Biopsy and its indications

Pleural biopsy

The procedure is indicated for patients in whom clinical presentation and imaging methods are insufficient to determine the causes of pleural thickening or effusion. Histological confirmation is required.

• Blind closed biopsy: Performed using Abrams needles (Abrams biopsy). Rarely used in modern practice, except in regions with a high incidence of tuberculosis.
• Percutaneous cutting needle biopsy: Performed under mandatory image guidance (image-guided cutting needle biopsy).
• Medical thoracoscopy: Considered the method of choice when malignant effusion is suspected, as both diagnosis and therapeutic drainage can be performed in a single intervention. Percutaneous access is reserved for patients unable to tolerate thoracoscopy.

Important: When mesothelioma is suspected, the number of punctures is kept to a minimum. There is a high risk of tumor cell seeding along the needle tract (tumor seeding).

The choice of imaging modality depends on the lesion location. Ultrasound provides real-time guidance and involves no radiation exposure, whereas CT is indispensable for accessing areas hidden behind the ribs or located along paravertebral surfaces.

Bone biopsy

A minimally invasive procedure with a low complication rate, completely replacing open surgical bone biopsy. It is performed using cutting or trephine needles. The introduction of rechargeable power drills has facilitated access to hard osteosclerotic lesions and reduced procedure-related pain.

Main indications:

1. Identification of primary tumors or bone infections (e.g., aspiration from the intervertebral disc in spondylodiscitis).
2. Staging of malignant disease.
3. Histological comparison in synchronous or metachronous cancer.
4. Suspected metastasis (performed exclusively if the result will directly influence treatment management).

During the preparation stage, correlating the planned biopsy with MRI and radiography data is critical to avoid traumatizing typical benign lesions (the "do not touch" rule — do not touch lesions). Interventions on the spine, sacrum, and iliac bones are usually performed with the patient in the prone or lateral position, under fluoroscopic guidance (using bone landmarks) or CT guidance (for soft tissue visualization).

Biopsy preparation and hemostasis management

The decision regarding skeletal interventions is made by a multidisciplinary team including an oncologist, radiologist, neurosurgeon, and cytopathologist. The procedure is performed under conscious sedation (conscious sedation) or general anesthesia.

Special attention is paid to the blood coagulation system:

• The only absolute contraindication to spinal biopsy is hemorrhagic diathesis. Massive blood loss or epidural hematoma formation with subsequent spinal cord compression may occur.
• Platelet count must be maintained above 50,000/µL (otherwise transfusion is indicated).
• The INR must not exceed 1.3–1.5 (fresh frozen plasma or cryoprecipitate is transfused for higher values).
• Antiplatelet agents are discontinued at least 5 days prior to spinal puncture.

Renal biopsy

The primary indication is the need for histological confirmation of diagnosis in nephrotic syndrome, glomerular diseases, and IgA nephropathy.

The standard technique is percutaneous puncture under ultrasound guidance. If the risks of percutaneous access outweigh the benefits (presence of contraindications), open surgical intervention is used. Complications are rare and include subcapsular hematoma and arteriovenous fistula formation.

Class and exam questions

What else to study on this topic

• Complications of image-guided pleural interventions
• Pleural cavity drainage: indications and the "safe triangle"
• Imaging methods for the urinary tract (antegrade and retrograde pyelography)
• Congenital renal anomalies: agenesis, ectopia, and horseshoe kidney

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.