Cystic lesion of the thymus. An occasionally malignant cervical and/or anterior mediastinal mass

Between 1965 and 1982, we treated 46 patients with cystic lesions of the thymus. Thirty patients had anterior mediastinal cysts, nine had cysts which were large enough to be both cervical and mediastinal, and seven had cervical cysts. The majority (40/46) presented with asymptomatic masses. Six patients presented with distinct complaints: dysphagia (four patients), hoarseness owing to vocal cord paralysis (one patient), and cervical pain (one patient). All six had benign thymic cysts. The diagnosis of a cystic mass was established prior to operation by ultrasonography and computed axial tomography in our last three patients. These two techniques delineated the capsule and the central fluid in those three cases. All 46 patients had the mass resected without mortality or significant morbidity, except for resection of the phrenic nerve in one patient with malignant cystic thymoma. Cervical cysts were excised through cervical incisions. Cysts located in the anterior mediastinum and cervical-mediastinal cysts required median sternotomy or right thoracotomy for successful resection. Pathological examination showed that 39 patients had benign thymic cysts, three had benign cystic thymoma, two had malignant thymoma, one had a seminoma arising in the thymus, and one had a lymphoblastoma. We believe that a cystic thymic mass which can be detected by ultrasonography and computed tomography, although usually benign, does not eliminate the possibility of malignancy, and resection, therefore, is indicated.     

Technik der Thymuschirurgie

The group of thymic tumors includes thymomas, thymic carcinomas and neuroendocrine thymic tumors (NETT). They are rare tumor entities but represent the majority of malignant tumors of the anterior mediastinum in adult patients. The biological behavior is characterized by slow tissue infiltration and locoregional tumor spread. Complete surgical resection is the foundation of the treatment of thymic tumors. Early tumor stages can be addressed by minimally invasive surgical procedures. In 30?% of patients the tumors already infiltrate additional mediastinal structures, the lungs or the chest wall warranting extended surgical approaches. This review article summarizes the operative approaches available for thoracic surgeons. Knowledge of the available surgical techniques in thymic surgery can be transferred to other mediastinal tumors.     

Low-grade serous carcinoma of the ovary metastatic to the anterior mediastinum simulating multilocular thymic cysts: a clinicopathologic and immunohistochemical study of 3 cases

Three cases of serous borderline tumors of the ovary with areas of serous low-grade carcinoma metastatic to the anterior mediastinum simulating multilocular thymic cysts are presented. The patients are women between the ages of 33 and 50 years. The 3 women had a prior history of primary ovarian neoplasms diagnosed over a period ranging from 3 to 20 years; the 3 patients were in stages IIIA, IIIB, and III. Follow-up radiologic examination revealed the presence of an anterior mediastinal tumor. The 3 patients underwent surgical resection of the mediastinal tumor. Grossly, the mediastinal tumors measured from 7 to 9 cm in greatest diameter and were described as cystic with solid areas. Focal areas of hemorrhage were present, but frank necrosis was not identified. Histologically, all the tumors basically showed similar histopathologic features, namely, those described in multilocular thymic cysts, ie, cystic structures lined by either squamous or low cuboidal epithelium, lymphoid hyperplasia, cholesterol cleft granulomas, and remnants of thymic tissue. In addition, within the cystic structures, there was a neoplastic cellular proliferation with papillary architecture, nuclear atypia, and scattered mitotic figures. Immunohistochemical studies for keratin, MOC31, and CA-125 showed positive staining in tumor cells while placental-like alkaline phosphatase was negative. Two patients remain alive and well after follow-up ranging from 6 to 18 months and 1 patient died of tumor 18 years after initial diagnosis.     

