Usefulness of Endoscopic Tattooing Before Neoadjuvant Therapy in Patients with Clinical Complete Response in Locally Advanced Rectal Cancer for Providing a Safe Distal Surgical Margin.

Background: Endoscopic tattooing of colorectal tumors enables tumor localization and determination of appropriate surgical margins. It becomes very difficult to detect the distal surgical margins (DSMs) of rectal tumors in patients who obtain clinical complete response (cCR) after neoadjuvant therapy. In this study, our aim is to examine the benefits of endoscopic tattooing of the tumor before neoadjuvant therapy in patients with locally advanced rectal cancer in accurate localization of the previous tumor and in providing appropriate DSMs in cases with cCR. Patients and Methods: The patients who were diagnosed with locally advanced rectal cancer, received neoadjuvant therapy and subsequently achieved cCR, and underwent surgery between January 2015 and October 2020 were included in the study. The patients were divided into two groups according to whether they were endoscopically tattooed before neoadjuvant chemoradiotherapy. Results: A total of 49 cases were included in the study. Significantly better DSMs were observed especially in female gender in the tattooed group. DSMs were found to be closer to the resection margins in the nontattooed group. It was found that endoscopic tattooing had a significant effect on the DSM in the regression analysis (P = .06, R2 = 0.47). It was determined that laparoscopy or open surgery alone did not differ in terms of DSMs but open surgery together with tattooing was found to be strongly effective in providing larger DSMs. Conclusion: In locally advanced rectal cancer, endoscopic tattooing of the distal margin of the tumor before neoadjuvant therapy is a reliable and effective method for obtaining a safe DSM and not leaving the residual tumor at the lower end of anastomosis, especially in cases of cCR.

Diagnostic value of lymph node fine-needle aspiration cytology.

OBJECTIVES: This study aims to assess the diagnostic accuracy of cytology by comparing the results of fine-needle aspiration cytology (FNAC) and histopathologic examination. MATERIAL AND METHODS: A 4-year retrospective study design was conducted on FNAC samples from the lymph nodes of patients in our hospital between January 2015 and December 2018. The cytopathological diagnoses were compared with the histopathological results of the same excised lymph nodes. Diagnostic sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy rate were calculated. RESULTS: A total of 392 lymph nodes were aspirated during the study period. Cytologic analysis of the lymph nodes revealed the following: Reactive lymphoid hyperplasia, 239 (61%); metastatic, 61 (15.6%); granulomatous lymphadenitis, 24 (6.1%); suspicious, 24 (6.1%); pyogenic abscess, 10 (2.6%); necrosis, 4 (1%); non-Hodgkin lymphoma, 2 (0.5%); and non-diagnostic, 28 (7.1%). Immunohistochemical analysis was performed on 26 (6.6%) cases to the cell block samples. Histopathological correlation was available in 73 (18.7%) cases. The overall diagnostic sensitivity, specificity, PPV, and NPV of FNAC of lymph nodes were 87.9%, 100%, 100%, and 89.7%, respectively. The overall diagnostic accuracy was 94.1%. In case of malignancies, the histopathological correlation was 100%. Of four cases with false negative, three were low-grade non-Hodgkin lymphoma and one was granulocytic sarcoma. CONCLUSION: FNAC of lymph nodes is a safe, easy, cheap, quick diagnostic tool and reduces the need for diagnostic excisional biopsy in many patients. Cytological diagnosis can be supported with immunohistochemical analysis of cell block samples. However, lymphomas, particularly low-grade non-Hodgkin lymphomas, are a diagnostic challenge and additional studies such as flow cytometry are required in cases with suspicious for lymphoma.