Radiography · Referral letter · Intermediate

Radiography — Referral for a CT Abdomen in a Patient with Unexplained Weight Loss

A GP registrar refers a 66-year-old man for urgent CT abdomen and pelvis investigation of unexplained weight loss, abdominal pain, and a significantly elevated CEA level. This intermediate case requires selecting the relevant clinical findings that justify urgent imaging while cutting the extensive social and family history.

Letter type

Referral

Write to

Radiologist

Target length

180–200 words

The case notes

Patient: Mr Colin Brady, 66 years old; retired postal worker

Presenting complaint: Unexplained weight loss 8 kg over 3 months; dull periumbilical pain (NRS 3/10); change in bowel habit — looser stools for 6 weeks; reduced appetite

Examination: Mild periumbilical tenderness on palpation; no palpable mass; no hepatomegaly; no jaundice; no lymphadenopathy

Investigations: CEA 18.5 ng/mL (significantly elevated; normal <5); FBC: mild anaemia (Hb 108 g/L, MCV 74 — microcytic); CRP 22 (mildly elevated)

Bowel history: No previous colonoscopy; no family history of bowel cancer (patient knows); not on aspirin or NSAIDs; last bowel cancer screening FIT test negative (3 years ago)

Social history: Non-smoker; drinks 12 units/week; wife reports he has seemed fatigued and uncharacteristically anxious

Requested investigation: Urgent CT abdomen and pelvis with contrast — to investigate for possible colorectal malignancy or other abdominal pathology causing the weight loss, CEA elevation, and anaemia

Task: Write a referral letter to the radiology department requesting the CT scan, providing the clinical information needed to prioritise the request and conduct the study safely.

Writing task

Write a referral letter to the radiology department requesting the CT scan, providing the clinical information needed to prioritise the request and conduct the study safely.

What to include, what to cut

The hardest mark to win is selection. The same case notes contain decision-relevant facts and distractors. Here is what an examiner expects to see in a Grade B letter for this scenario, and what should be left out.

Include

  • Weight loss 8 kg over 3 months, change in bowel habit, and microcytic anaemia — together

    These three findings together constitute the red-flag cluster for colorectal cancer under NICE urgent referral guidance. The radiologist needs to understand the clinical urgency is based on a symptom cluster, not just one finding.

  • CEA 18.5 ng/mL significantly elevated (normal <5)

    A markedly elevated CEA in the context of weight loss, anaemia, and change in bowel habit is the single most important investigation result that upgrades this to urgent. The radiologist uses this to triage the imaging request.

  • That the scan is requested with contrast and the clinical question being asked

    The radiologist must know whether to use contrast and what clinical question to address. 'CT abdomen and pelvis with IV contrast to investigate for possible colorectal or other abdominal malignancy' is the minimum specification.

Leave out

  • The social history and the wife's observations

    Not relevant to the radiology request. The radiologist does not use alcohol consumption or the wife's concerns to conduct or report the CT scan.

  • The negative FIT test from 3 years ago

    A point of historical context, but a negative FIT 3 years ago does not reduce the urgency of a current CEA of 18.5 with red-flag symptoms. Including it risks being read as a reason to downgrade urgency, which is the opposite of the clinical intent.

Criterion in focus · Purpose

A radiology referral letter must state the clinical question, not just the test requested. 'Please arrange CT abdomen' is incomplete; 'CT abdomen and pelvis with IV contrast to investigate for possible colorectal malignancy in the context of unexplained weight loss, elevated CEA (18.5), and microcytic anaemia' is the professional standard. The radiologist uses the clinical question to determine the scan protocol and to frame their report.

Now write the letter — and find out what is blocking your Grade B

Write a 180–200 words referral letter from these notes, paste it into the free checker for an instant read, then submit it for a human grade against all six criteria. Dr Mariam's team returns line-by-line feedback, from $12.

Questions about this case note

What clinical information must a CT scan referral letter include?
Six items: (1) the specific scan requested with the region (CT abdomen and pelvis), (2) whether contrast is required and the type (IV, oral), (3) the clinical question being asked, (4) the red-flag findings that justify urgency, (5) any allergy or contraindication to contrast, (6) renal function if IV contrast is used. A referral missing the clinical question or the urgency justification will be rescheduled or down-triaged by the radiology team.
Should I include a differential diagnosis in a radiology referral letter?
The primary clinical question is sufficient: 'investigate for possible colorectal malignancy or other abdominal pathology.' Listing every differential diagnosis is not required and can lengthen the letter without adding value. The radiologist will consider all possibilities during reporting — your job is to define the clinical priority.

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