Videothoracoscopy for the management of mediastinal mass lesions

Background: The indications for video-assisted thoracoscopy have steadily expanded during recent years and include now the management of various mediastinal disorders. Methods: Until now we have used videothoracoscopy for the diagnosis or treatment of mediastinal mass lesions in 28 patients. The indication for the procedure was bilateral or unilateral mediastinal adenopathy in 16, a suspected malignant anterior mediastinal mass lesion in six, and a presumable benign tumor of the posterior or anterior mediastinum in six patients. Results: Video-assisted thoracoscopy provided an accurate tissue diagnosis in all patients with adenopathy and in all but one patient with a malignant mass lesion of the anterior mediastinum. It further allowed complete excision of all benign tumors of the anterior or posterior mediastinum. There were no intra- or postoperative complications, but conversion to open thoracotomy was necessary in one patient. Conclusions: Video-assisted thoracoscopy is a valuable adjunct to traditional surgical techniques for the diagnosis of malignant mediastinal disease and may overcome some of the limitations of mediastinoscopy and mediastinotomy. In the future, it may become the procedure of choice for the resection of small benign tumors of the anterior or posterior mediastinum.     

Robotic surgery for mediastinal tumors

BACKGROUND: The surgical approach to mediastinal tumors has changed during the last two decades. Median sternotomies and thoracotomies have been replaced in part by minimally invasive procedures. Aim of this review is to highlight applications of a robotic-assisted approach in mediastinal tumor surgery. METHODS: Review of the current literature. RESULTS: A robotic approach for thymectomy, anterior mediastinal mass resection, pericardial cyst resection, diagnostic sampling of enlarged lymph nodes in the middle mediastinum, resection of benign neurogenic tumors in the posterior mediastinum and esophageal procedures was shown to be feasible. Postoperative outcomes as well as the contraindications and limitations of a robotic approach are discussed. CONCLUSIONS: For appropriate indications minimal invasive surgery with a surgical robot can safely be performed for tumors in the anterior, middle, and posterior compartments of the mediastinum.     

Mediastinoscopy in the treatment of mediastinal cysts.

OBJECTIVE: Primary cysts constitute 25% of all masses in the mediastinum. Because radiological investigations are often inconclusive, many adults require mediastinoscopy, thoracotomy, video-assisted thoracic surgery, or computed tomography-guided transbronchial, transesophageal, or transcutaneous aspiration to confirm the cystic nature of these lesions. Minimally invasive procedures fail when the cyst contents are gelatinous and mucoid (failure to aspirate) or when the cyst wall continues to secrete fluid. Though Pursel reported mediastinoscopic extirpation of benign cysts 35 years ago, it remains a "therapeutic curiosity" with sporadic reports of its usage. We report 2 successful mediastinal cyst extirpations performed as outpatient procedures and review the literature with regards to its management. METHODS: A rigid, 8-mm mediastinoscope was inserted into the anterior mediastinum following the creation of a 2-cm suprasternal incision and dissection along the anterior surface of the trachea. After aspiration, cytology of the contents revealed their benign nature. Right paratracheal cysts in 2 adult males were successfully removed mediastinoscopically by blunt and sharp dissection. RESULTS: Histopathology revealed benign mesothelial cysts in both instances. Both patients had an uncomplicated procedure and were discharged within 23 hours. No other pathology was detected on mediastinoscopy, and follow-up at 3 months and 6 months has revealed no recurrence. CONCLUSION: Mediastinoscopic cyst removal is a minimally invasive procedure with a very low morbidity and mortality rate. Morbidity, recovery, and discharge times are much less than those of more invasive procedures (video-assisted thoracic surgery / thoracotomy). We suggest that it should be the first-choice procedure for the excision of appropriately located benign mediastinal cysts.     

Infrasternal mediastinoscopic surgery for anterior mediastinal masses

Background Infrasternal mediastinoscopic surgery is a new alternative to the thoracoscopic approach for patients with anterior mediastinal masses.Methods We applied this technique to 18 thymectomies, one thymomectomy, and one cystectomy in a total of 20 patients with anterior mediastinal masses and then assessed the surgical results.Results Infrasternal mediastinoscopic surgery was accomplished in 18 of the 20 patients (90%). The pathological diagnoses included 13 Masaoka stage I thymomas, one stage II thymoma, two stage III thymomas, one thymic cyst, one pericardial cyst, one thymic granuloma, and one mature teratoma. Two patients with stage III thymoma required conversion to sternotomy, one for invasion into the innominate vein and the other for invasion into the pericardium. There was no surgically related mortality or complications in any patients.Conclusion Infrasternal mediastinoscopic surgery is safe and feasible for stage I thymoma and other benign tumors in the anterior mediastinum.     

