Histologic types of thymoma associated with pure red cell aplasia: a study of five cases including a composite tumor of organoid thymoma associated with an unusual lipofibroadenoma

Thymic lipofibroadenoma: A case report

Lipofibroadenoma (LFA) is an epithelial tumor. It has been seen rarely in the thymus, and only a handful of cases have been reported. LFA is usually seen in the anterior mediastinum and is defined as a coalescence of epithelial thymic, adipose, and fibrotic tissue. We present a 30-year-old female who presented due to an unrelated traffic accident. An incidental mass was found in her left anterior superior mediastinum. After performing a complete excision, a histologic examination of the excised mass revealed it to be LFA of the thymus, which is extremely rare. The follow-up period was uneventful. LFA is a slow-growing benign tumor and is very similar to fibroadenoma of the breast. The etiology and clinical findings are yet to be well-defined. It was only seen in men in the prior cases. But recent cases, including this one, have also reported female patients. The tumor is mainly observed in the anterior mediastinum, which was also the case in our patient. The gold standard of diagnosis is pathologic examination. Our examination showed strands and nests of thymic parenchyma, including Hassall corpuscles, which separated fibro adipose tissue. Thymectomy is the treatment of choice. It can be performed by either video-assisted thoracic surgery or open surgery. We performed open surgery. The most important prognostic factor for this tumor is staging.

Thymic epithelial tumours: histopathological classification and differential diagnosis

The epithelial and lymphoid compartments of the thymus can give rise to a wide variety of tumours, including thymomas, thymic carcinomas, lymphoreticular proliferations, germ cell tumours, and sarcomas. While some of these have close similarity to their counterparts in other organs, both in terms of histology and immunohistochemistry, as well as molecular features, others are unique to the thymus. The epithelial tumours, which can develop in the thymus, will be discussed in this review, with a particular emphasis on resolving differential diagnosis by means of morphology, immunohistochemical profiles, and molecular diagnostics.

Thymic lipofibroadenomas: Three case reports

BACKGROUND

Thymic lipofibroadenomas are extremely rare. In this study, we investigated the clinicopathological characteristics of thymic lipofibroadenomas.

CASE SUMMARY

This study included three patients with thymic lipofibroadenomas. We retrospectively analyzed the patient data to determine the clinicopathological characteristics of thymic lipofibroadenomas. The study included one man and two women [mean age, 43 (33-59) years]. All patients were non-smokers and presented with well-defined anterior mediastinal tumors. The cut surfaces of the tumors were solid, with a mixture of yellow and white areas. Microscopic evaluation of resected specimens showed scattered cord-like structures of epithelial cells embedded within abundant fibrotic and hyaline stroma admixed with variable quantities of adipose tissue. One patient showed hyperplastic thymic tissue in a part of the tumor.

CONCLUSION

Thymic lipofibroadenomas are an extremely rare type of benign thymic tumor. Surgical removal of lipofibroadenomas is usually curative.

Thymic lipofibroadenoma of the anterior mediastinum: A rare case report

BACKGROUND

Lipofibroadenoma is an extremely rare thymic tumor, and the anterior mediastinum is the most common site.

CASE SUMMARY

A 21-year-old male was admitted with fever without obvious cause for 2 months. After admission, the patient's highest temperature was 38.3°C, accompanied by diarrhea. Physical examination showed coarse breath sounds in both lungs. Chest enhanced computed tomography (CT) showed a mass of mixed density shadow on the left side of the anterior mediastinum with a size of approximately 9.2 cm × 5 cm × 2.1 cm and a clear boundary mixed with a low fat density shadow. Mediastinal tumors were removed under general anesthesia by video-assisted thoracoscopic surgery. Macroscopically, a clear boundary was shown between the tumor and the remaining thymus. Microscopically, the tumor contained a large amount of mature adipose and fibrous tissue with scattered cord-like epithelial tissue and a small number of lymphocytes scattered in the stroma. The tumor lacked thymic bodies. The neoplastic epithelial cells were oval or polygonal and arranged in fissures, the nuclei were uniform in size and mild in shape, and mitosis was rare. Epithelial cells were positive for AE1/AE3 and CK19, lymphocytes were positive for CD3 and CD20, and fat and fibrous tissue were positive for S-100 and vimentin, respectively. The Ki67 labeling index was less than 5%. Based on histological features and immunophenotype, thymic lipofibroadenoma was diagnosed. The patient was followed up 1 year after the operation, and no recurrence or residual lesions were found on the X-ray re-examination.

