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Official Description

Phosphatase, acid; prostatic

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 84066 refers to the laboratory test for measuring prostatic acid phosphatase (PAP) levels in the blood. Prostatic acid phosphatase is an enzyme that is primarily produced by the prostate gland and is found in high concentrations in seminal fluid. This enzyme plays a role in the fusion of endosomes, which is essential for creating an acidic environment necessary for various biological processes. Elevated levels of PAP can indicate several medical conditions, including benign prostatic hyperplasia (BPH), prostate cancer, infections, or infarction of the prostate. Additionally, conditions such as Paget's disease and Gaucher's disease may also lead to increased PAP levels. It is important to note that prostate manipulation procedures, such as biopsy or massage, can temporarily elevate PAP levels for a duration of 24 to 48 hours post-procedure. While the PAP test is not recommended for routine screening purposes, it can be valuable in predicting disease recurrence and monitoring the effectiveness of treatment in patients already diagnosed with prostate-related conditions. The test is performed by obtaining a blood sample through a venipuncture, and the serum is analyzed using a quantitative chemiluminescent immunoassay method, which provides precise measurements of PAP levels in the bloodstream.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The prostatic acid phosphatase (PAP) test, represented by CPT® Code 84066, is indicated for the following conditions:

  • Benign Prostatic Hyperplasia (BPH) - Elevated PAP levels may be observed in patients suffering from this non-cancerous enlargement of the prostate gland.
  • Prostate Cancer - The test can help in monitoring patients diagnosed with prostate cancer, as increased levels of PAP may indicate disease progression or recurrence.
  • Prostate Infection - Infections affecting the prostate can lead to elevated PAP levels, making this test useful in the diagnostic process.
  • Prostate Infarction - Conditions that result in reduced blood flow to the prostate may also elevate PAP levels.
  • Paget's Disease - This bone disorder can cause increased levels of prostatic acid phosphatase.
  • Gaucher's Disease - Similar to Paget's disease, Gaucher's disease may also result in elevated PAP levels.

2. Procedure

The procedure for obtaining the prostatic acid phosphatase (PAP) test involves several key steps:

  • Step 1: Patient Preparation - Prior to the test, the patient may be advised to avoid certain activities that could affect PAP levels, such as prostate manipulation (biopsy or massage) for a specified period.
  • Step 2: Venipuncture - A qualified healthcare professional performs a venipuncture to collect a blood sample from the patient. This step is crucial as the quality of the sample can impact the accuracy of the test results.
  • Step 3: Serum Separation - After collection, the blood sample is processed to separate the serum, which contains the prostatic acid phosphatase enzyme. This step is essential for accurate measurement.
  • Step 4: Testing Method - The serum is then analyzed using a quantitative chemiluminescent immunoassay. This advanced testing method allows for precise quantification of PAP levels in the serum.

3. Post-Procedure

After the PAP test is completed, the patient may be advised to resume normal activities. However, it is important to monitor for any potential side effects from the venipuncture, such as bruising or discomfort at the site of blood draw. The results of the PAP test will be interpreted by the healthcare provider, who will consider the levels in conjunction with the patient's clinical history and other diagnostic findings. Follow-up appointments may be necessary to discuss the results and any further actions required based on the findings.

Short Descr ASSAY PROSTATE PHOSPHATASE
Medium Descr ASSAY OF PHOSPHATASE ACID PROSTATIC
Long Descr Phosphatase, acid; prostatic
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 1
CCS Clinical Classification 233 - Laboratory - Chemistry and Hematology
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
GA Waiver of liability statement issued as required by payer policy, individual case
77 Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
91 Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient.
GY Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit
Date
Action
Notes
2013-01-01 Changed Medium Descriptor changed.
Pre-1990 Added Code added.
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