恶性胸腺瘤的外科治疗进展

胸腺肿瘤在所有恶性疾病中占0．2～1．5％，是成人较常见的前纵隔肿瘤之一，大约占50％，其中恶性胸腺瘤约占纵隔肿瘤的8％～10％。目前主要通过WHO胸腺肿瘤组织学分型进行分类，临床上常用Masaoka分期。手术治疗是目前公认的治疗胸腺瘤，尤其是恶性胸腺瘤的主要方法之一。本文对国内外有关恶性胸腺瘤的治疗方法、手术方式及预后进行综述。     

Thymic metastasis of laryngeal cancer

A 70-year-old man visited the Department of Head and Neck Surgery with a chief complaint of dysphagia. A tumor was observed in the epiglottis and vocal cord, and was diagnosed as squamous cell carcinoma by biopsy. Computed tomography (CT) showed a tumor mainly in the vocal cord. CT scans revealed a tumor centered on the vocal cord, with bilateral cervical lymph node metastases and a well-circumscribed 20-mm tumor in the anterior mediastinum. Fluorodeoxyglucose-positron emission tomography (FDG-PET) showed uptake in the primary lesion, left cervical lymph nodes, and anterior mediastinal tumor, which suggested a lymph node metastasis but did not exclude thymoma. The patient underwent video-assisted thoracic surgery (VATS) resection of the anterior mediastinal tumor with total laryngectomy, total thyroidectomy, and bilateral cervical lymph node dissection. The final pathological diagnosis was laryngeal cancer (glottic cancer, pT4aN2M1, pStage IVC) with thymic metastasis (presenting as an anterior mediastinal tumor). Thymic metastasis of laryngeal cancer is rare, and appears difficult to preoperatively differentiate from other mediastinal tumors.     

Video-assisted thoracoscopic management of anterior mediastinal masses

The author reports his personal experience on the management of anterior mediastinal masses using video-assisted thoracoscopic surgery (VATS) at a single institution. From August 1993 to March 1995, 24 patients (14 males and 10 females ranging in age from 9 to 76 years old) with anterior mediastinal masses were diagnosed or treated by VATS. This consisted of 11 biopsies and 13 resections (11 thymectomies and 2 thymic cystectomies). Seven biopsies were performed for primary histological diagnosis (four non-Hodgkin's lymphoma, two metastatic carcinoma, one yolk sac tumor) and four biopsies were performed to detect residual tumors following chemotherapy. Complete thymectomy was accomplished in all 11 cases by examination of the thymic bed and resected specimen. We have reserved this approach for resection of benign masses only. Adequate biopsy for histological diagnosis was obtained in all 11 cases to guide further management. There was no surgical mortality or intraoperative complications. The median postoperative hospital stay for the entire group was 3 days. We conclude that VATS for resection or biopsy of an anterior mediastinal mass is technically feasible and provides an alternative to the conventional approaches in selected patients.     

Surgical strategy for invasive pulmonary and mediastinal tumors requiring superior vena cava reconstruction

