What are the recommended referral criteria for a patient suspected of having a paraneoplastic syndrome in primary care?

There are no specific, separate referral criteria explicitly stated for paraneoplastic syndromes in the provided UK primary care guidelines. However, patients suspected of having paraneoplastic syndromes should be assessed for underlying malignancy based on associated symptoms and signs that suggest cancer.

Recommended approach in primary care includes:

• Assess for symptoms and signs that may indicate an underlying cancer, such as unexplained weight loss, fatigue, fever, night sweats, lymphadenopathy, or other systemic features.
• If clinical features suggest a possible cancer, consider urgent investigation or a suspected cancer pathway referral according to the relevant symptom-based criteria (e.g., unexplained weight loss, persistent fatigue, unexplained fever, or lymphadenopathy) NICE NG12.
• Perform appropriate initial investigations in primary care, such as full blood count, chest X-ray, or tumour markers, guided by the clinical presentation NICE NG12.
• Refer urgently via the suspected cancer pathway if there is a high suspicion of malignancy based on clinical assessment and initial investigations NICE NG12.

In summary, the referral criteria for suspected paraneoplastic syndrome rely on identifying features suggestive of an underlying cancer and following the established urgent referral pathways for suspected cancer in primary care NICE NG12.