Primary objective: To evaluate the concordance of intraoperative frozen section in diagnosing tumors.
1. To compare the frozen section and the permanent section diagnoses of tissues submitted to the laboratory.
2. To assess concordance, discordance and deferred diagnoses between frozen section and permanent section diagnoses.
3. To determine reasons for discordance.
4. To identify anatomic sites associated with discordant frozen sections.
BACKGROUND: Frozen section is a very helpful ancillary procedure to the surgeon in guiding him in his decision intraoperatively. Legitimate indications include: (1) to establish the presence and nature of lesion; (2) to determine adequacy of surgical margins; and (3) to establish whether the tissue obtained contained diagnosable material whether additional sampling is indicated. Based on several studies, the concordance of frozen section varies depending on the type of tissues. In this retrospective study (1994-2005), we reviewed and evaluated frozen section diagnc in 109 lesions. The most common site for frozen section diagnosis was the mediastinum, followed by the lung an breast. There is a high concordance of frozen section in diagnosing mediastinal, pulmonary and breast lesions Because it is very difficult to diagnose lymphoma sometimes due to its resemblance to normal lymphoid tissues a frozen section, there was 1 case of false negative diagnosis. This is also true in diagnosing breast tumor wherein a single case of frozen section of a breast tissue had a deferred diagnosis. Frozen section has some limitations like friable tissues, hemorrhagic sample, freezing artifacts and small sample. Sometimes, these pitfalls are unavoidable and are causes of discordance. Furthermore, we recommend good communication between the surgeon and pathologist to avoid misdiagnosis. (Author)