During the past 16 years, 22 patients were operated on concomitantly with superior vena cava (SVC) reconstruction in our university hospital. Among them, 19 patients had anterior mediastinal tumor and 3 advanced lung cancer. They were 13 males and 9 females, ranging in age from 16 to 70 (mean, 51.4) years. Severe SVC syndrome was found in 10 cases of them. The anterior mediastinal tumors consisted of invasive thymoma in 10 cases, thymic Hodgkin's disease in 2, seminoma in 2, and thymic cancer, thymic carcinoid, thyroid cancer, metastasis of chondrosarcoma and yolk sac tumor in each one. Regarding SVC reconstruction, anatomical bypass was performed in 18 cases, in addition to a radical resection of the tumor. The left innominate vein was reconstructed in 5, the right innominate vein including SVC in 4 and bilateral veins in 9. Extra-anatomical bypass was performed in 4 cases with unresectable tumors because of severe SVC syndrome. Subclavian-femoral vein bypass was performed in one and internal jugular-femoral vein bypass in 3. In anatomical bypass, 7 cases have been alive now though 11 died, and graft patency rate was 82% in the right and 38% in the left. All 4 cases with extraanatomical bypass showed improvement of SVC syndrome, but died one to seven months postoperatively. In conclusions, radical operation with reconstruction of SVC was effective to long-term survival and improvement of SVC syndrome. Extraanatomical bypass improved postoperative quality of life remarkably.     

Surgical therapy for neuroendocrine tumors of the thymus

Summary. Neuroendocrine tumors of the thymus, also known as thymic carcinoids, are rare tumors of the anterior mediastinum. They occur sporadically or in association with the MEN I syndrome. We present five patients (four male, one female; age of first manifestation 19–53 years) who were operated on at our hospital between 1984 and 1995 for neuroendocrine thymic tumors. A hormone-producing tumor presented with Cushing's syndrome in two patients. Two patients had MEN I syndrome. Only in the female patient the primary tumor was confined to the thymus. We found lymph node metastases in three patients and a distant metastasis in one. The neuroendocrine tumors have a high rate of local recurrences and thus we performed 11 operations using a transthoracic or transsternal approach. Since there was no operative mortality and adjuvant therapies are of limited value, we recommend surgery even in case of recurrence.      

Benign teratomas of the mediastinum

Approximately 8% of all mediastinal tumors are benign teratomas. We reviewed 86 cases of benign teratoma seen at the Mayo Clinic from 1930 through 1981. The mean age of the patients was 28 years and the sex distribution was approximately equal. The most common symptoms were chest, back, or shoulder pain, dyspnea, and cough, but 36% were asymptomatic at the time of presentation. Chest roentgenograms showed a well-circumscribed anterior mediastinal mass which often protruded into one lung field. Detectable calcification was observed in 22 patients: a calcified tumor wall in seven, bone or teeth in the mediastinum of seven, and nonspecific calcifications in eight. Surgical excision remains the best means of diagnosing and treating this benign tumor. Though the tumors are histologically benign, they may present difficult surgical problems because of the vital structures involved. Since 1952 there has been a change in the clinical presentation of patients with this entity: More patients are asymptomatic and have smaller tumors and fewer complications than prior to 1952.     

Surgical Treatment of Mediastinal Cysts: Report on 29 Cases

Aim : Mediastinal cysts are rare, forming 12–18% of all primary mediastinal tumors. The purpose of this study is to evaluate type, clinical properties, treatment modalities, and results of mediastinal cystic neoplasm in the light of available literature.

Patients and methods : We retrospectively investigated 29 patients who were diagnosed and surgically treated for mediastinal cysts in our clinic between January 1996 and May 2011.

Results : Sixteen (55.2%) patients were male and 13 (44.8%) were female. The average age of the patients was 36.5 ± 22.1 (17–77 years old). The mediastinal cysts comprised 11 (37.9%) bronchogenic cysts; seven (24.1%) hydatid cysts; four (13.8%) benign cystic teratomas; three (10.3%) pericardial cysts; one (5.3%) thymic cyst; one (5.3%) cyst of the thoracic duct; one (5.3%) enteric cyst; and one (5.3%) lymphangioma. Approach methods were thoracotomy in 18 (62.1%) cases; video-assisted thoracoscopicsurgery (VATS) in seven (24.1%) cases; median sternotomy in three (10.3%) cases; and anterior mediastinotomy in one case. Postoperative observations during the follow-up period showed chylothorax in one patient; pleural effusion in one patient; and the recurrence of a bronchogenic cyst in one patient five years after the operation. Postoperative mortality did not occur in any case. The average postoperative hospitalization period was 7.3 days (2–14 days).

