT waitlist when tumor marker CA19-9 reduced, there was no radiological evidence of disease progression, and there was no evidence of acute cholangitis. Before LT, the recipients underwent diagnostic laparoscopy to exclude carcinomatosis and also evaluation of regional lymph nodes with urgent morphologic examination. In the absence of extrahepatic tumor spread, LT from a deceased donor was performed according to the classical technique with paracaval and hepatoduodenal lymph node dissection, biliodigestive anastomosis using the Roux-en-Y procedure. The operation was performed in six patients. Patient age ranged from 40 to 55 years (mean, 46.3). The mean time from start of treatment to LT was 9.1 months (range 6 to 14). The mean CA19-9 level at the time of LT was 66.5 IU/mL (8 to 212). Results. After combined neoadjuvant treatment, the CA19-9 marker normalized in four patients and there was a 3–4-fold decrease in two patients. Radiological evaluation indicated stable disease in five patients, and a partial response in one. Disease progression was noted in four out of 10 patients. Currently, one of the 6 patients is alive with a follow-up of 34 months. Median (Me) overall survival is 28 months; Me overall survival after LT is 22.2 months; Me survival before progression is 27 months. During long-term follow-up of patients after LT, three patients out of six had disease progression: implantation metastasis (n = 2) at 25 and 27 months follow-up (metastasectomy was performed), carcinomatosis (n = 1) at 20 months follow-up. Conclusion. LT for unresectable Klatskin tumor is effective when combined neoadjuvant treatment is used and there is no acute cholangitis. However, the use of endobiliary manipulations (drainage change, EPDT) are risk factors for the development of implantation metastasis.

A cost-consequence analysis of adding pertuzumab to the neoadjuvant combination therapy in HER2-positive high-risk early breast cancer in Italy.

Clinical trials confirmed the beneficial effects of adding pertuzumab (P) to the combination of trastuzumab-chemotherapy (TC) in the (neo)adjuvant setting of high-risk HER2-positive early breast cancer (HER2+BC). We evaluated the clinical, economic and societal impact of adding pertuzumab to neoadjuvant TC combination (TPC) in Italy. A cost-consequence analysis comparing TPC vs. TC was performed developing a cohort-based multi-state Markov model to estimate the clinical, societal and economic impact of the neoadjuvant therapy of TPC versus TC in HER2+BC at high-risk of recurrence. The model works on a cycle length of 1 month and 5-years-time horizon. Literature review-based data were used to populate the model. The following clinical and economic outcomes were estimated: cumulative incidence of loco-regional/distant recurrences, life of years and QALY and both direct and indirect costs (€). Finally, sensitivity analyses were performed. TPC was associated with a 75,630 € saved of direct costs. Specifically, it was associated with an initial increase of treatment costs (+4.8%) followed by reduction of recurrence management cost (-20.4%). TPC was also associated with an indirect cost reduction of 1.40%, as well as decreased incidence of distant recurrence (-20.14%), days of work lost (-1.53%) and days lived with disability (-0.50%). Furthermore, TPC reported 10,47 QALY gained (+2.77%) compared to TC. The probability to achieve the pathological complete response (pCR) was the parameter that mostly affected the results in the sensitivity analysis. Our findings suggested that TPC combination could be a cost-saving option in patients with HER2+BC at high-risk of recurrence.

Abstract PO-002: Pembrolizumab as neoadjuvant and adjuvant therapy in combination with standard of care in resectable, locally advanced head and neck squamous cell carcinoma: Phase 3 KEYNOTE-689

Abstract PO-002: Pembrolizumab as neoadjuvant and adjuvant therapy in combination with standard of care in resectable, locally advanced head and neck squamous cell carcinoma: Phase 3 KEYNOTE-689

