neoadjuvant or adjuvant chemotherapy

Overview

Neoadjuvant or adjuvant chemotherapy refers to systemic anticancer drug treatment given either before definitive local therapy (neoadjuvant chemotherapy) or after surgery or other primary treatment (adjuvant chemotherapy). In oncology, these approaches are used to reduce tumor burden, improve resectability, eradicate micrometastatic disease, and improve long-term disease control. Their use is highly disease-specific and depends on tumor biology, stage, patient fitness, and the planned local treatment strategy.

Biologically, neoadjuvant chemotherapy can also serve as an in vivo test of treatment sensitivity, allowing assessment of pathologic response such as complete pathologic response. Adjuvant chemotherapy is intended to eliminate residual microscopic disease after resection. Recent studies have examined these strategies across breast cancer, pancreatic cancer, gastric cancer, colorectal cancer, rectal cancer, sarcoma, bladder cancer, osteosarcoma, and male breast cancer, often in combination with agents such as pembrolizumab, durvalumab, serplulimab, oxaliplatin, fluorouracil, capecitabine, cyclophosphamide, and cisplatin. Related research has also explored interactions with immune microenvironments, including tertiary lymphoid structures, B-cell populations, and CD8+ S100B+ T cells, as well as resistance mechanisms involving cancer-associated fibroblast biology and oxidative stress pathways.

Focus of Latest Publications

Recent publications show that neoadjuvant or adjuvant chemotherapy remains an active area of clinical and translational research across multiple tumor types.

In localized pancreatic cancer, a nationwide analysis evaluated how age influenced quality of life, 90-day mortality, adjuvant chemotherapy use, and overall survival after different treatment strategies. A related pancreatic study examined primary pancreatic fibroblasts derived from neoadjuvant chemotherapy-treated versus treatment-naïve pancreatic ductal adenocarcinoma, indicating that neoadjuvant exposure may alter the tumor stromal compartment and proteomic profile. Another pancreatic paper assessed preoperative serum total cholesterol as a predictor of adjuvant chemotherapy completion after pancreaticoduodenectomy, emphasizing that completion of postoperative therapy is a key determinant of long-term survival.

In gastric cancer, a phase 3 randomized study compared perioperative serplulimab plus neoadjuvant chemotherapy with perioperative chemotherapy alone in PD-L1-positive, locally advanced, resectable gastric or gastro-oesophageal junction adenocarcinoma. This trial specifically paired serplulimab with S-1 plus oxaliplatin in the neoadjuvant phase and then continued serplulimab or chemotherapy postoperatively, reflecting the growing integration of immunotherapy with perioperative chemotherapy.

In breast cancer, several studies focused on neoadjuvant chemotherapy in early-stage disease, including human epidermal growth factor receptor 2-positive and triple-negative breast cancer. One long-term analysis from the GeparNuevo trial evaluated durvalumab added to neoadjuvant chemotherapy in early triple-negative breast cancer and investigated whether this improved pathologic complete response and survival. Another multi-institution study examined predictors of pathologic complete response in early-stage triple-negative breast cancer treated with neoadjuvant chemo-immunotherapy, referencing the KEYNOTE-522 regimen in which pembrolizumab was added to neoadjuvant chemotherapy and improved pCR and overall survival. Additional work assessed early tumor size changes during neoadjuvant chemotherapy as a predictor of pathologic response, and another study compared survival after neoadjuvant versus adjuvant chemotherapy in cT1-2N0M0 triple-negative breast cancer, noting that the relative benefit of postoperative therapy after neoadjuvant treatment remains uncertain. A retrospective cohort study in male breast cancer also addressed the unclear survival benefit of neoadjuvant chemotherapy and the difficulty of defining which patients benefit most. Another study examined racial differences in pCR and clinical outcomes after neoadjuvant chemotherapy, while a separate analysis explored whether postmastectomy radiotherapy may benefit patients who were clinically node-positive but became ypN0 after neoadjuvant chemotherapy. Exercise adherence during (neo-)adjuvant chemotherapy was also studied in Swedish breast cancer patients, highlighting supportive care during treatment.

In colorectal and rectal cancer, neoadjuvant chemotherapy was investigated in several contexts. A randomized phase 2 trial tested mFOLFOXIRI with or without cadonilimab versus mFOLFOX6 in locally advanced colorectal cancer, reflecting interest in combining chemotherapy with dual immune checkpoint blockade. Another study examined total neoadjuvant therapy versus neoadjuvant chemotherapy alone for high-risk locally advanced rectal cancer, noting that guideline-recommended total neoadjuvant therapy remains controversial in some populations because of radiotherapy-related adverse effects. Additional translational work showed that quiescent persister tumor cells are enriched after neoadjuvant chemotherapy in colorectal cancer, and that T cell surveillance and CD155-CD96 signaling may help control these resistant cells. A separate study on liver metastasis from colorectal cancer reported randomized long-term results comparing hepatectomy followed by mFOLFOX6 with hepatectomy alone, directly addressing the role of adjuvant chemotherapy after metastasectomy.