CONCLUSION

Lipofibroadenoma is a benign thymic tumor, and thymectomy is regarded as the best treatment. The biological behavior of thymic lipofibroadenoma is good, and the recurrence rate is low.

Thymofibrolipoma: a case report and review of the literature

Background

Thymofibrolipoma has been described as a variant of thymolipoma. To date, 3 cases have been reported, and the lesion have been described to consist of extensive areas of collagenous tissue interspersed with islands of mature adipose tissue and strands of thymic tissue.

Case presentation

A 43-year-old woman had an anterior mediastinal tumor. Macroscopically, the cut surface of the tumor was composed of a yellowish lipomatous component and a uniform whitish fibrous component with elastic stiffness. Microscopically, the tumor was composed of collagenous fibrous tissue with sparse spindle cells, mature adipocytes and strands or islands of thymic tissue. The spindle cells in the fibrous tissue had monoallelic deletion of the 13q14 region and corresponding loss of RB1 and FOXO1A protein expression.

Conclusions

This case report may strengthen the hypothesis that thymofibrolipoma is a neoplastic lesion and a variant of thymolipoma and that thymofibrolipoma and lipofibroadenoma are different names for the same lesion. The name “lipofibroadenoma” was given to the lesion because of its histological resemblance to fibroadenoma of the mammary gland. However, this name does not reflect the pathogenesis of this lesion, and the name “thymofibrolipoma” would be preferable. It will be necessary to discuss whether lipofibroadenoma should be listed as an independent entity in the WHO classification.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-022-01260-1.

Pure Red Cell Aplasia and Other Haematological Diseases Associated With Thymoma: A Case Series and Systematic Review

Background: Thymoma-associated haematological diseases (HDs), such as pure red cell aplasia (PRCA) and Good's syndrome, are extremely rare, and due to the paucity of large-scale studies, the characteristics, remission after thymectomy, and long-term evaluation remain undetermined.

Methods: We retrospectively assessed patients with thymoma and associated HDs from Jan 2005 to Dec 2020. All patients received thymectomy and/or additional treatments for HDs. A comparison with thymoma-associated myasthenic gravis (MG), and a systematic review from PubMed/MEDLINE and Embase were conducted.

Results: In the median follow-up of 56 months, 130 patients were enrolled. Patients with thymoma-associated MG (n = 46) and HDs [n = 8; PRCA (n = 5), PRCA and Good's syndrome (n = 2) and autoimmune haemolytic anaemia (n = 1)] were evaluated. Patients with MG had a significantly higher remission rate after thymectomy (50 vs. 17%; p = 0.0378) as compared to those with other autoimmune diseases. Two of seven patients with PRCA experienced remission with thymectomy alone, and an additional two patients achieved remission with thymectomy plus immunosuppressive therapy (IST). In the systematic review, 60 studies (case reports, n = 46; case series including the present study, n = 14) were evaluated. Forty-four percent of patients were diagnosed with PRCA after thymoma, and 61% achieved remission with thymectomy plus IST; however, Good's syndrome was unaffected.

Conclusions: Our study indicates that patients with thymoma-associated autoimmune diseases other than MG have a lower remission rate than those with MG. Remission of thymoma-associated PRCA can be achieved by thymectomy and IST. This study provides insight into extremely rare but puzzling autoimmune manifestations.

Giant Intrathoracic Mass in a Young Woman With Acute Kidney Injury

CASE PRESENTATION

A 35-year-old woman without past medical history sought treatment for fatigue and dry cough of 3 weeks' duration. Basic laboratory tests revealed severe anemia. She had no history of bleeding, hemoptysis, dyspnea, or fever. The patient was admitted for RBC transfusion and more extensive diagnostics.

Thymic lipofibroadenoma accompanied with largish calcifications

Thymic lipofibroadenomas are extremely rare; their radiological features have never been reported. We report the first case of a lipofibroadenoma with some largish calcifications mimicking a teratoma. A 28-year-old man had an anterior mediastinal tumor with some calcifications on preoperative computed tomography, which was suspected to be a mature teratoma and resected through robot-assisted thoracic surgery. This tumor had strands of epithelial cells separated by abundant fibrous stroma containing fat cells and was thus diagnosed as a lipofibroadenoma. He was well without any recurrence 6 months postoperatively. Largish calcifications on preoperative computed tomography make distinguishing between teratomas and lipfibroadenomas difficult.

Pure red cell aplasia associated with thymoma: a report of a single-center experience

Background

Pure red cell aplasia (PRCA) associated with thymoma is relatively rare, and relevant reports are limited. We investigated the clinical features and outcomes of PRCA associated with thymoma in this study.