204. CORRELATION OF CIRCULATING T LYMPHOCYTES WITH RESPONSE TO NEOADJUVANT CHEMOIMMUNOTHERAPY IN OPERABLE ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract Background There is growing evidence indicating that neoadjuvant chemotherapy combined immune-oncology therapy (neoCTIO) with anti-PD-1 antibodies is effective in esophageal squamous cell carcinoma (ESCC). However, the precise benefits remain unclear. This study aimed to explore whether the subsets and production of effector cytokines in circulating T lymphocytes were correlated with response to neoCTIO with toripalimab in operable ESCC. Methods ESCC patients staged cT2N1–2 M0 or cT3–4aN0-2 M0, with ECOG PS 0–1 status randomly received two cycles of different sequences of toripalimab plus chemotherapy (paclitaxel and carboplatin) on day 1 to 2 of each 21-day cycle. Minimally invasive esophagectomy (MIE) was performed 4–8 weeks after neoCTIO. Peripheral blood was collected before and after neoCTIO. Flow cytometry was used to detect the effector cytokines and subsets of CD8+ and CD4+ T lymphocytes. The primary endpoints were the advanced change of subsets, effector cytokines in T lymphocytes, and pathological complete response (pCR). The secondary endpoints included major pathological response (MPR) (NCT05044728). Results 96.7% (32/33) patients received MIE with R0 resection. 18.8% (6/32) patients achieved pCR and 31.3% (10/32) patients achieved MPR. In the responders, CD8+ T lymphocytes showed higher IFNγ and TNFα coexpression compared to non-responders before neoCTIO (P = 0.010). The responders had higher frequency of effector subsets (P = 0.029) and lower naive subsets (P = 0.006) of CD8+ T lymphocytes than the non-responders before neoCTIO. No difference was found in the cell frequency of CD4+ T lymphocyte subsets between the responders and non-responders. There was no correlation between the change of subsets, effector cytokines in T lymphocytes and the sequence of neoCTIO. Conclusion NeoCTIO with toripalimab is effective in the treatment of ESCC. The baseline frequency of effector subsets and coexpression of IFNγ and TNFα in circulating CD8+ T lymphocytes have positive predictive value while the baseline frequency of Naive subsets is a negative biomarker. CD4+ T cell subsets have no correlation with the treatment response. The change of circulating CD8+ T lymphocytes is not affected by the sequence of neoCTIO.

Neoadjuvant SBRT combined with immunotherapy in NSCLC: from mechanisms to therapy.

The utilisation of neoadjuvant immunotherapy has demonstrated promising preliminary clinical outcomes for early-stage resectable non-small-cell lung cancer (NSCLC). Nevertheless, it is imperative to develop novel neoadjuvant combination therapy regimens incorporating immunotherapy to further enhance the proportion of patients who derive benefit. Recent studies have revealed that stereotactic body radiotherapy (SBRT) not only induces direct tumour cell death but also stimulates local and systemic antitumour immune responses. Numerous clinical trials have incorporated SBRT into immunotherapy for advanced NSCLC, revealing that this combination therapy effectively inhibits local tumour growth while simultaneously activating systemic antitumour immune responses. Consequently, the integration of SBRT with neoadjuvant immunotherapy has emerged as a promising strategy for treating resectable NSCLC, as it can enhance the systemic immune response to eradicate micrometastases and recurrent foci post-resection. This review aims to elucidate the potential mechanism of combination of SBRT and immunotherapy followed by surgery and identify optimal clinical treatment strategies. Initially, we delineate the interplay between SBRT and the local tumour immune microenvironment, as well as the systemic antitumour immune response. We subsequently introduce the preclinical foundation and preliminary clinical trials of neoadjuvant SBRT combined with immunotherapy for treating resectable NSCLC. Finally, we discussed the optimal dosage, schedule, and biomarkers for neoadjuvant combination therapy in its clinical application. In conclusion, the elucidation of potential mechanism of neoadjuvant SBRT combined immunotherapy not only offers a theoretical basis for ongoing clinical trials but also contributes to determining the most efficacious therapy scheme for future clinical application.

Neoadjuvant T-VEC + nivolumab combination therapy for resectable early metastatic (stage IIIB/C/D-IV M1a) melanoma with injectable disease: NIVEC trial.

