What initial investigations should I consider for a patient presenting with unintentional weight loss?

Initial investigations for a patient presenting with unintentional weight loss should be tailored based on age, symptoms, and risk factors to identify possible underlying cancers or other serious conditions.

• General assessment: Carry out a thorough clinical assessment for additional symptoms, signs, or findings to clarify the most likely cause, including cancer.
• Colorectal cancer suspicion: For unexplained weight loss with abdominal pain (age 40 and over), rectal bleeding (adults under 50), or age 50 and over, offer quantitative faecal immunochemical testing (FIT).
• Lung or mesothelioma suspicion: For patients aged 40 and over who have ever smoked, or those exposed to asbestos, or with symptoms such as cough, fatigue, shortness of breath, chest pain, or appetite loss, offer an urgent chest X-ray to be done within 2 weeks.
• Oesophageal or stomach cancer suspicion: For weight loss with upper abdominal pain, reflux, or dyspepsia in those aged 55 and over, refer urgently via a suspected cancer pathway. Consider non-urgent direct access upper gastrointestinal endoscopy if there is raised platelet count or nausea/vomiting in those 55 and over.
• Ovarian cancer suspicion: In women aged 18 and over with unexplained weight loss, consider measuring serum CA125 in primary care.
• Pancreatic cancer suspicion: For weight loss with diarrhoea, back pain, abdominal pain, nausea, vomiting, constipation, or new-onset diabetes in those aged 60 and over, consider an urgent direct access CT scan within 2 weeks, or urgent ultrasound if CT is unavailable.
• Lymphoma suspicion: Weight loss with unexplained splenomegaly or lymphadenopathy in adults should prompt consideration of a suspected cancer pathway referral.

Summary: Initial investigations include quantitative faecal immunochemical testing, urgent chest X-ray, serum CA125 measurement, urgent CT or ultrasound scans, and consideration of urgent referrals for endoscopy or cancer pathways depending on associated symptoms and patient demographics.

These recommendations are based on the NICE guideline NG12 for suspected cancer recognition and referral ¹.