Microscopic Precision: The Application Landscape Of Soft Tissue Biopsy Needles Across Clinical Fields

The term "soft tissue" encompasses all tissues in the human body excluding hard tissues such as bone, teeth, and nails. This includes muscle, fat, fibrous tissue, blood vessels, nerves, and various glands and organs. Consequently, the application scope of soft tissue biopsy needles is exceptionally broad, spanning nearly all clinical departments.

1. Oncology: The Cornerstone of Diagnosis and Molecular Subtyping

This is the most critical application area for biopsy needles. Whether addressing breast cancer, lung cancer, liver cancer, prostate cancer, or lymphoma, obtaining histopathological evidence remains the gold standard for definitive diagnosis.

• Breast Nodules:​ Core Needle Biopsy (CNB) has replaced open surgical biopsy as the standard protocol. Under ultrasound guidance, 14G or 16G biopsy needles acquire sufficient tissue to differentiate between benign and malignant lesions, determine hormone receptor status (ER/PR), and assess HER2 expression levels-providing the foundation for subsequent targeted therapies.
• Pulmonary Masses:​ Percutaneous Transthoracic Needle Biopsy (PTNB) typically utilizes 18G–20G aspiration or cutting needles. Due to the aerated nature of lung tissue and respiratory motion, high requirements are placed on the firing speed of the needle and the stability of the coaxial system. The primary complication is pneumothorax, occurring at a rate of approximately 5%–30%, closely correlated with needle gauge and the number of passes.
• Liver Occupying Lesions:​ Given the liver's rich vascularity and high bleeding risk, 17G–18G automatic firing needles combined with coaxial cannula techniques are commonly employed for rapid acquisition under ultrasound or CT guidance. Obtained tissues are used to differentiate primary hepatocellular carcinoma from metastatic tumors and to conduct viral hepatitis DNA testing.
• Prostate Cancer:​ Transrectal or transperineal biopsy remains the gold standard. Traditionally, systematic 12–14 core sampling is performed using 18G Tru-Cut needles. Recently, with the advancement of MRI fusion technology, targeted biopsy needles have emerged. These enable precise sampling of suspicious regions with high PI-RADS scores identified on MRI, significantly improving the detection rate of clinically significant prostate cancer.

2. Rheumatology and Musculoskeletal System: Unveiling Inflammatory and Degenerative Diseases

Many rheumatic and muscular disorders require biopsy for definitive diagnosis and severity assessment.

• Inflammatory Myopathies:​ Conditions such as polymyositis and dermatomyositis typically utilize 14G–16G semi-automatic biopsy needles to acquire tissue from specific muscles (e.g., quadriceps, deltoid) under ultrasound guidance. Pathological examination revealing myofiber degeneration, necrosis, regeneration, and inflammatory cell infiltration serves as the diagnostic gold standard.
• Rheumatoid Arthritis:​ Synovial biopsy is becoming increasingly vital. Via arthroscopy or ultrasound-guided fine-needle aspiration, hyperplastic synovial tissue is obtained to analyze inflammatory cytokine expression, assess disease activity, and even guide the selection of biologic agents.
• Soft Tissue Sarcomas:​ For deep-seated masses in the extremities or trunk, biopsy is the preferred diagnostic method. Strict adherence to the principle of "puncturing along the long axis while avoiding major neurovascular bundles" is required to prevent tumor seeding. 14G–16G coaxial cannula biopsy needles are typically utilized.

3. Infectious Diseases: Probes for Locking Down Pathogens

For unexplained fevers, abscesses, or granulomatous lesions, biopsy needles access the center of the lesion to obtain specimens for microbial culture, PCR testing, and histopathological examination.

• Spinal Infections:​ Diagnosing discitis or vertebral osteomyelitis often requires CT-guided percutaneous biopsy. An 11G–13G bone biopsy needle is used to traverse bone, followed by an 18G–20G soft tissue needle to acquire pus or granulation tissue.
• Deep Fungal Infections:​ Such as pulmonary aspergilloma or hepatosplenic candidiasis. Biopsy not only identifies hyphae but also facilitates susceptibility testing to guide antifungal therapy.

4. Transplantation and Regenerative Medicine: Windows for Assessing Organ Status

• Post-Renal Transplantation:​ Routine protocol biopsies of the transplanted kidney are the gold standard for monitoring acute rejection, drug nephrotoxicity, and the progression of chronic kidney disease. Typically, 16G–18G automatic firing needles are used under ultrasound guidance to obtain tissue cores containing at least 10 glomeruli.
• Stem Cell Therapy:​ In clinical trials, biopsy needles are utilized to extract mesenchymal stem cells from bone marrow or adipose tissue. Alternatively, they are used post-treatment to acquire tissue from target organs (e.g., heart, liver) to evaluate cell homing, survival, and differentiation.

From molecular subtyping of tumors to pathological confirmation of rare diseases, from tracing the source of infections to monitoring graft function, the soft tissue biopsy needle has transcended its role as a mere diagnostic tool. It has become an indispensable bridge connecting basic research with clinical decision-making, driving the era of personalized medicine.