ABSTRACT
Background: Low-grade appendiceal mucinous neoplasms (LAMN) of the appendix have bland cytological features and well-differentiated morphology. Despite this, they may cause a pseudomyxoma peritonei (PMP) disease characterized by mucinous deposits in the peritoneal cavity and may exhibit malignant behavior. Aims and Objectives: In this study, we evaluated the clinical course and histopathological findings of LAMN. The rate of progression to PMP, factors affecting its development, and the clinical course of cases with PMP were investigated. Materials and Methods: Twelve thousand and forty-seven cases who underwent appendectomy were reviewed, and 71 mucinous lesions cases whose slides are in our archive were included in the study. Histopathological findings were re-evaluated. Morphological findings that guide the differential diagnosis, the clinical course of the patients, and factors affecting PMP development were determined. Results: The cases were divided into group 1 non-neoplastic (9.9%), group 2 benign (18.3%), group 3 LAMN (60.6), and group 4 malignant neoplasms (11.3%). Age, gender, appendix diameter, gross appearance, epithelial characteristics, and presence of microcalcification were significantly different between the patient groups. The presence of mucin in the ileocecal region was found to be significant in the development of PMP. It was observed that the additional procedure performed after the appendectomy did not prevent a recurrence. Conclusion: LAMNs are lesions with characteristic findings and different behaviors. The only method to distinguish from the lesions included in the differential diagnosis is to interpret the histopathological findings correctly. Additional operations after appendectomy do not contribute to preventing recurrence.
ABSTRACT
Background: Papillary thyroid microcarcinoma (PTM) is a relatively common entity in the general population. PTM is often asymptomatic and is detected incidentally during the histopathological examination of thyroidectomy specimens from operations because of benign thyroid disease. Aims: The aims of the study are to determine the incidence of incidental papillary thyroid microcarcinomas (IPTMs) in our center, to examine the clinicopathologic characteristics of these tumors, and to present our experiences. Materials and Methods: This study includes 827 patients who underwent thyroidectomy operation in our center between January 2013 and June 2017 and were examined histopathologically in the Pathology Clinic. Patients' demographic characteristics, preoperative diagnoses, operative procedure, histopathological findings, and postoperative prognostic indexes are presented. Results and Conclusion: Of the 827 patients, 138 (16.6%) were diagnosed with a malignancy. Of these, 124 were papillary carcinoma, 5 were follicular carcinoma, 4 were lymphoma, 2 were medullary carcinoma, 2 were anaplastic carcinoma, and 1 was poorly differentiated carcinoma. The IPTM incidence rate was 8.01%; the multifocality and bilaterality rates were 23.3% and 13.3%, respectively. In 98.3% of IPTM cases, total thyroidectomies were performed, and in 1.7% of cases, subtotal thyroidectomy was performed followed by complementary thyroidectomy. No relapse or metastasis was detected in any of these cases. A careful histopathological examination of the thyroidectomy specimen is essential because IPTM is frequently skipped in fine needle aspiration cytology. We consider it best to perform total thyroidectomies because bilaterality and multifocality rates are high in IPTM. Long-term life expectancy in these tumors is quite good.