Conclusion : A surgical approach to mediastinal cysts offers histological analysis, pathological diagnosis, curative treatment, and prevention from complications.     

Surgical analysis of mediastinal lymphangioma--analysis of 7 cases]

Mediastinal lymphangioma is a very rare disease. In this study, we evaluated 7 surgically treated cases of mediastinal lymphangioma. Four males and 3 females with ages ranging from 5 months to 74 years (average 31.4 years) were examined. Four patients were asymptomatic but had abnormal shadows on their chest X-ray. Of the remaining patients, one had hoarseness and another had superior vena cava syndrome and both had dyspnea. The other patient was discovered because of cervical tumor. Multiple lymphangiomas were found in only 2 patients. One patient had 4 tumors and the other had 2 tumors in the mediastinum. Of all lymphangiomas, 2 were found in the superior mediastinum, 2 in the anterior mediastinum, 3 in the median mediastinum and 3 in the posterior mediastinum. All patients had cystic lymphangioma including 1 with capillary lymphangioma and 1 with cavernous lymphangioma. Median sternotomy was performed in 3 of the patients and posterolateral thoracotomy was performed in the remainder. The cervical tumor was removed by local incision. Complete resection of the lymphangiomas was performed and no recurrence was observed after surgery.     

A case of adenocarcinoma of the thymus

A case of adenocarcinoma of the thymus is reported in this paper. To the best of our knowledge, this is the first case of thymic adenocarcinoma in the world literature. A 51-year-old female was admitted to our hospital because of hyperthyroidism and anterior mediastinal tumor. After control of hyperthyroidism, thoracotomy was performed and the tumor was located in the right lobe of the thymus macroscopically. The tumor was extirpated and the specimen was revealed to be multiple thymic cyst with papillo-tubular adenocarcinoma proliferating in one of the cysts. The variability of the lining cells i.e. squamous, cuboidal, columnar, and transitional cell, suggest that the thymic cyst is of congenital origin and the adenacarcinoma is originated from multipotential lining cells of the cyst. She has no evidence of recurrence for 14 years postoperatively, therefore there is almost no possibility of metastasis from other organ to the anterior mediastinum.     

Anterior mediastinotomy for parathyroidectomy

BACKGROUND: Approximately 2% of ectopic parathyroid glands reside within the mediastinum in a location that requires a thoracic approach. METHODS: All patients with mediastinal parathyroid tumors who underwent anterior mediastinotomy were included in this review. RESULTS: Over the course of 16 years, 10 patients with primary hyperparathyroidism underwent anterior mediastinotomy. There were 6 men and 4 women with a median age of 65. Seven patients had undergone at least one previous cervical exploration. Preoperative calcium levels were 11.3 +/- .8 mg/dL. Nine patients had preoperative localization with radionuclide scans and 9 patients also had preoperative computerized tomography or magnetic resonance imaging scans. An abnormal gland was removed in all cases. Nine of 10 patients had normalization of their calcium levels. CONCLUSIONS: Anterior mediastinotomy after preoperative imaging has proven to be a technically feasible, safe, and effective method for the surgical management of patients with sporadic primary hyperparathyroidism and mediastinal parathyroid tumors.     

