Most Commonly Missed CPC Exam Concepts (And How to Avoid Losing Points!)

The AAPC Certified Professional Coder (CPC) exam is challenging but absolutely passable—especially when you understand where most students lose points. In this post, we’ll walk you through real concepts identified by the AAPC. We'll also review sample questions, strategies, and insider tips to help you pass the CPC exam with confidence.

 

📌 Key Topics Students Most Often Get Wrong on the CPC Exam

1. Skin Lesions & Closure Coding

🟢 What You Need to Know:

• Differentiate between benign and malignant lesions.
• Understand simple closures are included in lesion excision codes (both benign and malignant).
• Only intermediate and complex closures are billed separately.

✅ Example:

• A 1.5 cm basal cell carcinoma removed from the cheek with 2mm margins on each side.
• Correct code: 11642 (Malignant lesion excision, 1.1 to 2.0 cm, face)
• Do not add a code for simple closure—it’s included per CPT guidelines.

 
2. Fracture Care & Casting

🟢 What You Need to Know:

• Most initial casting/splinting is bundled into the procedure (closed reduction, etc.).
• Code based on type of fracture treatment: closed, open, with or without manipulation.

✅ Example:

• Closed reduction with manipulation of a displaced midshaft humerus fracture.
• Correct code: 24505-LT
• Do NOT bill for the cast (29065)—it's included.

 

3. Medicare Preventive GYN Services

🟢 What You Need to Know:

• Medicare patients often require G-codes (not standard CPT).
• For pelvic and clinical breast exams: use G0101
• Pap smear collection: use Q0091

✅ Example:

• 68-year-old Medicare patient gets routine pelvic & clinical breast exam.
• Correct code: G0101

 

4. Selective Catheterization (Cardiology)

🟢 What You Need to Know:

• Code only the highest order vessel accessed.
• Use Appendix L for vascular family hierarchy.

✅ Example:

• Catheter placed into the left renal cortical artery branch (3rd order).
• Correct code: 36247

 

5. OB Global Package for Twin Deliveries

🟢 What You Need to Know:

• You do not double-bill prenatal/postnatal care for twins.
• Use the global code for 1st delivery + an additional vaginal delivery code for the 2nd baby.

✅ Example:

• Vaginal delivery of twins after previous C-section.
• Correct codes: 59610 (global) + 59612-51 (2nd vaginal delivery)

 

6. Chemodenervation Coding (e.g., Botox)

🟢 What You Need to Know:

• Code by extremity and by number of muscles treated per extremity.
• 90460 (first component) + 90461 (each additional component)

✅ Example:

• Arms: 2 injections (1–4 muscles) each → 64642, 64643
• Legs: 6 injections (5+ muscles) each → 64644, 64645

 

7. Screening Mammogram (Preventive)

🟢 What You Need to Know:

• Identify screening vs diagnostic.
• Choose bilateral if no 50 modifier is indicated.

✅ Example:

• Routine bilateral screening mammogram with CAD.
• Correct code: 77067

 
8. Hormone Suppression Testing

🟢 What You Need to Know:

• Use the panel code if all components are included in documentation.

✅ Example:

• Growth hormone suppression test with multiple blood draws.
• Correct code: 80430

 

9. Vaccine Administration (Component-Based)

🟢 What You Need to Know:

• Pediatric vaccine coding is per component if counseling is documented.
• Use 90460 (first component) + 90461 (each additional).

✅ Example:

• DTAP-IPV-HepB (Pentacel) + Pneumococcal vaccine.
• DTAP has 5 components; Pneumococcal has 1.
• Correct codes: 90460 ×2 (first of each) + 90461 ×4 (additional components)

 

10. E/M Coding – Time-Based With Prolonged Services

🟢 What You Need to Know:

• 99215 for visits ≥40 minutes (established patient).
• 99417 for each 15 minutes of prolonged time (beyond base time).

✅ Example:

• 55 minutes total → 15 min over 99215
• Correct codes: 99215, 99417

 

11. Medicare Vaccine Administration (G-Codes)

🟢 What You Need to Know:

• Use G0009 for pneumococcal vaccine administration in Medicare patients.
• Avoid CPT codes like 90471 in this context.

✅ Example:

• Medicare patient receives pneumococcal vaccine.
• Correct code: G0009

 

🧠 Final Tips for CPC Exam Success:

• Know your guidelines cold—especially what’s included vs separately reported.
• Flag tough questions and come back later.
• Practice navigating both CPT and HCPCS manuals quickly.
• Memorize key modifiers and Appendix L vascular trees.
• Train with a legit course—like Preppy or AAPC—avoid shady “real exam questions” online.