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Official Description

Biopsy, soft tissue of back or flank; superficial

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

Biopsy of soft tissue of the back or flank involves the removal of a small sample of tissue from the superficial layers of the skin and underlying structures. This procedure is essential for diagnosing various conditions, including infections, tumors, or other abnormalities. The term "soft tissue" encompasses a variety of structures, including muscles, tendons, fat, blood vessels, lymph vessels, nerves, and the tissues surrounding joints. The biopsy is typically performed under local, regional, or general anesthesia, or with conscious sedation, depending on the specific site and depth of the biopsy. Prior to the procedure, the area over the biopsy site is thoroughly cleansed to minimize the risk of infection. A careful incision is made to access the tissue, ensuring that surrounding blood vessels and nerves are protected during the dissection. Once the tissue sample is obtained, it is sent to a laboratory for histological evaluation, which is reported separately. After the sample is collected, the incision is closed with sutures to promote proper healing. For superficial biopsies, the appropriate code to use is 21920, while deeper tissue biopsies that require more extensive dissection should be coded as 21925.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

Biopsy of soft tissue of the back or flank is indicated for various clinical scenarios, including:

  • Suspicion of Tumors The procedure is performed when there is a suspicion of benign or malignant tumors in the soft tissue of the back or flank.
  • Infection It may be indicated in cases where there is a suspected infection in the soft tissue that requires histological confirmation.
  • Inflammatory Conditions The biopsy can be used to evaluate inflammatory conditions affecting the soft tissues, helping to determine the underlying cause.
  • Unexplained Masses When a patient presents with an unexplained mass or lesion in the back or flank area, a biopsy is often necessary to obtain a definitive diagnosis.

2. Procedure

The procedure for a superficial soft tissue biopsy of the back or flank involves several key steps:

  • Preparation The patient is positioned comfortably, and the area over the planned biopsy site is cleansed with an antiseptic solution to reduce the risk of infection.
  • Anesthesia Administration Depending on the depth and location of the biopsy, local, regional, or general anesthesia, or conscious sedation, is administered to ensure the patient’s comfort during the procedure.
  • Incision A careful incision is made in the skin over the biopsy site. The surgeon dissects through the soft tissue layers to reach the mass or lesion while taking care to avoid damaging any nearby blood vessels and nerves.
  • Tissue Sample Collection Once the mass or lesion is accessed, a tissue sample is obtained. This sample is critical for histological evaluation and diagnosis.
  • Closure After the tissue sample is collected, the incision is closed using sutures to promote healing and minimize scarring.

3. Post-Procedure

After the biopsy procedure, the patient is monitored for any immediate complications. Instructions for post-procedure care typically include keeping the biopsy site clean and dry, monitoring for signs of infection such as increased redness, swelling, or discharge, and managing any discomfort with prescribed pain relief. The patient may be advised to avoid strenuous activities for a specified period to allow for proper healing. Follow-up appointments may be scheduled to discuss the results of the histological evaluation and any further management based on the findings.

Short Descr BIOPSY SOFT TISSUE OF BACK
Medium Descr BIOPSY SOFT TISSUE BACK/FLANK SUPERFICIAL
Long Descr Biopsy, soft tissue of back or flank; superficial
Status Code Active Code
Global Days 010 - Minor Procedure
PC/TC Indicator (26, TC) 0 - Physician Service Code
Multiple Procedures (51) 2 - Standard payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 1 - Statutory payment restriction for assistants at surgery applies to this procedure...
Co-Surgeons (62) 0 - Co-surgeons not permitted for this procedure.
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Hospital Part B services paid through a comprehensive APC
ASC Payment Indicator Office-based surgical procedure added to ASC list in CY 2008 or later with MPFS nonfacility PE RVUs; payment based on MPFS nonfacility PE RVUs.
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) P6B - Minor procedures - musculoskeletal
MUE 2
CCS Clinical Classification 159 - Other diagnostic procedures on musculoskeletal system
51 Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d).
58 Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78.
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
78 Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.)
79 Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.)
CC Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed)
GC This service has been performed in part by a resident under the direction of a teaching physician
GW Service not related to the hospice patient's terminal condition
LT Left side (used to identify procedures performed on the left side of the body)
X5 Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
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