Growing thymic granuloma adjacent to a thymic cyst mimicking malignancy: a case report
Tetsu TakedaTakashi EguchiSachie KoikeTsutomu KoyamaShunichiro MatsuokaKentaro MiuraKazutoshi HamanakaYayoi SatohTakeshi UeharaKimihiro Shimizu
2
Citation
11
Reference
10
Related Paper
Citation Trend
Abstract:
An association between thymic cyst and thymic epithelial malignancy has been previously reported. However, several case studies have reported granulomas in the thymus with high metabolic activity, mimicking thymic malignancy. Additionally, an inflammatory response provoked by the rupture of cyst walls has been proposed as a pathogenesis of cholesterol granuloma in the thymus. However, the natural growth history of thymic granuloma remains unclear. We herein report the first case demonstrating the natural growth history of a thymic granuloma adjacent to a thymic cyst. Ten-year follow-up of the thymic cyst revealed a growing nodular lesion with high metabolic activity adjacent to the cyst. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) showed a maximum standardized uptake value of 12.1 in a 2.5-cm solid mass. We performed total thymectomy given a high suspicion of a malignant thymic epithelial tumor. Histopathologic examination revealed a cholesterol granuloma in the thymus, which was directly connected to the thickened region of the cystic wall through a rupture of the wall. This case highlights the importance of considering thymic granuloma as a differential diagnosis for a growing anterior mediastinal nodule with high metabolic activity. Further, the clinical course and histopathologic findings of this case provide supporting evidence for the proposed pathogenesis of thymic granuloma.Keywords:
Thymectomy
Nodule (geology)
Pathogenesis
Thymectomy has been performed in 69 patients, 58 females and 11 males, age range 14 to 70 years, with a maximum in females between 20 to 30 years. Twenty-seven percent of the patients were older than 40 years. Considerable improvement resulting from remission and partial remission occurred in 89% of females and in about 50% of males, the figure for thymomatous myasthenia was about 65% in the first year after thymectomy. In the following years, improvements increased partially and the number of remissions rose as well. By chance the duration of the disease was longer than 6 years in 20% of our patients and in these a benefit from thymectomy was also found. There were 7 early deaths and 4 late deaths. Thymectomy cannot be called a cure but is an essential part of the whole treatment procedure of myasthenia comprising the administration of anticholinesterase and especially immunosuppressive agents. It was found difficult to estimate the effect of any single measure in this retrospective study by the major benefit of thymectomy is seen in initiating remissions or at least considerable improvements. Indication for operation is thought to be present in progressive myasthenia, acute or chronic, and thymoma, provided that the patient has reached an optimal condition preoperatively by adequate anticholinesterase adjustment, neurophysiological control and immunosuppressive treatment. Thymectomy is not an emergency operation and should be carefully planned. Since relapses after thymectomy are not rare, a careful neurological long-term follow-up appears obligatory.
Thymectomy
Cite
Citations (4)
Abstract In recent years much progress has been made in the investigation of the pathophysiology, characterizing subgroups, and extension of multimodal treatment of myasthenia gravis (MG). This applies especially to the role of thymectomy (Thx). Thymectomy is always indicated for thymoma-associated myasthenia gravis. Furthermore, based on large cohort studies, during recent decades thymectomy has also become a central part of immune-modulating MG therapy in patients without thymoma. The lack of randomized studies, however, caused a certain persistent reluctance as to the significance of thymectomy. The current MGTX trial has shown the effectiveness of thymectomy. A significant improvement of myasthenic complaints and the reduction of immunosuppressive medication was primarily shown for acquired early-onset MG (EOMG) with complete resection of all thymic tissue. Because the MGTX study only included patients younger than 65 years with generalized MG and positive for acetylcholine-receptor antibodies, at present the significance of Thx for other relevant subgroups as juvenile MG, MG in older patients, ocular MG, as well as seronegative patients is under investigation. Even the prevailing opinion of no benefit of thymectomy for MuSk-positive patients probably needs reevaluation based on ambiguous findings. With respect to surgery, based on the exclusive performance of extended median sternotomy for MG in the MGTX, the value of thoracoscopic modifications for thymectomy as a minimally-invasive alternative is currently under evaluation. For clinical reasons further judgment regarding different minimally-invasive thymectomy techniques compared to the conventional open procedures in the form of randomized comparative studies would be required. Currently, however, an experience-based robotic-assisted thoracoscopic unilateral approach to thymectomy meets all requirements related to surgical, clinical-neurological and patient aspects. Ethical reasons, therefore, will lead to other strategies for comparison of different surgical techniques.