Surgical management of mediastinal goiter: risk factors for sternotomy

BACKGROUND AND AIMS: Mediastinal goiter constitutes an indication for surgical management. The procedure can most commonly be performed using the cervical access, but at times, a sternotomy or thoracotomy is necessary. The objective of the investigation was to analyze the prevalence and therapeutic results in patients with mediastinal goiter and to assess factors that affect the need of performing sternotomy in the course of mediastinal goiter surgery. MATERIAL AND METHODS: In the years 1984-2004, i.e., over 21 years, 11,849 patients with various types of goiter were operated on in the department. Mediastinal goiter was detected in 88 (0.76%) individuals. The analyzed material included 64 (72.7%) females and 24 (27.3%) males. The age of the patients ranged between 19 to 81 years, with the mean age of 61 +/- 13 years of life. The material was statistically analyzed. Risk factors for sternotomy were assessed using the multidimensional logistic regression method. RESULTS: The highest percentage of mediastinal goiter was noted in patients operated on due to recurrent goiter (3.86%). Goiter situated in the anterior mediastinum was noted in 61 (69.3%) individuals, while 27 (30.7%) patients demonstrated goiter located in the posterior mediastinum; of the latter, nine were previsceral and 18 retrovisceral. In the majority of cases, these were primarily cervical goiters, which descended from the neck to the mediastinum (53 patients). Aberrant adenomas were diagnosed in 32 (36.4%) individuals. Four patients presented with the superior cava vein syndrome. Primary goiters evaluated intraoperatively with blood supply originating from the mediastinal vessels were observed in 12 (13.6%) cases. In 27 (30.7%) patients, sternotomies were necessary. In the majority of cases, these were individuals with goiters showing additional blood supply originating from the mediastinal vessels, patients with aberrant adenomas in the mediastinum, especially in recurrent goiters, or else subjects with goiters situated in the posterior mediastinum as compared to anterior mediastinal goiters. No postoperative mortality during stay in a hospital was noted. CONCLUSIONS: Surgical management of patients with mediastinal goiter is the therapeutic modality that requires considerable experience of the surgical team, performed in specialized centers, and appropriate preoperative diagnostic management. Statistically significant risk factors for sternotomy are as follows: recurrent goiter, primary mediastinal goiter, posterior mediastinal location of goiter, and the presence of an aberrant adenoma situated in the mediastinum.     

Thoracoscopic resection of a thoracic duct cyst that developed during follow-up for a thymic cyst

A 29-year-old man had been diagnosed with an anterior mediastinal cyst 6 years earlier and was undergoing follow-up. At a follow-up visit, a newly developed cystic lesion was found in the middle mediastinum; therefore, the anterior mediastinal cyst and the middle mediastinal cyst were resected by thoracoscopic surgery. It was observed that the middle mediastinal cyst originated from the thoracic duct, and the thoracic duct was clipped. Pathologically, the diagnosis was a thymic cyst of the anterior mediastinum and a thoracic duct cyst of the middle mediastinum. The patient developed chylothorax after surgery, and a second thoracoscopic operation was performed. It revealed that part of the clipping of the caudal thoracic duct was incomplete, and leakage of chyle was observed. Hence, the clipping was performed again. The course after the second surgery was good. Thoracic duct cysts are rare even among mediastinal cysts and thus require caution due to their tendency to expand.     

Mediastinal parathyroid tumors

Mediastinal parathyroid tumors are a frequent cause of failed parathyroid operations. I therefore reviewed my experience with 285 consecutive patients treated surgically for hyperparathyroidism from January 1981 to Dec 31, 1986. Two hundred eighty-eight operations were performed on these patients (246 primary, 38 secondary, one error in diagnosis, and 53 reoperations). Mediastinal parathyroid tumors were present in 64 (22%) of the entire group of 285 patients with hyperparathyroidism, and 20 (38%) of 53 patients requiring reoperation for persistent or recurrent hyperparathyroidism. Fifty-two parathyroid tumors were situated in the anterior mediastinum and 12 were found in the posterior mediastinum; 56 of the mediastinal tumors were removed via a cervical approach. In four patients the mediastinal tumor was a fifth histologically documented parathyroid gland. Mediastinal tumors were identified by preoperative localization studies (ultrasonography, three [16%]; thallium-technetium, five of 17 [29%]; computed tomography, eight of 14 [57%]; magnetic resonance imaging, three of seven [43%]; and selective venous catheterization for parathyroid hormone, ten of 11 [91%]). Awareness of the relatively high occurrence of mediastinal tumors (52 anterior, 12 posterior) should decrease the risk of failed parathyroid operations.