Minimally invasive thoracoscopic resection of a micronodular thymoma with lymphoid stroma via a subxiphoid single-incision approach: A case report.

RATIONALE: This study aims to present a novel surgical approach for the resection of anterior mediastinal tumors, specifically focusing on micronodular thymoma with lymphoid stroma (MNT), a rare and distinct variant of thymoma. The single subxiphoid incision technique, although reported in limited cases, offers a minimally invasive option with potential benefits. We report the case of a 76-year-old male who underwent this innovative procedure and was diagnosed with MNT, providing insight into the management and outcomes of this rare pathology. PATIENT CONCERNS: The patient presented for the excision of an anterior mediastinal tumor, with the surgery facilitated by sternal hooks to improve visualization. The rarity of MNT and its unclear prognosis underscore the need for enhanced diagnostic accuracy and tailored treatment strategies. DIAGNOSES: Initially diagnosed preoperatively with a thymic cyst, the patient's final diagnosis was revised to MNT following surgery, highlighting the diagnostic challenges associated with this rare tumor. INTERVENTIONS: The tumor was successfully removed using minimally invasive thoracoscopic surgery through a subxiphoid single-incision, demonstrating the feasibility and potential advantages of this approach. OUTCOMES: The patient had a favorable postoperative course, with a swift recovery and no complications, and remained in good health without signs of relapse at the 9-month follow-up. LESSONS: This case underscores the importance of recognizing the unique pathological features of MNT and the need for a cautious diagnostic approach to differentiate it from other cystic lesions. Additionally, the successful use of single-port thoracoscopy under the xiphoid process for the removal of thymic tumors suggests its potential as an effective surgical method for these challenging cases.

Neuroendocrine neoplasms of the thymus.

Neuroendocrine neoplasms of the thymus (tNENs), including typical carcinoid, atypical carcinoid, large cell neuroendocrine carcinoma, and small cell carcinoma, are rare tumors with scarce clinical and pathological data available in the literature. They share many common features with neuroendocrine neoplasms in other organs, such as those in the lungs, while demonstrating some distinct clinical and pathological features. This review aims to give an updated overview of each category of tNENs, focusing primarily on the pathologic diagnosis and differential diagnosis of these tumors.

Multiple Postoperative Lung Infections after Thymoma Surgery Diagnosed as Nontuberculous Mycobacterial Infection.

BACKGROUND: Thymomas are thymic epithelial-derived, most common primary anterior mediastinal masses. Non-tuberculous mycobacteria (NTM) are species that do not cause leprosy and belong to species outside the Mycobacterium tuberculosis complex. METHODS: With the clinical application of targeted next-generation sequencing (tNGS), we promptly confirmed a case of NTM infection combined with NTM infection after thymoma surgery, and we performed a joint literature analysis of the two diseases to improve clinicians' understanding and recognition of lung infections after thymoma surgery. RESULTS: Chest CT of both lungs showed multiple hyperdense shadows. Sputum bacterial culture and characterization detected Neisseria Dryad and Streptococcus Grass Green. The presence of Mycobacterium abscessus infection was confirmed by alveolar lavage fluid sent for second-generation macro gene sequencing. CONCLUSIONS: The body's immune function decreases after thymoma surgery. When empirical anti-infection treatment for recurrent pneumonia in the lungs is ineffective, we should be alerted to the possibility of the presence of pulmonary non-tuberculous mycobacterial infection, and next-generation sequencing should be performed promptly to arrive quickly at a diagnosis.

[Thymoma in a young adult cat]. / Thymom bei einer jung-adulten Katze.

Thymomas and mediastinal lymphomas are the most common mediastinal neoplasms in cats. While mediastinal lymphoma occurs primarily in younger cats (approximately 2 to 4 years of age), thymomas are diagnosed almost exclusively in older cats. However, the following case shows that this is not necessarily always the case.A 3-year- and 11-month-old neutered male European Shorthair was presented with a preliminary report of exercise intolerance and restricted respiration. Both symptoms occurred primarily at high ambient temperatures. Radiographically, a mediastinal mass filled a significant part of the thoracic cavity. A computed tomographic examination and ultrasound-guided TruCut biopsy were performed. Histologic examination suggested a thymoma. A sternal thoracotomy and resection of the circumferential proliferation was conducted. Subsequent histopathologic examination confirmed the suspected diagnosis of a mediastinal thymoma. The cat recovered well postoperatively, and a clinical and radiographic follow-up examination was unremarkable after 8 months.

