CTR Abstracting & Coding 3

Question 1

When the primary site of a tumor cannot be determined after thorough workup, which ICD-O-3 topography code is assigned?

Accepted Answer

C80.9

Answer

C80.9 is assigned for unknown primary site when no primary site can be identified despite workup.

Question 2

Which of the following is the correct sequence for assigning the primary site when a biopsy is taken from a lymph node and the pathology shows metastatic squamous cell carcinoma of unknown primary?

Accepted Answer

Code C80.9 unknown primary

Answer

When the primary site cannot be established, C80.9 is used regardless of histology or lymph node location.

Question 3

What does the AJCC TNM suffix 'yp' indicate when documented on a pathology report?

Accepted Answer

The staging reflects post-neoadjuvant therapy pathologic findings

Answer

The 'yp' prefix in AJCC TNM staging denotes pathologic staging performed after neoadjuvant (pre-surgical) therapy.

Question 4

A registrar reviews a case where surgery removed a colon tumor and 18 lymph nodes were examined, with 3 positive. How should the regional lymph node fields be coded?

Accepted Answer

Number examined: 18, number positive: 3

Answer

Both the total nodes examined and the number of positive nodes are recorded separately to support accurate N-category staging.

Question 5

Which source document takes PRIORITY when there is a conflict between the operative report and the pathology report regarding tumor size?

Accepted Answer

Pathology report

Answer

The pathology report takes priority over the operative report for tumor size, as it provides the definitive microscopic measurement.

(CTR) Certified Tumor Registrar Practice Test

(CTR) Certified Tumor Registrar Practice Test

CTR Abstracting & Coding 3