Thymectomy
Cite
Citations (4)
It is well known that the nodular involvement of the muscle occurs in patients with a background disease such as sarcoidosis, tuberculosis, lepra and so on. Such nodules are histologically evaluated as non-caseating epithelioid granulomas. We experienced a curious case that had a nodule which was a non-caseating epithelioid granuloma, but without any background disease.It was a sixty-year-old female. She had suffered from a painful nodule for 2 months on the left lower leg. We first suspected a malignant tumor of soft tissue because of the findings in several examinations, but histological examination of the biopsied specimen resulted in noncaseating epithelioid granuloma. The excision was done and two other nodules appeared after 3 months at the right calf and the left thigh, respectively. Those were the same in histological examination as the previous nodule. No background disease could not be found during approximately 2 years of the observation period in spite of our careful examination. We, therefore, diagnosed as muscular sarcoid. It would seem to be a very rare case.
Nodule (geology)
Histopathological examination
Cite
Citations (0)
Myasthenia gravis (MG) is an autoimmune disease that affects the neuromuscular junction causing fluctuating weakness of skeletal muscles. It is considered a rare disease with an estimated prevalence of 7.77/100,000. Surgical treatment is done by simple or extended thymectomy. Although thymectomy has been used in the treatment of MG since 1941, the role of thymectomy for MG is not completely understood. Perhaps, one of the longest unresolved issues in thoracic surgery is the role of thymectomy in the treatment of MG. Persistent questions and issues involve not only the surgical approach to thymectomy, but also the role of thymectomy itself in the treatment of MG. This article focuses on the review of thymectomy in MG patients.
Thymectomy
Cite
Citations (0)
Myasthenia gravis (MG) is a rare condition caused by autoantibodies against acetylcholine receptors on postsynaptic membrane that leads to weakness of skeletal muscles. About 7 of 10 patients with MG have thymic hyperplasia and about 1 of 10 patients have thymoma. Thymectomy has increasingly been used as a treatment modality for MG. Several observational studies have shown that thymectomy results in improvement in MG and a randomized trial has established that thymectomy leads to a better outcome in non-thymomatous generalized MG. However, thymectomy is yet controversial in some disease subtypes and there are potential concerns regarding the selection of the ideal surgical approach to achieve complete removal of the thymic tissue to achieve stable remission rates. This review highlights the role of thymectomy in non-thymomatous and thymomatous MG, the effectiveness of various thymectomy methods, postoperative myasthenic crisis, and remission after thymectomy.
Thymectomy
Cite
Citations (14)
The formation of pulmonary nodules is associated with benign or malignant pathologies. Based on the sizes, growth rates, and morphological features of nodules, surgical treatment or follow-up can be performed. Pulmonary nodules are frequently encountered in the practice of thoracic surgery. A 37-year-old male patient who had a 2.0¥1.9 cm nodule in the right lung was followed. His medical history revealed no chronic disease. During follow-up, the sizes of the nodule increased and, therefore, it was removed by wedge resection. The pathological examination result was reported as a larval granuloma. In conclusion, larval granulomas in the lung are extremely rare phenomena and should be further examined.
Nodule (geology)
Wedge resection
Solitary pulmonary nodule
Cite
Citations (0)
Objective To improve the diagnosis and differential diagnosis of mediastinal cysts.Methods 36 patients with mediastinal cyst proved by surgery and pathology were collected, and CT findings were analyzed retrospectively.Results In all 36 cases,CT defined the masses with clear margin, thin wall and fluid-like density content which had no enhancement after intravenous contrast administration. There were neurenteric cyst(n=1), bronchial cyst(n=12), esophageal cyst(n=2), pericardial cyst(n=5), dermoid cyst(n=7), lymphangioma(n=4), thymic cyst(n=4) and non-special cyst(n=1). Conclusion The diagnosis of mediastinal cyst and differential diagnosis from other cystic lesions can be made according to the characteristics on plain and post-contrast CT scans.
Lymphangioma
Dermoid cyst
Cite
Citations (0)
Thymectomy
Cite
Citations (22)
The benefits of thymectomy in non-thymomatous patients with myasthenia gravis (MG) remain controversial. The first detailed case of thymectomy in a patient with MG was reported in 1939, following which many cases were published. In 2000, Gronseth and Barohn reported the first meta-analysis of the effectiveness of thymectomy in MG patients without thymoma. They reviewed 28 papers systematically and reached these conclusions: (1) The benefit of thymectomy in non-thymomatous autoimmune MG has not been conclusively established, and (2) a well-designed controlled trial is essential. Following this report, Newsom-Davis et al. designed a thymectomy trial for non-thymomatous MG patients receiving prednisone (the MGTX study). Their study compared extended trans-sternal thymectomy (ETTX) combined with prednisone and prednisone alone groups with the aim to answer 3 questions: (1) Is the former more effective in improving myasthenic weakness? (2) Does the former require a lower total dose of prednisone, and thus decrease the likelihood of concurrent and long-term toxic effects? (3) Does the former enhance patients' quality of life by reducing adverse events and symptoms associated with the therapy? Currently, 67 centers, including our institute, are involved in this study. In total, 106 patients have been enrolled (the recruitment goal is 150). The patients are scheduled for a 5-year follow-up. The MGTX study will offer new information on the role of thymectomy in improving the quality of life of patients with MG.
Thymectomy
Cite
Citations (2)
Thymectomy
Ocular myasthenia
Cite
Citations (0)