Spindle epithelial tumor with thymus-like elements (SETTLE): a diagnostic challenge with distinct therapeutic implication; case report.

Spindle epithelial tumor with thymus-like elements (SETTLE) is a rare malignant neoplasm of the thyroid gland which is believed to arise from intrathyroidal thymic tissue. It predominantly affects young adults and children presenting with a thyroid mass of variable duration and rarely occurs in adults. It has a high overall survival with a tendency for delayed metastasis. SETTLE is a biphasic lobulated tumor composed of spindle shaped cells along with glandular formations seen on histopathological examination. Despite its typical morphology it is commonly misdiagnosed on histopathology due to its rarity and overlapping morphology with other close mimics such as a carcinoma, synovial sarcoma and thymoma. Herein we report such a case occurring in a middle aged female presenting with a neck mass. She had an initial diagnosis of metastatic poorly differentiated squamous cell carcinoma possibly with an orophayngeal primary in view of co expression of CK, p40 and p16 on immunohistochemistry. The patient underwent surgical resection with modified neck dissection. On review at our hospital it was diagnosed as SETTLE and she remains disease free after a follow-up period of 1 year. Diligent histopathological examination espoused with a judicious panel of IHC markers in conjunction with clinicoradiological findings forms the mainstay of diagnosis. Diffuse and strong p16 immunoexpression has not been documented or evaluated in literature so far, and needs to be explored for its diagnostic utility in this rare entity.

Lymphocyte-Directed Immunomodulation Remits Thymoma-Associated Autoimmune Pneumonitis.

BACKGROUND: Thymoma presents with several autoimmune manifestations and is associated with secondary autoimmune regulator (AIRE) deficiency. Pneumonitis has recently been described as an autoimmune manifestation associated with thymoma presenting with similar clinical, radiographic, histological, and autoantibody features as seen in patients with inherited AIRE deficiency who suffer from Autoimmune PolyEndocrinopathy-Candidiasis-Ectodermal Dystrophy (APECED) syndrome. OBJECTIVES: To treat two patients with biopsy-proven thymoma-associated pneumonitis with lymphocyte-directed immunomodulation. METHODS: Two patients with thymoma were enrolled on IRB-approved protocols at the NIH Clinical Center. We performed history and physical examination; laboratory, radiographic, histologic and pulmonary function evaluations; and measurement of the lung-directed autoantibodies KCNRG and BPIFB1 prior to and at 1- and 6-months following initiation of lymphocyte-directed immunomodulation with azathioprine with or without rituximab. RESULTS: Combination T- and B-lymphocyte-directed immunomodulation resulted in improvement of clinical, functional, and radiographic parameters at 6-month follow-up evaluations in both patients with sustained remission up to 12-36 months following treatment initiation. CONCLUSION: Lymphocyte-directed immunomodulation remitted autoimmune pneumonitis in two patients with thymoma.

Thymic carcinosarcoma with melanocytic differentiation in a dog.

Carcinosarcomas are very rare tumors in dogs. Although carcinosarcomas with melanocytic differentiation arising from organs other than the thymus have been described in humans, this type of tumor has not been reported in dogs in any part of the body. We observed such a tumor in the cranial mediastinum of an 11-year-old spayed female dachshund. The dog was admitted to the clinic because of coughing, sporadic regurgitation, and dyspnea. Thoracic ultrasonography and computed tomography revealed a large mediastinal mass that was surgically removed via sternotomy. The tumor was of thymic origin and demonstrated 3 distinct components: an epithelial component positive for pancytokeratin (AE1/AE3) and high molecular weight cytokeratin (CK5/CK6) with some cystic spaces; a mesenchymal component positive for vimentin; and in association with the epithelial part, a minor melanocytic component positive for Melan A. Histologic metastasis of the epithelial and melanocytic components was present within a tracheobronchial lymph node. The dog died 105 d after surgery, after an episode of acute dyspnea. Key clinical message: To the authors' knowledge, this is the first report of thymic carcinosarcoma with melanocytic differentiation.

