The ESMO annual meeting 2021 will probably be remembered as one of the first post-pandemic ‘hybrid’ meetings: approximately half of the speakers and moderators were able to attend in person, while the rest contributed virtually. Despite some technical difficulties, the format was largely a success. The physical presence of other speakers made for livelier and sometimes more jovial discussion sessions, while those who were unable to attend, either owing to travel restrictions or personal choice, were still able to contribute. This format, perhaps with additional attendance from a limited number of non-speakers, is likely to be adopted by future meetings as travel restrictions are slowly eased.

This year’s Presidential sessions did not disappoint. Perhaps most notably, DESTINY-Breast03 revealed a dramatic improvement in progression-free survival with trastuzumab deruxtecan relative to trastuzumab emtansine in patients with metastatic HER2-positive breast cancer, with a much lower risk of interstitial lung disease relative to later-line settings. Although differences in overall survival were not statistically significant at this time point, the magnitude of benefit suggests a considerable improvement. These data identify a new second-line therapy in this setting, and arguably indicate a need for testing in the first line.

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Among others, practice-changing new data were presented on the role of combination therapies including novel anti-androgen therapies in men with high-risk non-metastatic (STAMPEDE) and castration-sensitive (PEACE-1) prostate cancer; on the role of sunitinib in patients with progressive phaeochromocytomas or paragangliomas (FIRSTMAPPP); and from the KEYNOTE-826 study, on the addition of pembrolizumab to chemotherapy for women with persistent, recurrent or metastatic cervical cancer. Furthermore, novel data on the ability of patients with cancer to develop an immune response following vaccination against COVID-19 (CAPTURE and VOICE) will provide reassurance to most patients and their clinicians.

Prominent data on the role of immune-checkpoint inhibitors in the adjuvant setting were also a feature of this year’s Presidential sessions. The presentation of data on the role of pembrolizumab in patients with high-risk stage II melanoma (KEYNOTE-716) was followed by a lively debate. Data from IMPower 010, a phase III trial exploring the role of atezolizumab after adjuvant chemotherapy for patients with stage I–IIIa non-small-cell lung cancer, proved similarly worthy of discussion. Data from these trials are likely to inform future clinical practice, although, as a minimum, longer follow-up monitoring will be needed.

Outside of the Presidential sessions, this year’s meeting will be remembered for the abundance of data on novel therapies for women with metastatic cervical cancer, a lethal but nonetheless historically overlooked cancer with little change in the standard-of-care for many years. In addition to KEYNOTE-826, early data were also provided for the novel anti-PD-1/anti-CTLA-4 combination of balstilimab plus zalifrelimab (NCT03495882), bintrafusp-α, a bifunctional fusion protein targeting PD-L1 and TGFβ in HPV-positive tumours including cervical cancer (INTR@PID 001, study 012) and combinations involving the antibody–drug conjugate tisotumab vedotin (ENGOT-Cx8/GOG-3024/innovaTV 205). The latter received FDA Accelerated Approval as monotherapy for recurrent and/or metastatic cervical cancer during the meeting.

Other notable findings included long-awaited evidence that hyperthermic intraperitoneal chemotherapy can improve survival outcomes in patients with complete cytoreduction of peritoneal metastases from gastric cancer (GASTRIPEC-I) and the demonstration of objective responses in almost half of all patients with advanced-stage gastrointestinal cancers receiving anti-claudin 18.2 CAR T cells in a phase I trial (CT041-CG4003).

Despite much excitement over the many advances in novel therapies reported throughout the meeting, a session on access to cancer drugs provided a sobering finale: patients in only 46% of high-income countries will have access to novel cancer therapies 5 years after regulatory approval, and for lower-income countries, this percentage is much lower. Thus, improvements in access to existing standards-of-care are needed just as much as novel therapies themselves.