FRCR VAULT
Miscellaneous18 July 2026

FRCR Part 2A (CO2A): the complete guide

If you are an ST registrar in clinical oncology working out when to sit CO2A, how it is structured, or what you are actually eligible for, the honest answer is that the Royal College of Radiologists' own pages are scattered across several URLs and none of them tell the whole story on their own. This guide pulls the exam structure, 2026 dates, eligibility rules and curriculum organisation into one place, with every claim traceable back to the RCR page it came from.

What CO2A is and where it sits in the FRCR sequence

The Royal College of Radiologists runs three clinical oncology exams in sequence. The First FRCR (CO1) comes first, and "expects candidates to have acquired a broad knowledge of those subjects that relate to the investigation and management of patients with cancer." CO2A — the Final FRCR (Part A) — follows, and "expects candidates to have a wide knowledge of malignant disease and the management of patients with cancer," with "the main emphasis... on radiotherapy and drug therapy," alongside "a good knowledge of general medicine, surgery and gynaecology." CO2B, the Final FRCR (Part B), comes last and tests the same breadth of knowledge in a different assessment format. The RCR notes that "candidates wishing to attempt the associated CO2B exam should make a booking for this at the same time" as CO2A, so it is worth planning both sittings together rather than treating CO2A as a standalone hurdle.

Exam structure

CO2A is examined against the specialty training curriculum for clinical oncology, and the format is fixed: two papers, each of 120 single best answer (SBA) questions, giving 240 SBAs across the whole exam. Each question has a stem — a question or statement — and five answer options. Candidates get three hours to answer the 120 questions in each session. Marking is straightforward: one mark for each item correctly answered, zero for each incorrect answer, and the exam is not negatively marked, so there is no penalty for a guess over leaving a question blank.

The two sessions are not randomly mixed. Session 1 covers respiratory, urology, head and neck, skin, CNS and gynaecological tumours. Session 2 covers breast, upper and lower gastrointestinal, haematological malignancy, radiology and imaging, and a miscellaneous group spanning paediatric oncology, thyroid cancer, sarcoma, acute oncology and carcinoma of unknown primary. If you know this split going in, you can pace your revision so that no tumour site is a surprise on the day, and you can choose to sit past papers or practice sets in the same session-shaped blocks you will meet on exam day.

The exam runs "twice a year: normally in February and August/September."

2026 sitting dates and booking windows

Two sittings are confirmed for 2026. The February 2026 session sat on Thursday 12 February 2026, with resident doctor and RCR member bookings opening Monday 29 September 2025, non-member bookings opening Monday 6 October 2025, the booking window closing Friday 28 November 2025, and results published Thursday 5 March 2026.

The next sitting is the August 2026 session, on Thursday 27 August 2026. Resident doctor and member bookings opened Monday 17 November 2025, non-member bookings opened Monday 24 November 2025, and the booking window closed Friday 26 June 2026, with results due Thursday 17 September 2026. If you are reading this after 26 June 2026, that window has already closed — the practical lesson is that RCR booking windows close roughly two months before the sitting itself, so check the current CO2A page as soon as you are thinking about a sitting rather than a few weeks before it, and diarise the booking window the moment it is published.

Fees vary by venue and RCR membership status. For UK venues (Belfast, Bridgend, Edinburgh, Leeds and London), the fee is £576–£663 for members and £882 for non-members. Overseas venues cost more: Hong Kong is £819 for members and £1,090 for non-members, and Kolkata, India is £730 for members and £972 for non-members. Confirm current fees on the RCR site before booking, as these figures are a snapshot of what was published for the 2026 cycle.

Eligibility

CO2A eligibility has two parts. First, you must have already passed the First FRCR exam. Second, you need a minimum of three years of supervised clinical oncology training covering the exam syllabus. The RCR allows a narrow exception to the second requirement: "in exceptional circumstances, with support from the Training Programme Director and at the discretion of the Medical Director (Education and Training), this minimum training period may be reduced to two years and six months." That route is discretionary and needs your TPD's backing — it is not something to assume you qualify for without asking early.

Attempts are capped. "Candidates are permitted six attempts at Part A exam. In order to attempt this exam for a seventh, or further, time candidates will have to demonstrate additional educational experience." This cap is shared across RCR exams generally, in line with GMC expectations, so it is worth treating each sitting as a real attempt rather than a low-stakes trial run.

The curriculum and its tumour-site organisation

CO2A questions are drawn against the specialty training curriculum for clinical oncology, which "defines the generic and specialty-specific capabilities required to achieve a certificate of completion of training (CCT)" and is built to prepare trainees to "manage cancer across a wide range of tumour types and through the full disease pathway." In practice, for exam preparation, the session split described above is the more actionable version of this: session 1's six tumour groups and session 2's five groups (including the miscellaneous cluster) map directly onto how the paper is built, so a revision plan organised the same way — one tumour site or group at a time, radiotherapy and systemic therapy together — mirrors how you will actually be tested.

How to prepare

There is no shortcut around the breadth of CO2A: two full SBA papers covering eleven tumour groups plus imaging means you cannot cram a single subsite and expect to pass. A few practical points follow from the exam's own structure rather than folklore:

  • Work session by session. Since the two papers are split cleanly by tumour group, block your revision the same way — do not leave one whole session's worth of sites until the final fortnight.
  • Treat "no negative marking" as permission to answer everything, not as permission to guess blind. Work through five plausible options and commit to a best answer even when unsure, since a blank answer and a wrong guess score identically.
  • Use single-best-answer practice, not recall lists. The exam format rewards the ability to weigh five plausible-sounding options against each other, which is a different skill from recognising a fact in isolation. Timed SBA practice with per-option feedback — explaining why each distractor is wrong, not just which answer is right — builds that skill faster than reading alone. This is the gap cited-question banks such as FRCR Vault are built to fill, alongside past papers and RCR sample questions.
  • Book early and plan CO2B alongside CO2A if you intend to sit both, since the RCR explicitly invites booking them together.
  • Confirm your eligibility with your Training Programme Director well before the booking window opens, particularly if you are considering the reduced 2 years 6 months route — this needs sign-off, not just a personal calculation of your training time.

Common pitfalls

Registrars preparing for CO2A tend to fall into a small number of avoidable traps. The most common is uneven revision: focusing on a comfortable subsite (often the trainee's own subspecialty interest) at the expense of a session-2 group like haematological malignancy or the miscellaneous cluster, which is easy to underweight precisely because it spans several small topics rather than one large one. A second is under-practising imaging and general medicine/surgery content, on the assumption that CO2A is purely a radiotherapy and systemic therapy exam — the RCR's own description explicitly includes "general medicine, surgery and gynaecology" alongside radiotherapy and drug therapy. A third is leaving the booking window until late; since it closes around two months before the sitting and not all fee bands are identical across venues, a missed deadline can mean waiting a further six months for the next sitting. Finally, because the exam is not negatively marked, leaving questions unanswered under time pressure in the final minutes of a session is a pure loss — mark something for every stem before time runs out.

If you want cited single-best-answer practice with per-option feedback organised by tumour site, that is what FRCR Vault is built for. Details on access are on the pricing page.

References

Educational content for FRCR 2A revision only, not medical advice. Clinical decisions belong with the treating team and current local protocols.