Surgical resection of a giant thymolipoma causing respiratory failure: A case report

Giant anterior mediastinal thymolipoma: A rare case of thoracoscopic resection and surgical management challenges

INTRODUCTION

Thymolipoma is a rare benign anterior mediastinal tumor composed of thymic and adipose tissues. Early diagnosis and accurate surgical management are crucial to prevent misdiagnosis and optimize patient outcomes.

CASE PRESENTATION

A 17-year-old male with no significant medical history presented to our thoracic surgery department with exertional dyspnea and a sensation of chest tightness. Given the worsening symptoms, a chest computed tomography (CT) scan was performed, revealing a well-circumscribed anterior mediastinal mass in the right paracardiac region, predominantly composed of fatty tissue. The patient underwent right thoracoscopic surgery, during which the tumor was successfully resected. The postoperative course was uneventful. Histopathological examination confirmed the diagnosis of a thymolipoma.

DISCUSSION

Thymolipomas are rare benign tumors composed of mature adipose tissue and thymic tissue, typically located in the anterior mediastinum. They account for less than 9 % of all thymic tumors and are often discovered incidentally. Patients with thymolipomas may present with nonspecific symptoms, such as dyspnea, chest pain, or recurrent respiratory infections, depending on the size and compressive effects of the tumor. Imaging plays a crucial role in identifying thymolipomas, with CT scan often showing a well-encapsulated mass with fat and soft tissue components. Complete surgical resection remains the cornerstone of treatment, ensuring both accurate diagnosis and symptomatic relief.

CONCLUSION

This case underlines the exceptional presentation of a thymolipoma, emphasizing its rarity and the critical role of surgical management in achieving optimal outcomes. Early recognition and intervention are crucial, especially for large or symptomatic lesions.

Defining "Giant" Mediastinal Tumors: Proposal of a New Clinical-Radiological Classification and Case Report

Background/Objectives: Mediastinal tumors, regardless of their location, can grow to significant sizes, causing compression-related symptoms. The term "giant" mediastinal tumor is inconsistently defined in the literature. This study presents a new clinical-radiological classification (CRC) for mediastinal tumors and evaluates its applicability through a systematic review and a detailed case analysis of a giant thymolipoma. Methods: A systematic review of the literature from the past decade was conducted using PubMed to identify relevant studies on "giant" mediastinal tumors. The inclusion criteria focused on studies involving adult patients with documented tumor size and symptomatology. The review identified 22 studies, with most anterior mediastinal tumors classified as CRC 3 (81%), indicating "giant" tumors. Thymolipomas accounted for 58% of these cases. Tumor volume and weight correlated with symptom severity, guiding surgical approaches. The proposed CRC effectively standardized the definition of "giant" tumors. The case analysis of a 6.84 kg thymolipoma highlighted the challenges of surgical resection, confirming the importance of tailored surgical strategies for large tumors. Results: The review of the literature revealed a significant variation in tumor size and weight across the different mediastinal compartments. Symptomatic tumors (CRC stage 3) located in the anterior mediastinum exhibited the largest volumes and weights, with an average volume of 4949 mL (range: 2013-8840 mL) and an average weight of 4137 g (range: 1575-7500 g). In comparison, tumors in the posterior mediastinum ranked second in terms of size, with an average volume of 2128 mL (range: 1040-5460 mL) and an average weight of 2489 g (range: 1009-6000 g). Tumors located in the middle mediastinum were considerably smaller, with an average volume of 536 mL (range: 21-1092 mL). Among the largest symptomatic tumors in the anterior mediastinum, thymolipomas were the most frequently observed histologic type. These findings underscore a clear size gradient across the mediastinal compartments, with the anterior mediastinum harboring the largest symptomatic tumors, followed by the posterior mediastinum, and the smallest tumors in the middle mediastinum. Conclusions: The novelty of the study lies mainly in the new clinical-radiological classification (CRC) of mediastinal tumors. This classification integrates clinical presentation and cross-sectional imaging findings, offering a standardized framework for tumor reporting. In addition, it provides a precise definition of "giant" mediastinal tumors. The findings emphasize the need for early surgical intervention to prevent severe symptoms and complications. This study also showcases the largest enbloc-resected thymolipoma reported in the recent literature, supporting the utility of the proposed classification in clinical practice.

Perioperative strategies and management of giant anterior mediastinal tumors: a narrative review

Background and Objective

Giant anterior mediastinal tumors sometimes may cause circulatory collapse and respiratory failure, known as mediastinal mass syndrome (MMS). The prediction and prevention of MMS is challenging. The aim of this study is to summarize the evaluation methods for MMS and formulate treatment strategies for giant anterior mediastinal tumors.

Methods

We performed a thorough analysis of recent international literature on giant anterior mediastinal tumors (>10 cm in diameter) and MMS published in the PubMed database. The search spanned the duration of the preceding 10 years from August 19, 2023, and only studies published in English were included.

Key Content and Findings

Mature teratomas and liposarcomas are the most common giant anterior mediastinal tumors and MMS develops most frequently in case of malignant lymphomas. Here, we propose a new treatment strategy for giant anterior mediastinal tumors. Based on imaging findings, giant anterior mediastinal tumors can be classified as cystic or solid and further blood investigation data are useful for a definitive diagnosis. When malignant lymphoma or malignant germ cell tumor is highly suspected, the first choice of treatment is not surgery but chemotherapy and radiotherapy. Moreover, image-guided drainage may be effective if giant cystic anterior tumors develop into MMS. The risk classification of MMS is important for treating giant anterior mediastinal tumors. If the MMS risk classification is 'unsafe' or 'uncertain', the intraoperative management deserves special attention. The surgical approach should however be based on tumor localization and invasion of surrounding tissues. Multidisciplinary team coordination is indispensable in the treatment of giant anterior mediastinal tumors.

Conclusions

When giant anterior mediastinal tumors are encountered, it is important to follow the appropriate treatment strategy, focusing on the development of MMS based on imaging findings and symptoms.