Methods

A retrospective review of all PRCA patients who underwent surgical resection of thymoma from April 1, 2004, to December 31, 2015, was performed.

Results

We experienced eight patients with PRCA among 146 patients who underwent surgical resection of thymoma. Extended thymectomy (n=4) and thymectomy (n=4) were performed for thymoma. Regarding the WHO classification of thymoma, the subtypes were type B2 or B3 in seven patients, and the stage of thymoma was advanced in seven patients. Complete resection was achieved macroscopically in only five patients. Recurrence of thymoma occurred in four patients who underwent complete resection. PRCA was diagnosed after surgical resection of thymoma in six patients (range 1-101 months, median 56.5 months). Cyclosporine was used for PRCA in six patients. Pneumonia of treatment-related complications due to cyclosporine occurred in all patients. The follow-up period ranged from 13-147 months (median 54.5 months) after the PRCA diagnosis. Three patients obtained complete remission of anemia by cyclosporine. Although one patient was able to stop taking cyclosporine because of complete remission of anemia, transfusion was needed due to relapse of PRCA. Five patients died, with the main causes of death diagnosed as pneumonia (n=4) and cardiac failure (n=1).

Conclusions

PRCA associated with thymoma was diagnosed postoperatively in three-quarter of patients. We should be alert for the occurrence of PRCA even after resection of thymoma, especially in patients with incomplete resection or advanced disease. Cyclosporine was effective for PRCA, but treatment-related complications occurred, particularly pneumonia. As treatment for PRCA associated with thymoma and its complications were combined in a complex manner, treating PRCA associated with thymoma can be quite difficult.

Microfluidic-Based Multi-Organ Platforms for Drug Discovery

Development of predictive multi-organ models before implementing costly clinical trials is central for screening the toxicity, efficacy, and side effects of new therapeutic agents. Despite significant efforts that have been recently made to develop biomimetic in vitro tissue models, the clinical application of such platforms is still far from reality. Recent advances in physiologically-based pharmacokinetic and pharmacodynamic (PBPK-PD) modeling, micro- and nanotechnology, and in silico modeling have enabled single- and multi-organ platforms for investigation of new chemical agents and tissue-tissue interactions. This review provides an overview of the principles of designing microfluidic-based organ-on-chip models for drug testing and highlights current state-of-the-art in developing predictive multi-organ models for studying the cross-talk of interconnected organs. We further discuss the challenges associated with establishing a predictive body-on-chip (BOC) model such as the scaling, cell types, the common medium, and principles of the study design for characterizing the interaction of drugs with multiple targets.

Thymoma associated with hypogammaglobulinaemia and pure red cell aplasia

Thymomas are neoplasias that begin in the thymus and develop in the anterior mediastinum. They are commonly associated with a variety of systemic and autoimmune disorders, such as pure red cell aplasia, hypogammaglobulinaemia, pancytopaenia, collagen diseases, and, most commonly, myasthenia gravis. The presence of inter-current infections, especially diarrhoea and pneumonia, in the presence of lymphocyte B depletion and hypogammaglobulinaemia is known as Good’s syndrome and may affect up to 5% of patients with thymoma. While anaemia is present in 50%–86% of patients with Good’s syndrome, only 41.9% of cases present pure red cell aplasia. Concomitance of these two conditions has only been rarely studied.

We report on the case of a 55-year-old man diagnosed with advanced thymoma, who, during the progression of his disease, developed signs and symptoms suggesting Good’s syndrome and pure red cell aplasia. We also performed a brief review of the literature concerning this association, its clinical characteristics, and treatment.

Lipofibroadenoma of the thymus: a case report

We observed an unusual case of Lipofibroadenoma (LFA) in the anterior mediastinum with a 21-year-old man, who was detected with a mass on a chest X-ray scan for one month. Thymothymectomy was then performed and the mass was excised completely, in which the tumor was histologically composed of epithelial cells, lymphocytes, mature adipose and fibrous tissue. Within the tumor, the fat cells was distributed singly or multifocally under the ground of fibro tissue with hyaline degeneration, and the epithelial cells were arranged as crack structure with lymphocytes infiltrated sparsely. By immunohistochemical staining assay, the epithelial cells were positive for AE1/AE3 and CK19, and the lymphocytes were CD3 and CD20 positive. Based on the histological characters, a diagnosis of LFA was made, and the total follow-up period was determined to be forty six months. The final repeated CT scan revealed no recurring or residual lesions were detected during the post-surgical course.