In sarcoma, a real-world economic evaluation from the French DEEPSARC study assessed adjuvant chemotherapy for non-metastatic sarcoma, noting that its survival benefit remains debated. In osteosarcoma, machine learning with clinical data and MRI radiomics was used to predict resistance to neoadjuvant chemotherapy, with histological response as the reference standard. In bladder cancer, chemotherapy-induced anemia was evaluated as a prognostic factor in patients treated with neoadjuvant cisplatin-based chemotherapy and cystectomy, underscoring treatment-related toxicity as a clinically relevant outcome.

Several studies addressed broader perioperative treatment questions. In high-risk locally advanced rectal cancer, total neoadjuvant therapy was compared with neoadjuvant chemotherapy alone. In pancreatic cancer, adjuvant chemotherapy completion and age-related outcomes were studied in relation to survival. In colorectal cancer, chemoport-related right innominate vein stenosis was analyzed with respect to treatment setting, with lower event-free probability in palliative chemotherapy than in adjuvant chemotherapy. Across these studies, adjuvant chemotherapy was repeatedly framed as a key component of curative-intent treatment, while neoadjuvant chemotherapy was used to improve surgical outcomes, assess response, and guide escalation or de-escalation of therapy.

Key Publications

• NEWJun The impact of age on quality of life, 90-day mortality, adjuvant chemotherapy, and survival after treatment for localized pancreatic cancer: A nationwide analysis. (European journal of cancer (Oxford, England : 1990), 2026, PMID 42208281): "adjuvant chemotherapy use and OS after various treatment strategies between elderly and younger patients with localized pancreatic cancer."
• Jun Spatial multi-omics implicate the interaction between Tpex and B cells in tertiary lymphoid structures after neoadjuvant therapy. (Cancer discovery, 2026, PMID 42339989): "Tertiary lymphoid structures (TLSs) are associated with the efficacy of various oncological therapies."
• Jun Economic evaluation of adjuvant chemotherapy for non-metastatic sarcoma using the real-world data from the French nationwide DEEPSARC study. (Journal of medical economics, 2026, PMID 42334926): "The efficacy of adjuvant chemotherapy (AC) in improving survival for patients with sarcoma is debated."
• Jun Perioperative serplulimab with neoadjuvant chemotherapy versus perioperative chemotherapy in PD-L1-positive gastric cancer (ASTRUM-006): a randomised, double-blind, multicentre, phase 3 study. (Lancet (London, England), 2026, PMID 42225112): "We evaluated the efficacy and safety of neoadjuvant serplulimab with S-1 plus oxaliplatin (SOX) chemotherapy followed by adjuvant serplulimab versus neoadjuvant placebo plus SOX followed by adjuvant SOX in patients with PD-L1-positive, locally advanced, resectable gastric or gastro-oesophageal junction adenocarcinoma."
• Jun Heteronemin suppresses chemoresistant oral squamous cell carcinoma cells through ROS-mediated apoptosis and cuproptosis-associated mitochondrial stress. (Apoptosis : an international journal on programmed cell death, 2026, PMID 42315805): "Additionally, HET increased reactive oxygen species (ROS) production, whereas ROS scavenger N-acetylcysteine (NAC) attenuated HET-induced apoptosis and restored cuproptosis-related markers."
• Jun Coexposure to heat stress and polystyrene nanoplastics induces neuroinflammation and cognitive impairment via oxidative stress-NLRP6-pyroptosis axis. (Journal of hazardous materials, 2026, PMID 42030847): "The administration of the antioxidant N-acetylcysteine (NAC) attenuated these pathological alterations by suppressing oxidative damage, thereby rescuing cognitive performance."
• Jun Proteomic characterization of primary pancreatic fibroblasts derived from neoadjuvant chemotherapy treated versus treatment-naïve PDAC. (Journal of proteomics, 2026, PMID 42025917): "Neoadjuvant chemotherapy (NAT) is increasingly used in the treatment of pancreatic ductal adenocarcinoma (PDAC)."
• Jun Neoadjuvant mFOLFOXIRI with or without cadonilimab versus mFOLFOX6 in locally advanced colorectal cancer: A randomized phase 2 trial (OPTICAL-2). (Med (New York, N.Y.), 2026, PMID 42134324): "The efficacy of neoadjuvant chemotherapy combined with dual immune checkpoint blockade in proficient mismatch repair/microsatellite-stable (pMMR/MSS) locally advanced colorectal cancer (LACRC) remains uncertain."
• Jun Durvalumab in Combination With Neoadjuvant Chemotherapy in Early Triple-Negative Breast Cancer: Long-Term Analysis From the GeparNuevo Trial. (Journal of clinical oncology : official journal of the American Society of Clinical Oncology, 2026, PMID 42008768): "The phase II GeparNuevo trial investigated whether adding durvalumab to neoadjuvant chemotherapy (NACT) only in patients with early triple-negative breast cancer cT1b-cT4a-d would improve pathologic complete response (pCR) rate and patient survival."
• Jun Dietary Supplementation with N-Acetylcysteine Ameliorates Sleep Deprivation-Induced Ruminal Apoptosis in Tibetan Sheep. (Journal of agricultural and food chemistry, 2026, PMID 42150772): "This study revealed that N-acetylcysteine (NAC), a naturally occurring antioxidant in Allium plants with antioxidant properties, ameliorates SD-induced ruminal microbiota dysbiosis, lipopolysaccharide (LPS) leakage, and apoptosis in sheep."