Carcinosarcome thymique avec différenciation mélanocytaire chez un chienLes carcinosarcomes sont des tumeurs très rares chez le chien. Bien que des carcinosarcomes avec différenciation mélanocytaire provenant d'organes autres que le thymus aient été décrits chez l'homme, ce type de tumeur n'a été rapporté chez le chien dans aucune partie du corps. Nous avons observé une telle tumeur dans le médiastin cránien d'une femelle teckel stérilisée de 11 ans. Le chien a été admis à la clinique en raison de toux, de régurgitations sporadiques et de dyspnée. L'échographie thoracique et la tomodensitométrie ont révélé une masse médiastinale importante qui a été retirée chirurgicalement par sternotomie. La tumeur était d'origine thymique et présentait 3 composantes distinctes : une composante épithéliale positive pour la pancytokératine (AE1/AE3) et la cytokératine de haut poids moléculaire (CK5/CK6) avec quelques espaces kystiques; un composant mésenchymateux positif à la vimentine; et en association avec la partie épithéliale, un composant mélanocytaire mineur positif pour Melan A. Des métastases histologiques des composants épithéliaux et mélanocytaires étaient présentes dans un ganglion lymphatique trachéobronchique. Le chien est décédé 105 jours après l'intervention chirurgicale, à la suite d'un épisode de dyspnée aiguë.Message clinique clé :À la connaissance des auteurs, il s'agit du premier cas de carcinosarcome thymique avec différenciation mélanocytaire.(Traduit par Dr Serge Messier).

Intrathyroidal thymic carcinoma.

A young woman in her early 30s presented with a right thyroid mass and progressive hoarseness due to a right vocal cord palsy. The preoperative fine-needle aspiration cytology was classified as Bethesda V and she underwent a total thyroidectomy and neck dissection. Intraoperatively, the thyroid mass was adherent to the oesophagus, trachea and encasing the right recurrent laryngeal nerve which was sacrificed. Final histopathology diagnosed a rare subtype of thyroid cancer known as intrathyroidal thymic carcinoma (ITC). She was then sent for adjuvant radiotherapy after a multidisciplinary tumour board discussion. This case report highlights the difficulty in preoperative diagnosis of ITC and the importance of immunohistochemical staining in clinching the diagnosis. In view of its rarity, there have been no published consensus on the treatment of ITC, hence we would like to share some learning points through a comprehensive literature review.

Primary glomus tumor of the thymus in a 66-year-old patient.

We report a unique case of a 66-year-old man who was incidentally identified to have a mass in the thymus region by computerized tomography scan. CT revealed a well-defined 1.6 × 1 × 0.9 cm thymus mass with moderate uniform enhancement. Thoracoscopic thymectomy was performed, and the pathological diagnosis was primary glomus tumor of the thymus. There were no atypia or malignant histological features, and no primary tumors in other sites. To our knowledge, this is the first case of primary thymic glomus tumor reported in the literature.

Ectopic cervical thymoma: a rare entity in the anterior neck.

Thymoma is a rare malignancy with usual location in the antero-superior mediastinum. Ectopic cervical thymoma (ECT) is an extremely rare tumor that originates from ectopic tissue, and is caused by the aberrant migration of the embryonic thymus. Our patient was a 56-year-old man who had a nodular lesion in the neck for several years. Computed tomography and Enhanced magnetic resonance imaging were performed. He underwent surgery, and a histological examination resulted in a diagnosis of type AB thymoma.

Ectopic pleural thymoma with T-cell lymphocytosis and bone metastasis: a case report.

BACKGROUND: The diagnostic complexities that arise in radiographic distinction between ectopic pleural thymoma and other thoracic neoplasms are substantial, with instances of co-occurring T-cell lymphocytosis and osseous metastasis being exceedingly rare. CASE PRESENTATION: A 51-year-old woman was admitted to our hospital with dyspnea and chest pain. Upon imaging examination, she was found to have diffuse and nodular pleural thickening on the left side, collapse of the left lung and a compression in the second thoracic vertebrae. All lesions showed significant 18F-FDG uptake on 18F-FDG PET/CT examination. Furthermore, she exhibited T-cell lymphocytosis in her peripheral blood, lymph nodes, and bone marrow. After ruling out malignant pleural mesothelioma (MPM), lung cancer with pleural metastasis, and T-cell lymphoma, the definitive diagnosis asserted was ectopic pleural thymoma with T-cell lymphocytosis and bone metastasis. CONCLUSION: Physicians need to expand their knowledge of the imaging features of ectopic pleural thymoma. Cases with T-cell lymphocytosis may exhibit increased aggressiveness and prone to bone metastasis.

