KCD (Carfilzomib/Cyclophosphamide/Dexamethasone) Regimen for the Treatment of Newly Diagnosed POEMS Syndrome

Inclusion Criteria:

1. Newly diagnosed POEMS syndrome meeting the Dispenzieri diagnostic criteria (2023 version);
2. Age 18-75 years;
3. ECOG performance status 0-3, with an estimated life expectancy >3 months;
4. No active infective diseases;
5. No prior anti-POEMS therapy except for corticosteroids;
6. No severe organic impairment of major organs, meeting the following laboratory requirements: creatinine clearance ≥40 mL/min, total bilirubin ≤1.5 × upper limit of normal (ULN); AST and ALT ≤2.5 × ULN; cardiac enzymes <2 × ULN; left ventricular ejection fraction within normal range on echocardiography, and no clinically significant electrocardiogram abnormalities;
7. Absolute neutrophil count ≥1.5 × 10^9/L without prior growth factor support; platelet count ≥50 × 10^9/L without platelet transfusion within 7 days prior to screening; hemoglobin ≥60 g/L;
8. Ability to swallow and take medication orally;
9. Completion of all screening and assessments as outlined in the study protocol;
10. Signed informed consent for chemotherapy.

Exclusion Criteria:

1. POEMS syndrome complicated by multiple myeloma, light chain amyloidosis, or Waldenström macroglobulinemia;
2. HIV positivity, or active hepatitis A, hepatitis B, or hepatitis C infection; or hepatitis B virus DNA >10^2 copies/mL;
3. Concurrent severe unstable medical conditions, including heart failure, renal failure, liver failure, bleeding disorders, arterial/venous thrombotic events within 6 months, uncontrolled diabetes mellitus, or a history of active hemorrhagic cystitis;
4. History of autoimmune diseases (e.g., Crohn's disease, rheumatoid arthritis, systemic lupus erythematosus) within the past 2 years that caused end-organ damage or required systemic immunosuppressive or disease-modifying therapy;
5. Severe active infections (e.g., untreated tuberculosis, pulmonary aspergillosis);
6. Presence of other malignancies (except non-melanoma skin cancer, in situ cervical, bladder, or breast cancer with disease-free survival >5 years);
7. Epilepsy requiring medication, dementia, or other mental status abnormalities that interfere with understanding or complying with the study protocol;
8. Drug use, medical, psychological, or social conditions that may interfere with study participation or outcome assessment;
9. Pregnancy or breastfeeding;
10. Any condition deemed by the investigator to make the patient unsuitable for enrollment.