9546 Background: Neoadjuvant systemic treatment with checkpoint inhibitors (ICI) has shown high response rates in patients with resectable metastasized melanoma. In patients with unresectable stage IIIB-IVA melanoma, intralesional treatment with talimogene laherparepvec (T-VEC) has also shown high and durable response rates. In this trial we investigated the safety and efficacy of neoadjuvant treatment with a combination of nivolumab and T-VEC in regionally metastasized melanoma. Methods: In this single arm phase II open-label trial (NCT04330430), 24 patients with resectable stage IIIB-IVA melanoma were included. Inclusion criteria were a RECIST 1.1 measurable lesion of ≥10mm and no prior systemic therapy. Treatment consisted of four doses of intralesional T-VEC (dose in ml according to the size of the lesions) and three doses of nivolumab 240 mg flat dose every two weeks, followed by surgery. The primary endpoint was pathological response rate according to the International Neoadjuvant Melanoma Consortium (INMC) criteria, secondary endpoints were delay or failure to perform surgery, event free survival (EFS) from time of randomization and safety. Results: Baseline characteristics are presented in the table. The overall pathological response rate was 74%, with a major pathological response (MPR = pathologic complete response (pCR) + near-pCR (max 10% viable tumor cells) in 15 patients (65%), a partial response in two patients (9%), a non-response in 4 patients (17%) and progression of disease (PD) in two patients (9%). In one patient the response was not evaluable because surgery was delayed due to a vena cava thrombosis. The two patients with PD had evidence of distant metastasis on preoperative imaging and therefore did not proceed to surgery as planned. Grade 2 treatment related adverse events (trAE) occurred in 7 patients (29%) and grade 3 in 2 (8%). There were no grade 4-5 trAEs. The 1-year EFS was 75% (95%CI 0.55-1). Conclusions: Neoadjuvant combination therapy of nivolumab and T-VEC for patients with regionally metastasized melanoma (satellite/in-transit +/- lymph node metastases) has an acceptable toxicity profile and has shown a significant major pathological response rate of 65%. Clinical trial information: NCT04330430 . [Table: see text]

Targeted Therapies and the Evolving Standard of Care for Triple-Negative and Germline BRCA1/2-Mutated Breast Cancers in the High-Risk, Early-Stage Setting.

Immune checkpoint inhibitors (ICIs) and poly (ADP-ribose) polymerase (PARP) inhibitors have transformed the treatment landscape of metastatic triple-negative breast cancer (TNBC). Trial results have demonstrated the clinical benefit of these targeted agents in the advanced TNBC setting and have led to their evaluation in the treatment of high-risk, early-stage TNBC and BRCA-mutated breast cancer. We provide a summary of the results that have led to the establishment of the ICI pembrolizumab and the PARP inhibitor olaparib as new standards of care. Using PubMed, we searched for original articles published in English between 2017 and 2022. Search terms included triple-negative breast cancer, adjuvant, neoadjuvant, immunotherapy, and PARP inhibitors. Two targeted therapies have been approved by the US Food and Drug Administration for the treatment of TNBC and BRCA-mutated breast cancers in the high-risk, early-stage setting on the basis of clinical trial results demonstrating improved clinical outcomes. For high-risk, early-stage TNBC, pembrolizumab was approved as neoadjuvant therapy in combination with chemotherapy and as a single agent for continued treatment after surgery; this approval was based on results of the KEYNOTE-522 trial. Olaparib was approved for the adjuvant treatment of patients with high-risk, early-stage human epidermal growth factor receptor type 2 (HER2)-negative breast cancer with germline BRCA1/2 mutations who have been previously treated with neoadjuvant or adjuvant chemotherapy on the basis of the OlympiA trial results. Clinical trial results demonstrate the pronounced clinical benefits of pembrolizumab combined with chemotherapy for high-risk, early-stage TNBC and adjuvant olaparib for high-risk, early-stage HER2-negative BRCA1/2-mutated breast cancer.

Neoadjuvant Androgen Receptor Signaling Inhibitors before Radical Prostatectomy for Non-Metastatic Advanced Prostate Cancer: A Systematic Review.

