Cancer Screening Recommendations for Membranous Nephropathy with PLA2R and THSD7A Positivity

Risk Assessment

Dual positivity for PLA2R and THSD7A on kidney biopsy is exceedingly uncommon and signals a markedly higher risk of associated malignancy than PLA2R positivity alone; the presence of PLA2R antibodies does not rule out cancer‑associated disease. 1
THSD7A‑positive membranous nephropathy is linked to a greater prevalence of concurrent malignancies compared with PLA2R‑positive disease, warranting heightened suspicion for cancer. 1

All patients with membranous nephropathy should receive age‑appropriate cancer screening (e.g., colonoscopy, mammography, prostate‑specific antigen testing, and chest imaging) as a baseline evaluation. 2
When THSD7A positivity is identified, screening should extend beyond standard age‑based measures to include more intensive investigations, such as urological assessment (cystoscopy and renal imaging) and gastrointestinal endoscopy, reflecting the known associations with bladder and colon cancers. 1
A contrast‑enhanced CT scan of the chest, abdomen, and pelvis is recommended to detect occult solid tumors in patients with THSD7A‑positive membranous nephropathy. 2

Serial measurement of both anti‑PLA2R and anti‑THSD7A antibody titers is advised to identify serologic shifts that may precede clinical changes or signal emerging malignancy. 1

Do not assume that a positive PLA2R antibody excludes secondary etiologies; evaluation for malignancy, autoimmune diseases, infectious causes, and drug‑induced nephropathy should be performed regardless of antibody status. 1
Relying solely on routine age‑appropriate cancer screening is insufficient when THSD7A is present; enhanced surveillance protocols are required. 1