Immunotherapy and chemotherapy in oesophageal cancer: what changed

Updates on immunotherapy combined with chemotherapy for esophageal cancer have changed the treatment conversation for people with advanced disease. Medicines that help the immune system recognise tumour cells are now being studied and used alongside platinum-based chemotherapy, rather than being reserved only for later lines of treatment.

The strongest evidence has emerged in unresectable or metastatic oesophageal squamous cell carcinoma, with additional progress in adenocarcinoma and gastro-oesophageal junction cancers. For Australian clinicians, treatment decisions depend on tumour type, PD-L1 results, fitness for therapy, prior treatment, Therapeutic Goods Administration (TGA) approval and Pharmaceutical Benefits Scheme (PBS) access.

Why combination treatment matters

Chemotherapy can reduce tumour bulk quickly, while checkpoint inhibitors such as nivolumab and pembrolizumab restore part of the immune response against cancer. Combining these approaches may produce deeper or longer-lasting control than chemotherapy alone in selected patients.

The benefit is not uniform across every oesophageal cancer. Squamous cell carcinoma, which is more common in parts of Asia and remains an important presentation in Australia, has generated particularly compelling trial results. Adenocarcinoma often requires a different biomarker and treatment discussion, especially when the tumour begins near the gastro-oesophageal junction.

Findings from major clinical trials

The CheckMate 648 trial compared chemotherapy alone with nivolumab plus chemotherapy, and also with nivolumab plus ipilimumab, in advanced oesophageal squamous cell carcinoma. Nivolumab with chemotherapy improved overall survival and progression-free survival in key analysis groups, including people whose tumours had a PD-L1 combined positive score (CPS) of at least 1.

KEYNOTE-590 evaluated pembrolizumab with cisplatin and fluoropyrimidine chemotherapy in advanced oesophageal cancer and gastro-oesophageal junction cancer. The combination improved survival, with a clearer signal in patients with a PD-L1 CPS of 10 or higher and in squamous cell carcinoma. These findings helped move immunotherapy from an experimental option towards a first-line consideration.

Biomarkers guide the conversation

PD-L1 testing is central, but it is not a simple yes-or-no predictor. The CPS counts PD-L1 staining in tumour and immune cells relative to the total number of viable tumour cells. Different trials and jurisdictions use different thresholds, so a result must be interpreted alongside the treatment indication.

Testing may also include HER2 status in adenocarcinoma or gastro-oesophageal junction disease, mismatch repair proteins and microsatellite instability. MSI-high or mismatch repair-deficient tumours are uncommon in oesophageal cancer but may be especially sensitive to immune checkpoint blockade. A pathology review at a specialist centre can be useful when tissue is limited or results are uncertain.

Treatment delivery and monitoring

Combination treatment is generally given in cycles, with intravenous chemotherapy and immunotherapy scheduled according to the selected protocol. Before each cycle, the team usually reviews blood counts, kidney and liver function, weight, nutrition, swallowing symptoms and performance status.

Immune-related adverse effects can affect the skin, bowel, lungs, liver, thyroid or other endocrine organs. New diarrhoea, breathlessness, jaundice, severe rash, marked fatigue or headaches should be reported promptly. These problems differ from typical chemotherapy effects and may require corticosteroids or a treatment pause rather than simply adjusting a chemotherapy dose.

Balancing benefit, risk and quality of life

A longer survival estimate is important, but so are swallowing ability, pain, weight maintenance and the capacity to remain at home. Oesophageal cancer can cause malnutrition quickly, making input from a dietitian, speech pathologist, gastroenterologist and palliative care team valuable from the beginning.

Combination therapy can bring additional toxicity, cost and appointment demands. Older age alone does not rule out treatment, although frailty, autoimmune disease, organ dysfunction and concurrent medicines may change the risk profile. Shared decisions should cover the likely benefit, alternatives and what happens if the cancer progresses.

How this fits Australian practice

In Australia, the pathway commonly starts with a GP referral to a public or private multidisciplinary team, followed by endoscopy, staging scans and biopsy-based molecular testing. Specialists at centres such as Peter MacCallum Cancer Centre in Melbourne, Royal Brisbane and Women’s Hospital, or major Sydney cancer services may discuss complex cases with regional hospitals through multidisciplinary meetings and telehealth.

TGA registration and PBS listing are separate questions, and funding criteria can change. A medicine may have regulatory approval yet still involve private payment, a clinical trial or a different funded indication. Patients in regional Western Australia, Queensland or the Northern Territory may also face long travel for infusions, pathology review and urgent toxicity assessment, making local shared-care arrangements especially important.

What patients and clinicians should take forward

The most useful update is that immunotherapy plus chemotherapy is now a biomarker-informed first-line strategy for some people with advanced oesophageal cancer, rather than a single treatment suitable for everyone. Histology, PD-L1 CPS, HER2 and MSI status should be reviewed before the regimen is selected.

For practical decision-making, confirm the pathology, ask which trial evidence matches the tumour type, check current TGA and PBS requirements, and establish who to contact about immune-related symptoms. The best treatment plan is one that combines evidence-based cancer control with realistic support for nutrition, travel, work and daily life.