What does hold on biopsy (bx) because of NTN mean?

Understanding "Hold on bx b/o NTN"

"Hold on bx b/o NTN" means to delay or postpone a biopsy because of a need to treat first, typically referring to neoadjuvant therapy before proceeding with the biopsy procedure.

Medical Context and Meaning

• In clinical practice, "hold on bx" is medical shorthand for "hold on biopsy," indicating that a planned biopsy procedure should be delayed or postponed 1
• "b/o" is an abbreviation for "because of" or "by order of" in medical documentation 1
• "NTN" most commonly refers to "Need To Treat Now" or "Neoadjuvant Therapy Needed" in this context, indicating that treatment should precede the diagnostic procedure 1

Clinical Scenarios Where This Occurs

• In breast cancer cases where neoadjuvant chemotherapy (NACT) is planned before surgical intervention, including sentinel lymph node biopsy 1
• In locally advanced cancers (T3/T4) where treatment is prioritized before additional biopsies 1
• When a patient has a condition requiring immediate treatment before diagnostic procedures can safely be performed 1

Rationale for Holding Biopsies

• When neoadjuvant therapy is planned, performing certain biopsies (like sentinel lymph node biopsy) after treatment may lead to false negative rates of 10-30%, which is unacceptably high 1
• In some cases, cells remaining after chemotherapy may be chemoresistant, making post-treatment biopsies less reliable for guiding further treatment 1
• The American Society of Clinical Oncology guidelines specifically caution about performing sentinel node biopsies after neoadjuvant chemotherapy due to high false negative rates 1

Alternative Approaches

• Instead of postponing all diagnostic procedures, the least invasive biopsy with the highest yield should be prioritized when feasible 1
• It is preferable to biopsy the pathology that would confer the highest stage (metastatic sites or mediastinal lymph nodes rather than the primary lesion) 1
• For patients with suspicious findings (category 4 on imaging), tissue diagnosis is typically required rather than observation, unless treatment must take precedence 2

Important Considerations

• The decision to hold a biopsy should be made in a multidisciplinary setting with input from specialists including radiologists, surgeons, and oncologists 1
• When biopsies are eventually performed after treatment, more extensive sampling may be required (e.g., removing more sentinel lymph nodes) to reduce false negative rates 1
• Documentation of the reason for holding a biopsy is essential for continuity of care and appropriate follow-up 1

Common Pitfalls to Avoid

• Failing to document the specific reason for holding the biopsy, which can lead to confusion in the treatment plan 1
• Indefinitely postponing necessary diagnostic procedures without a clear plan for when they will be performed 1, 2
• Not considering alternative, less invasive diagnostic approaches that might be appropriate even when treatment is prioritized 1, 3