Tumoral Calcinosis

• Rare disease: overall incidence estimated at roughly 1 in 100,000 to 1 in 1,000,000
• Familial (primary hyperphosphataemic): autosomal recessive, presents in 1st-2nd decade, often in children of consanguineous parents; described in clusters from the Middle East, North Africa and Turkey
• Secondary (uraemic): the clinically dominant form, rising in prevalence with the dialysis population
• Endemic reports: high-frequency clusters described in parts of sub-Saharan Africa and Papua New Guinea, often associated with low calcium, high phosphate dietary patterns
• Sex: familial form shows no strong sex predilection; secondary form tracks with CKD demographics

• Diagnostic confusion with bone or soft-tissue tumour - biopsy or excision is the typical referral pathway
• Mechanical symptoms - large masses restrict joint motion, irritate bursa, compress nerves
• Skin breakdown - ulceration with chalky 'toothpaste' discharge (pathognomonic when present)
• Functional limitation - sitting, walking, dressing all impaired
• Recurrence after incomplete excision - the single most common reason for repeated referrals

• Mass duration: years of slow, often painless growth is the rule
• Pain: usually late, when mass irritates bursa, compresses nerve or ulcerates skin
• Discharge: chalky white 'toothpaste' through skin is pathognomonic
• Renal disease: dialysis vintage, transplant status, medications (calcium-based binders, vitamin D analogues)
• Family history: sibling or parental cases (autosomal recessive)
• Diet and drugs: high phosphate intake, vitamin D supplementation, calcium supplements

• Mass: firm, lobulated, 'stony-hard', non-tender, often warm but not inflamed
• Mobility: usually fixed to deep soft tissues, not to skin (until late)
• Skin: tethering, erythema, ulceration, sinus tracts
• Joint: range often preserved unless mass mechanically blocks it
• Neurovascular: document function pre-op (sciatic at hip, axillary at shoulder, ulnar at elbow)
• Lymph nodes: not enlarged (reassuring against malignancy)

• Tumoral calcinosis is rare worldwide - incidence estimated at roughly 1 in 100,000 to 1 in 1,000,000
• Familial hyperphosphataemic form clusters in populations with high consanguinity - Middle East, North Africa, Turkey, parts of South Asia
• Secondary (uraemic) form is rising globally as the dialysis population grows - the most common clinical scenario in high-income settings
• Endemic clusters of tumoral calcinosis-like lesions have been described in sub-Saharan Africa and Papua New Guinea, often associated with low calcium, high phosphate dietary patterns
• Site distribution is consistent across regions: hip, shoulder, elbow, wrist, hand

• High-resource: tertiary orthopaedic oncology and metabolic bone units offer genetic testing, FGF23 assays, modern phosphate binders, calcimimetics, and access to renal transplantation
• Limited-resource: dietary phosphate restriction, low-cost aluminium-based or calcium-magnesium binders, and acetazolamide remain the backbone of therapy; genetic testing rarely available
• Dialysis adequacy is the strongest single modifiable factor in the uraemic form - more frequent or longer sessions are protective
• Surgical excision is widely available but recurrence remains high without metabolic correction
• No global arthroplasty or implant registry is relevant - tumoral calcinosis is a soft-tissue metabolic disease

Familial hyperphosphataemic tumoral calcinosis almost always recurs after surgery, but a young patient with a large, ulcerating, infected mass cannot be left untreated. The threshold for surgery is therefore a clinical decision weighing symptoms, anatomy, recurrence risk, and the patient's wishes. There is no randomised evidence to guide this.

Burosumab is licensed for X-linked hypophosphataemia and tumour-induced osteomalacia, where it lowers phosphate by neutralising excess FGF23. In familial hyperphosphataemic tumoral calcinosis, FGF23 is elevated but dysfunctional - the response to burosumab is biologically plausible but unproven. Case reports suggest benefit, but there are no randomised trials, and cost and access are major barriers.

KDIGO suggests normalising phosphate in CKD-MBD, but in dialysis patients with established tumoral calcinosis the target is debated. Aggressive phosphate lowering may reduce new lesions but risks overshooting into hypophosphataemia, hungry bone, and adynamic bone disease. Individualised targets are accepted in practice but poorly evidence-based.

Complete primary excision is associated with lower recurrence than debulking, but in deep anatomical sites (sciatic notch, subdeltoid) complete excision carries real risk of nerve injury. There is no comparative trial. The pragmatic approach is: complete excision where safe, debulking where complete is unsafe, and aggressive metabolic control regardless.

Genetic testing is clearly useful in children, sibling cases, and consanguineous families. Its value in isolated adult cases, especially in uraemic patients, is less clear. Finding a heterozygous GALNT3 or FGF23 variant may not change management but does affect family counselling.

'Cure' means different things: anatomical (mass gone), biochemical (phosphate normal), genetic (mutation absent - impossible in familial), and patient-centred (symptom-free, functional). Most familial patients achieve only biochemical and patient-centred control, not anatomical cure.