The whole point of the lumps pathway is to separate the rare soft-tissue sarcoma from the very common benign lump, because the cost of missing it — or of excising it unplanned — is high. NICE NG12 (updated April 2026) keys its adult recommendation on one feature: an unexplained lump that is increasing in size earns an urgent direct-access ultrasound, and a suggestive or uncertain scan with persisting concern earns a suspected cancer pathway referral. Children and young people get the same logic on a 48-hour clock. The size, depth and pain criteria come from the UK sarcoma specialists' guideline (Hayes et al, 2024) rather than from NG12, and they are best used as extra reasons to image and to lower your threshold, not as a checklist that must be complete. The cardinal error is calling such a lump a lipoma and shelling it out, which contaminates tissue planes and compromises the definitive operation. A tumour may be smaller than 5 cm and still be malignant, so do not wait for a threshold. Lumps in the breast, axilla, neck and testis have their own NG12 routes, an unexplained thyroid lump has its own NG12 thyroid cancer route, and persistent, enlarging or otherwise suspicious nodes follow the lymphoma recommendations in clinical context.

History triages the lump along a single axis: how it is behaving over time. A soft, mobile lump that has been unchanged for years is almost always benign, whereas any lump that is new, growing, or has recurred after a previous "lipoma" excision earns imaging — growth is also the exact trigger NG12 uses. Pain is a useful but asymmetric clue: its presence is a red flag, but its absence is not reassuring. Systemic symptoms point towards lymphoma or metastasis, and a relevant background (neurofibromatosis type 1, prior radiotherapy to the field) raises the pre-test probability of malignancy. In a population study from north-west England, the lifetime risk of malignant peripheral nerve sheath tumour in NF1 was estimated at 8–13% (Evans et al, J Med Genet 2002), which is why a neurofibroma that changes behaviour deserves urgent attention.

A structured examination of the lump — site, size, shape, surface and consistency, plus depth — captures the features that drive the decision. Benign lumps tend to be superficial, soft or fluctuant, mobile and well-defined: a lipoma slips under the examining finger and a cyst may have a punctum — but slip sign and transillumination are not reliable enough to exclude sarcoma or confirm a cyst. The features that move a lump onto the imaging pathway are growth, size over 5 cm, a deep (sub-fascial) position, fixation and a hard irregular consistency. Asking the patient to tense the underlying muscle is a quick bedside test of depth. Documenting size in centimetres creates the baseline against which growth — the NG12 trigger — is judged at review. Always examine the regional nodes: a node draining the lump changes the differential.

The differential is dominated by a few benign diagnoses — lipoma, epidermoid cyst, ganglion and reactive lymph node — each with a recognisable bedside signature. Holding the malignant possibilities alongside them (sarcoma, lymphoma, metastasis, skin cancer) is what keeps the pathway safe, because a deep, growing "lipoma" is exactly how a sarcoma presents. Two NG12 skin recommendations matter here: consider a suspected cancer pathway referral for a skin lesion that raises the suspicion of squamous cell carcinoma, and for a pigmented or non-pigmented lesion that suggests nodular melanoma. Trauma-related lumps (haematoma, fat necrosis) and infective ones should declare themselves on history and resolve with time; persistence or atypical behaviour still prompts imaging.

Imaging, not surgery, is the first investigation for any lump that is not clearly a simple benign lesion. Ultrasound is the accessible first-line test that distinguishes cystic from solid, gauges size and depth, and flags lesions that need the sarcoma service — and NG12 gives GPs direct access to it for exactly this purpose. The UK sarcoma guideline (Hayes et al, 2024) advises that a tissue diagnosis should, where possible, be made before treatment by percutaneous core biopsy reviewed by a specialist sarcoma pathologist. An unplanned local procedure contaminates the tissue planes the definitive operation must clear, so biopsy and excision of a possible sarcoma belong to the specialist team. A clear request (size, depth, growth, "?sarcoma") helps the radiologist triage and apply the right protocol.

Referral follows the red-flag assessment directly. The headline route is the NG12 soft-tissue sarcoma pathway — triggered by a growing unexplained lump, usually after an urgent ultrasound — with parallel routes for bone sarcoma (X-ray first), for unexplained lymphadenopathy (lymphoma), and for lumps in organ-specific sites (breast, axilla, neck, thyroid, testis, skin). In England, suspected cancer pathway referrals are now measured against the Faster Diagnosis Standard (cancer diagnosed or ruled out within 28 days), which NG12 reflected in its October 2023 change of terminology. Everything that is confidently benign and merely symptomatic goes via routine routes, and many areas restrict removal of benign lipomas and ganglia to set criteria. The skill is matching the lump to the correct pathway rather than defaulting to local excision.

For the genuinely benign lumps, management is mostly reassurance with selective removal for symptoms, function or diagnostic doubt — a confirmed small lipoma or a quiet cyst needs nothing more than safety-netting. The NHS England and Academy of Medical Royal Colleges Evidence-Based Interventions programme restricts routine removal of benign skin lesions and wrist ganglia to defined criteria, so explaining the natural history (many ganglia settle) avoids frustration later. Two rules keep this safe: every excised lump goes for histology, and no lump with sarcoma features is excised locally. Abscesses are drained, with antibiotics reserved for surrounding cellulitis or systemic involvement; recurrent abscesses deserve assessment for hidradenitis suppurativa, diabetes, chronic staphylococcal carriage (including PVL-producing staphylococci) or immunodeficiency.

Because the great majority of lumps are benign, the most valuable intervention is clear, specific reassurance paired with equally specific safety-netting. Patients remember concrete triggers — rapid growth, new pain, size beyond a golf ball, fixation or skin change — far better than a vague instruction to return if worried, and dated photographs against a ruler turn "I think it's bigger" into evidence. After any excision, closing the loop on histology is part of safe care, and patients with predisposing conditions such as neurofibromatosis type 1 need to know which changes in a known lump should prompt urgent review.

Safety-netting is what makes a "benign lump" diagnosis safe over time, because the single most important sarcoma sign — growth — only declares itself later. Documenting size in centimetres creates the baseline, and a planned re-measure converts uncertainty into a decision. The patient should leave knowing the specific changes that mandate re-imaging and referral. Two system-level nets matter just as much: ensuring every excised lump's histology is reviewed and acted on, and treating recurrence at an excision site as suspicious regardless of the first label. In the SCA, examiners reward a clear explanation of why a scan is needed despite a probably benign lump, an honest mention that the aim is to rule out something serious, and a concrete follow-up plan.