(1) Background: Several phase II studies, including randomized controlled trials (RCTs), assessed the efficacy of adding androgen receptor signaling inhibitors (ARSIs) to androgen deprivation therapy (ADT) as a neoadjuvant treatment in patients treated with radical prostatectomy (RP) for prostate cancer (PCa). Summarizing the early results of these studies could help in designing phase III trials and patient counseling. (2) Methods: We queried three databases in January 2023 for studies that included PCa patients treated with neoadjuvant ARSI-based combination therapy before RP. The outcomes of interest were oncologic outcomes and pathologic responses, such as pathologic complete response (pCR) and minimal residual disease (MRD). (3) Results: Overall, twenty studies (eight RCTs) were included in this systematic review. Compared to ADT or ARSI alone, ARSI + ADT was associated with higher pCR and MRD rates; this effect was less evident when adding a second ARSI or chemotherapy. Nevertheless, ARSI + ADT resulted in relatively low pCR rates (0-13%) with a high proportion of ypT3 (48-90%) in the resected specimen. PTEN loss, ERG positive, or intraductal carcinoma seem to be associated with worse pathologic response. One study that adjusted for the effects of possible confounders reported that neoadjuvant ARSI + ADT improved time to biochemical recurrence and metastasis-free survival compared to RP alone. (4) Conclusions: Neoadjuvant ARSI + ADT combination therapy results in improved pathologic response compared to either alone or none in patients with non-metastatic advanced PCa. Ongoing phase III RCTs with long-term oncologic outcomes, as well as biomarker-guided studies, will clarify the indication, oncologic benefits, and adverse events of ARSI + ADT in patients with clinically and biologically aggressive PCa.

Incidence and Risk of Venous Thromboembolism in Patients With Resectable Pancreatic Cancer Receiving Neoadjuvant Chemotherapy.

Pancreatic cancer has the highest risk of venous thromboembolism (VTE). Additionally, chemotherapy for cancer patients increases the risk of developing VTE. Due to recent advances in neoadjuvant chemotherapy (NAC) regimens, more patients with resectable pancreatic cancer will receive NAC. However, the incidence, risk, and predictors of developing VTE in these patients have not been fully evaluated. We retrospectively evaluated the incidence, risk, and predictors of VTE among 67 consecutive patients with resectable pancreatic cancer who received neoadjuvant combination therapy with gemcitabine+S-1 (NAC-GS) followed by surgery and 45 patients with resectable pancreatic cancer who underwent upfront surgery (Up-S). The incidence of VTE in the NAC-GS and Up-S groups was 10.4% and 6.6%, respectively. Preoperative D-dimer levels were significantly higher in the NAC-GS group, and D-dimer levels were significantly increased during NAC-GS. Preoperative D-dimer level was the only predictor for VTE in patients with resectable pancreatic cancer who received NAC-GS. There is an increased risk of developing VTE during NAC. Screening with D-dimer and taking appropriate measures to suppress critical VTE is essential to provide NAC to patients with resectable pancreatic cancer.

The effect of gastric fundus radiation dose on postoperative anastomotic leakage in esophageal cancer.

Standard-of-care treatment for locally advanced esophageal carcinoma (LAEC) includes neoadjuvant chemoradiotherapy followed by esophagectomy. A potentially catastrophic surgical complication is the development of a postoperative anastomotic leak. To date, the association with radiation dose exposure had been inconclusive. We examined the correlation between radiation exposure to the gastric fundus and risk of postoperative leakage using contemporary radiation doses and fractionation. A total of 69 consecutive patients with LAEC who underwent neoadjuvant chemoradiotherapy followed by esophagectomy in our tertiary center were prospectively followed (median, 27 months). Neoadjuvant regimen included 50.4 Gy in 28 fractions with 5-fluorouracil and cisplatin and 41.4 Gy in 23 fractions with carboplatin and paclitaxel. The gastric fundus was contoured and dosimetric and radiation technique parameters were retrospectively evaluated. Of the total number of patients, 71% and 29% had esophageal and gastroesophageal junction (GEJ) tumors, respectively. Fourteen patients (20.3%) experienced anastomotic leaks within a median of 2 days postoperatively, 78.6% of whom had lower third esophagus or GEJ primaries. Mean and minimum fundus dose did not significantly differ between those with and those without leakage (p = 0.42, p = 0.51). Mean fundus V25, V30, and V35 doses were numerically but not statistically higher in those with anastomotic leak (p = 0.58, p = 0.39, and p = 0.30, respectively). No correlation with incidence of leakage was seen between 3D and IMRT treatment modalities. In our comparatively large prospectively collected series of patients treated for LAEC, radiation dose to the gastric fundus during neoadjuvant combination therapy prior to surgery did not correlate with the risk of postoperative anastomotic leak.