A rare thymoma type presenting as a giant intrathoracic tumor: lipofibroadenoma

Type B1 thymoma (lipofibroadenoma) is extremely rare. The tumor is characterized by an organoid appearance rich in lymphocytes with medullary differentiation and perivascular spaces. A twenty-three-year-old female patient was admitted to our clinic with complaints of chest pain and dyspnea for six months. Chest computed tomography showed solid and fatty components of masses 21×7 and 5×7 cm with clear borders in the right thoracic cavity. The patient underwent a posterolateral thoracotomy in which the mass, arising from the anterior mediastinum, was resected. Histopathological examination showed that the mass was Type B1 thymoma, and the patient was presented in light of the literature.

Pure red cell aplasia and hypogammaglobulinemia in a patient with thymoma

Both pure red cell aplasia (PRCA) and hypogammaglobulinemia are rarer conditions than myasthenia gravis (MG) in thymoma patients. Several articles have discussed the relation between PRCA and thymoma or hypogammaglobulinemia and thymoma, and their proper treatments. Instances of both PRCA and hypogammaglobulinemia in a thymoma patient are few and reported sporadically in the literature. We discuss a 46-year-old woman with thymoma and simultaneous PRCA and hypogammaglobulinemia who achieved complete remission from PRCA after perioperative steroid administration and extended thymectomy, and review the literature.

Ectopic thymoma with pure red cell aplasia--ambiguity with indolence

Two cases of thymomas with pure red cell aplasia (PRCA) are presented, highlighting variability in their anatomic location, ambiguity in presentation, indolence of course and unpredictability of response to treatment. Multi-modality approach is necessary for both diagnosis and management of this combination. Duration and side effects of treatment determine the overall prognosis.

Type AB thymoma accompanied by pure red cell aplasia and Good syndrome with CMV infection of tumor cells

Reported herein is a case of type AB thymoma accompanied by pure red cell aplasia (PRCA) and Good syndrome. The patient was a 55-year-old woman who was found to be anemic and to have an abnormal shadow at the left pulmonary hilus on routine medical examination. Bone marrow aspiration was performed and she was diagnosed as having PRCA. She also had hypogammaglobulinemia. The anemia was temporarily cured with oral prednisolone and cyclosporin A, and the patient underwent total thymectomy. The tumor was type AB thymoma, composed mainly of type A components; widespread spindle cell components showed slight to moderate infiltration of immature T-cells. In addition, CMV inclusion bodies were scattered throughout this tumor. The CMV-infected cells were tumor cells, because they were positive for pancytokeratin and negative for CD34. Several cases of Good syndrome with widespread CMV infection have been reported, but it is extremely rare for CMV-inclusion bodies to be found in tumor cells. No thymoma cases involving CMV infection of tumor cells have been reported.

Pure red cell aplasia associated with thymoma: clinical insights from a 50-year single-institution experience

Acquired pure red cell aplasia (PRCA) is a rare disorder of erythropoiesis that can develop in association with a thymoma. Optimal management of this subgroup is unclear, and there have been few series reporting long-term clinical outcomes. Here, we report features of 13 patients treated for PRCA associated with thymoma over 50 years at our institution. Surgical resection of the thymoma was insufficient for normalisation of erythropoiesis in all cases. T-cell gene rearrangement studies did not routinely demonstrate a clonal process, and ciclosporin and anti-thymocyte globulin were effective adjuvant treatments. However, treatment-related morbidity was high, with frequent infectious complications.

Mediastinum thymoma diagnosed by FNA and ThinPrep technique: a case report

Thymoma is a primary tumor of the thymus epithelial cells. It may be asymptomatic or accompanied with atypical clinical symptoms or paraneoplastic syndromes, such as myasthenia gravis. The biological behavior of thymomas is unpredictable. The invasion of the capsule or the adjacent tissues is the major diagnostic criterion for the malignant behavior of these tumors. This is an interesting case of thymoma diagnosed by fine-needle aspiration biopsy (FNA) and ThinPrep technique, in a 54-year-old female patient with a history of gastric adenocarcinoma. Cytology of the mediastinum mass revealed a mixed population of epithelial cells and lymphocytes. The tumor was excised and the histopathological examination supported the cytological diagnosis. Thymomas commonly constitute a problem in differential diagnosis of mediastinum masses. FNA biopsy in correlation with ThinPrep technique and immunocytochemistry may play a significant role in clarifying the nature of these lesions and may contribute to the early management and choice of the optimal therapeutic manipulation.