Reasoning GP · Algorithm · 1-page summary
Abdominal or pelvic mass
For: a new or unexplained palpable abdominal or pelvic mass, found by the patient or on examination. Children: block 1 only (very urgent specialist route). Not for: acute abdominal pain without a mass (use the abdominal pain algorithm) or jaundice alone (jaundice).
Core rule: exclude a ruptured AAA, obstruction and an acute abdomen first. Then treat any unexplained mass as cancer until FIT, imaging and the right NICE NG12 route say otherwise — never reassure without investigation.
0Stop — call 999 now — before any further examination
- Pulsatile central or epigastric mass, or known AAA, with sudden severe abdominal, back or flank pain, collapse or haemodynamic compromise → 999. Do not palpate vigorously.
- Obstruction (vomiting, distension, failure to pass stool or wind), peritonism or perforation, ovarian torsion (sudden severe unilateral pelvic pain, vomiting, peritonism) → 999 emergency surgical admission. Painful or irreducible hernia → A&E
- Child with an abdominal mass who is acutely unwell; LUQ mass after trauma with haemodynamic compromise → 999
- While waiting: two large-bore IV accesses; resuscitate per the local major-haemorrhage protocol; contact vascular surgery via the emergency pathway; nil by mouth. No laxatives. Do not delay transfer for imaging.
1Triage — who is in front of you
| Patient | Action |
|---|---|
| Child | Palpable mass or unexplained enlarged organ → ≤48 h specialist; Same-day if unwell. Do not examine repeatedly. |
| Fever + tender mass | RUQ + travel → Same-day hepatology / ID. RIF (appendix mass) → Same-day surgical |
| Stable adult | FIT, bloods, NG12 route by site (block 2) |
2Screen — NICE NG12 route by site — any adult
- Abdominal mass → FIT; ≥10 µg Hb/g → Suspected cancer colorectal. Negative or missing FIT never delays referral if concerned. Rectal mass → refer, no FIT.
- Woman: pelvic or abdominal mass or ascites, not obviously fibroids → Suspected cancer gynaecology; do not wait for CA125 or USS.
- Upper abdominal mass: like an enlarged liver or gallbladder → consider Urgent direct-access USS; like stomach cancer → consider Suspected cancer upper GI.
- Jaundice, 40+ → Suspected cancer pancreatic. 60+, weight loss + diarrhoea, back or abdominal pain, nausea, vomiting, constipation or new diabetes → consider Urgent direct-access CT (USS if no CT).
- Splenomegaly or nodes, unexplained → consider suspected cancer referral. Left supraclavicular node → Suspected cancer for the likely primary.
3Assess — once blocks 0–1 are answered
☐ Observations, weight trend, LMP ☐ Mass: site, size, consistency, mobility, pulsatility (expansile = aneurysm); ascites; hernias; left supraclavicular node; PR if it alters management ☐ FBC, U&E, LFTs, CRP; HbA1c if pancreatic; urinalysis; pregnancy test; FIT. Not here: tumour-marker panels (CEA, CA19-9) or blanket CT; CA125 only per the ovarian pathway.
4Classify — by region, then block 2
- RUQ / epigastric — liver, gallbladder (Courvoisier suggests, never proves, cancer), stomach, pancreas, aorta.
- LUQ — spleen (cannot get above it, notched) vs left kidney (ballotable). Unsure → USS.
- RIF / LIF — caecal or sigmoid cancer, appendix or diverticular mass, Crohn's, ovary.
- Suprapubic — bladder (catheterise), pregnant uterus (urine hCG), fibroids, ovary → USS.
- Faecal mass — cannot exclude cancer clinically: image if any doubt; treat only once obstruction excluded; persists → urgent referral.
- Uncertain — say so; follow block 2 for the likely site. Never "watch" it.
5Treat today — only these
- Pain: paracetamol; strong opioid only via the local acute-pain or palliative pathway (immediate-release, reviewed).
- Nausea: metoclopramide (max 5 days; not in obstruction, perforation, GI bleed) or ondansetron (QT). Doses: NICE/SPC, BNF, local formulary.
- No high-dose or bulk-forming laxatives if obstruction is possible.
- Tell them: suspected cancer pathway = prompt tests, not a diagnosis. Written plan; Macmillan; fit note if needed.
6Refer routinely
- Premenopausal simple ovarian cyst <5 cm: no routine follow-up; 5–7 cm: consider yearly USS; >7 cm, persistent, enlarging, symptomatic or complex → gynaecology.
- Postmenopausal cyst symptomatic, complex, persistent or enlarging → gynaecology. Benign lesion → specialist if symptomatic.
- After an appendix mass: confirm the surgical team has arranged follow-up to exclude caecal cancer.
7Never reassure by
- A normal FIT, CA125 or ultrasound while symptoms persist or progress.
- A "constipation mass" that softens with laxatives.
- Back or flank pain labelled renal colic or muscular in an older man with a possible AAA.
- A midline mass after surgery assumed to be adhesions.
- A referral sent but never tracked.
8Safety-net — verbal and written, then document it
999 “Call 999 if you collapse, get sudden severe tummy or back pain, the lump grows quickly or pulsates, you vomit with a swollen tummy and cannot pass stool or wind, or you vomit blood or bleed heavily from the back passage. Painful or stuck hernia: A&E now.” Same day “Contact us or NHS 111 today for worsening pain, persistent vomiting or not keeping fluids down, black stools or other rectal bleeding, fever with shivers, yellow skin, confusion or feeling rapidly worse.”
Tracking: log the referral date; no contact in 14 days → chase; act on a rejection, delay or DNA. Acutely unwell → A&E, do not wait.
✓Safe to leave primary care only if — all five, documented
No block 0 or same-day row applies
Mass characterised; pregnancy and retention excluded
FIT, bloods and NG12 route by site requested
Referral date logged and tracking set
Verbal and written safety-net given
Summary of the full Reasoning GP abdominal mass algorithm, which holds the examination signs, mass types, ovarian cyst detail and evidence. Sources: NICE NG12 (updated April 2026), NG151, CG122; RCOG Green-top Guidelines 62 and 34; MHRA Drug Safety Updates; local suspected cancer pathways. Clinical reference — follow local pathways and check doses: NICE/SPC, BNF.