15. Guidelines for Intratumoral Injection of Chlorine Dioxide in Prostate Cancer

15.1 Indications

• 15.1.1 Can be the primary treatment option for prostate cancer.

• 15.1.2 Suitable for patients who cannot or do not wish to undergo surgery.

• 15.1.3 Applicable for recurrence after surgery or chemo/radiotherapy.

15.2 Contraindications

• 15.2.1 Cachexia, active diabetes or tuberculosis, and heart, lung, liver, or kidney failure.

• 15.2.2 Platelet count < 60×10⁹/L.

• 15.2.3 KPS score ≤ 50.

15.3 Puncture Needle and Auxiliary Instruments

• Use a 23G×15.0 cm or 25G×9.0 cm puncture needle, 10–20 ml high-pressure syringe, ultrasound, or CT machine.

15.4 Pre-treatment Preparation

• 15.4.1 Perform necessary examinations:

  • Routine blood, urine, and stool tests.

  • Liver and kidney function tests.

  • Tumor markers: CEA, PSA.

• 15.4.2 Discuss the procedure with the patient and sign a consent form.

• 15.4.3 Administer butorphanol 0.1g, antihemorrhagic agent 1KU, ondansetron 4-8mg, and optionally diazepam 5-10mg, 15 minutes before treatment.

15.5 Treatment Procedure

• 15.5.1 Under ultrasound or CT guidance, identify the puncture point in the lower abdomen, measure the distance to the tumor center, and confirm needle direction.

• 15.5.2 Disinfect the puncture site skin, wear sterile gloves, and use a sterile drape.

• 15.5.3 Administer local anesthesia with 2% lidocaine, stabilize the skin, insert the needle into the tumor center, then remove the needle core and inject chlorine dioxide solution. For tumors ≤4 cm, use a single-point injection with a dose of 30% of the tumor volume (ml); for tumors >4 cm, use multi-point injections based on tumor segment (cm).

• 15.5.4 Guide the procedure with ultrasound or CT, observing drug distribution within the tumor, and stop when saturation is achieved. Remove the needle.

• 15.5.5 Cover the site with sterile gauze and secure with tape.

• 15.5.6 Observe the patient for 5–10 minutes before returning them to the ward.

15.6 Post-treatment Care

• 15.6.1 Within the first week, monitor for fever, local pain, signs of peritonitis or pelvic inflammation, hematuria, and urinary irritation, and provide symptomatic treatment as needed. If infection is suspected, administer antibiotics and check blood and urine. After one week, reassess blood, urine, and liver and kidney functions, noting symptom relief.

• 15.6.2 For multiple treatments, allow a 7-day interval. Post-treatment observations remain the same as after the first session. At the end of the treatment cycle, assess peripheral blood T lymphocyte subsets (CD4, CD8) and perform ultrasound or CT to monitor immune status and tumor changes.