Case Series
AB049. Continuing challenges of primary neuroendocrine neoplasms of the thymus: clinicopathological characteristics of an uncommon tumor in a case series
Rahma Ayadi1,2,3, Rahma Yaiche1,2,3, Yasmine Dhouibi1, Emna Braham1,2, Olfa Ismail1,2, Nadia Ben Jamaa1,3, Aida Ayadi1,2,3
1Pathology Department, Abderrahmen Mami Hospital, Ariana, Tunisia;
2Research Laboratory, Ariana, Tunisia;
3Faculty of Medicine of Tunis, El Manar University, Tunis, Tunisia
Correspondence to: Rahma Ayadi, MD. Pathology Department, Abderrahmen Mami Hospital, Rue de l’Hôpital, 2080 Ariana, Tunisia; Research Laboratory, Ariana,Tunisia; Faculty of Medicine of Tunis, El Manar University, Tunis, Tunisia. Email: rahma.ayadi@fmt.utm.tn.
Background: Primary neuroendocrine neoplasms (PNEs) of the thymus are highly aggressive tumors that rarely occur. They account for 2–5% of all thymic neoplasms, and only 0.4% of all PNEs. Relatively few previously published studies have focused on neuro-endocrine tumors (TNEs). The aim of this study was to describe clinicopathological characteristics of this aggressive entity with literature review.
Case Description: We report a retrospective study of 8 cases of PNEs of the thymus, diagnosed at our department of pathology and treated at our institution, with a hindsight of 20 years, from 2004 to 2024. The review of these 8 cases showed that there was no sex preponderance, with 4 male and 4 female patients, aged between 32 and 64 years, with a mean age of 49 years. The diagnosis was made on surgical resection (n=5) and transparietal biopsy (n=3). Intraoperative frozen sections were performed (n=7), showing a malignant tumor process (n=4), a non-small cell carcinoma (n=2) and malignancy that may be consistent with non-Hodgkin’s lymphoma or thymic carcinoma (n=1). The histological examination revealed tumors of only two subtypes and grades: intermediate grade carcinoid tumors (n=6) and high grade neuroendocrine carcinomas (n=2). The tumor cells shared similar immunohistochemical patterns, as all of the 8 cases were positive for synaptophysin and chromogranin, negative for muscle actin, PS100, CD5 and thyroid transcription factor-1 (TTF1). However, they are positive for CD56 (n=6), epithelial membrane antigen (EMA) (n=3) and pancytokeratin (n=1).
Conclusions: Primary NEs of the thymus were observed to be an extremely aggressive but very rare malignant lesion. Their main differential diagnoses are extension or metastases of their bronchopulmonary counterparts. Early diagnosis and surgical resection are the most important methods to improve prognosis. In the future, multi-center, large-sample database and clinical studies are urgently needed to explore better treatment modality.
Keywords: Neuroendocrine neoplasms (PNEs); thymus; case series
Acknowledgments
None.
Funding: None.
Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://med.amegroups.com/article/view/10.21037/med-25-ab049/coif). The authors have no conflicts of interest to declare.
Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.
Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.
doi: 10.21037/med-25-ab049
Cite this abstract as: Ayadi R, Yaiche R, Dhouibi Y, Braham E, Ismail O, Jamaa NB, Ayadi A. AB049. Continuing challenges of primary neuroendocrine neoplasms of the thymus: clinicopathological characteristics of an uncommon tumor in a case series. Mediastinum 2025;9:AB049.