A case of thymoma presenting as pyrexia of unknown origin.

ABSTRACT: Pyrexia of unknown origin can be caused due to numerous infective and noninfective causes. It poses a diagnostic dilemma to the clinicians and requires a myriad of investigations for the confirmation of diagnosis. Thymomas are rare mediastinal tumors that present as anterior mediastinal mass; however, thymomas presenting as pyrexia of unknown origin has rarely been reported in the literature. We report an interesting case of a middle-aged male who presented as pyrexia of unknown origin due to thymoma.

Thymic carcinoma presenting with overlap polyarthritis and myositis: A rare paraneoplastic syndrome in childhood.

Thymic tumors are very rare neoplasms in children and account for less than 1% of mediastinal tumors in pediatric patients. One-third of the pediatric patients present with symptoms related to the compression of the tumor mass on the surrounding anatomic structures, and paraneoplastic syndromes such as myasthenia gravis, pure red cell aplasia, acquired hypogammaglobulinemia, and connective tissue disorders, which rarely occur in children with thymic tumors. Herein, we report a case of thymic carcinoma mimicking the symptoms of a connective tissue disease with symmetrical polyarthritis accompanying myositis, fever, weight loss, and malaise in a 15-year-old male patient. To our knowledge, this is the first case pediatric thymic carcinoma accompany with severe polyarthritis and myopathy, thus we have reviewed the current literature regarding the cases of thymic malignancies coexisting with paraneoplastic syndromes in children.

Ectopic cervical thymoma in myasthenia gravis: a case report.

BACKGROUND: Ectopic cervical thymoma (ECT) is an extremely rare tumor, especially in association with myasthenia gravis (MG). CASE PRESENTATION: We report a case of myasthenia gravis with an ectopic thymoma in the neck, whose myasthenic symptoms significantly improved after complete removal of the mass. A 55-year-old woman with generalized myasthenia gravis (MG) experienced worsening neuromuscular weakness after abruptly discontinuing pyridostigmine. Testing revealed acetylcholine receptor-antibody (AChR-Ab) positivity and a cervical mass initially thought to be thyroid or parathyroid was identified as a thymoma, type A. Post-surgery and radiation therapy, her myasthenic symptoms improved significantly with less prednisone and pyridostigmine requirements over time and no need for additional immunotherapies. CONCLUSIONS: Diagnosing ECTs is challenging due to rarity, atypical locations, and inconclusive fine needle aspiration cytology (FNAC) results, often misinterpreted as thyroid or parathyroid lesions. As proper management of patients with MG, including thymectomy, offers favorable clinical outcomes such as significant improvement in myasthenic complaints and reduced immunosuppressive medication requirements, clinicians should be vigilant of the ectopic locations of thymomas to ensure timely diagnosis and intervention.

A basaloid carcinoma with multilocular thymic cyst mimicking a mediastinal teratoma.

This case report details a rare thymic basaloid carcinoma initially misinterpreted as a mediastinal teratoma, underscoring the diagnostic challenges posed by such tumors. A 71-year-old female presented with an asymptomatic anterior mediastinal tumor discovered incidentally during a routine health examination. Surgical intervention, followed by pathological and immunohistochemical analysis including CK-pan, p63, p40, and CD117 molecules, led to a definitive diagnosis of basaloid carcinoma of the thymus. This case highlights the critical importance of differential diagnosis in mediastinal lesions, especially those presenting with multilocular thymic cysts on chest CT. The subxiphoid video-assisted thoracoscopic surgery enabled complete tumor resection with minimal trauma and favorable postoperative outcomes. The patient opted against further radiotherapy or chemotherapy and she has survived for over eight months without recurrence. This case report contributes to the growing understanding of thymic basaloid carcinoma, a rare and potentially aggressive thymic carcinoma subtype. It emphasizes the necessity for precise surgical techniques and enhanced diagnostic acumen among cardiothoracic surgeons and oncologists.