CASE REPORTS
Thoracoscopic Resection of an Anterior Mediastinal Tumor Rodney J. Landreneau, MD, Robert D. Dowling, MD, William M. Castillo, MD, and Peter F. Ferson, MD Section of Thoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
The therapeutic role of thoracoscopy has expanded with advances in endoscopic surgical instrumentation and laser technology. We report a complete thoracoscopic resection of an encapsulated (stage I) thymoma with lymphocytic predominance in an elderly woman without myasthenia gravis. The patient had an uncomplicated
postoperative course and was discharged on the third postoperative day. Median steinotomy with its attendant morbidity was avoided. Thoracoscopic resection of thymic neoplasms may be a useful approach in carefully selected patients. (Ann Thorac Surg 1992;54:1424)
R
identified. Retraction of the collapsed lung away from the mediastinum revealed the lesion within the thymus anterior to the pericardium (Fig 2). Four more trocar sites were used to allow the introduction of endoscopic instruments (Fig 3). The lesion was firm to palpation and appeared well circumscribed and free from surrounding structures. The endoscopic forceps were introduced to grasp the normal thymic tissue adjacent to the lesion. Endoscopic scissors were then used to sharply develop a discrete plane between the pericardium and the thymic tissue. The blood supply of the tumor arising from the internal mammary vessels was identified at the cephalic aspect of the lesion and ligated with endoscopic clips (Autosuture Endoscopic Clip ML, No. 176615; United States Surgical Corp). By alternating the position of the thoracoscope and the endoscopic instruments between the trocar sites, complete dissection of the thymoma was accomplished under endoscopic vision. The tumor was placed in a surgical glove that was introduced into the chest through one of the trocar sites. The axillary trocar site was slightly enlarged to allow removal of the intact gloved specimen (Fig 4). Frozen section pathologic analysis revealed a completely encapsulated, epithelial thymoma with lymphocytic predominance. Chest tube drainage was established through one trocar site, and the other trocar sites were closed with absorbable suture. The total operative time was 245 minutes. The patient’s postoperative course was uneventful. The chest tube was removed 1 day after operation. She was discharged on the morning of the third postoperative day. The patient required only nonsteroidal analgesics to manage mild incisional discomfort after operation. A chest roentgenogram obtained on the day of discharge was normal. The patient resumed full activity 5 days after operation. We will continue to closely follow up this patient. She remains well without delayed morbidity 3 months after operation.
ecent advances in endoscopic surgical instrumentation have expanded the role of thoracoscopy to include resection of apical bullae, pleura-based lesions, and some pulmonary nodules [l, 21. Experience gained with these resections allowed for a successful thoracoscopic resection of an encapsulated (stage I) thymoma. A 69-year-old woman reported a mild, intermittent nonproductive cough of 10 months’ duration. The patient denied weakness, fatigue, fevers, sweats, weight loss, or other systemic symptoms. Physical examination was unremarkable. A chest roentgenogram revealed a soft tissue density in the anterior mediastinum. Contrast-enhanced computed tomography of the chest confirmed a 5.0-cm mass in the left anterior mediastinum without evidence of local invasion (Fig 1). Scintigraphic scan of the thyroid and pulmonary function studies were normal. Acetylcholine receptor antibody test was negative. The patient was referred for resection of a presumed thymic tumor. Due to the lateral location of the lesion and the absence of local invasion shown by computed tomography, thoracoscopic examination was undertaken to further stage and possibly resect this tumor. An initial bronchoscopic examination revealed no abnormalities. A double-lumen endotracheal tube was used to allow collapse of the left lung. A trocar 11 mm in diameter (Autosuture Surgiport Trocars; United States Surgical Corp, Norwalk, CT) was introduced into the left thoracic cavity through the fourth intercostal space at the midaxillary line. The thoracoscope (Operating wide angle zero degree Hopkin’s telescope, No. 26040A; Karl Storz Endoscopic America Inc, Culver City, CA) was introduced through this trocar for exploration of the pleural cavity. No abnormalities of the left lung or pleural surfaces were Accepted for publication Nov 22, 1991 Address reprint requests to Dr Landreneau, Section of Thoracic Surgery, University of Pittsburgh, Montefiore University Hospital, Fifth Floor East, 3459 Fifth Ave, Pittsburgh, PA 15213.
0 1992 by The Society of Thoracic Surgeons
0003-4975/92/$5.00
Ann Thorac Surg 1992;54:1 4 2 4
Fig 1 . Computed tornogram of the chest reveals an anterior mediastinal mass 5.0 cm in diameter.
Comment
CASE REPORT LANDRENEAU ET AL THORACOSCOPIC THYMOMA RESECTION
143
Fig 3 . Positions of the trocars used during thoracoscopic resection of the thymic lesion.
The role of thoracoscopy as a therapeutic modality has rapidly expanded as improvements are made in endoscopic surgical equipment [2]. Thoracoscopic management of apical bullous disease and resection of peripheral pulmonary nodules have been reported [l, 21. Despite intense investigation, the pathophysiology and appropriate treatment for thymomas is still subject to debate [>8]. The primary goal in the management of thymic tumors is removal of all pathologic tissue [%8]. The findings at operation primarily define the clinical stage of thymomas and the magnitude of the resection required to control the tumor [3-5, 71. Stage I lesions are those without tumor invasion of the thymic capsule, whereas stage I1 lesions have violated the capsule or the pleura. Stage 111 tumors are those with invasion of surrounding tissues, and stage IV lesions represent disseminated disease [4]. In a select group of patients found to have an anterior mediastinal mass without evidence of local invasion on computed tomography, exploratory thoracoscopy may be
considered. If thoracoscopy fails to reveal intrathoracic .. metastases or local invasion, thoracoscopic resection of the entire lesion may be undertaken. If pathologic analysis confirms the presence of stage I thymoma, thoracoscopic resection of the lesion would constitute definitive operative therapy. In the event of more advanced disease, we would still favor a more radical operative approach through a thoracotomy or sternotomy. We chose an initial thoracoscopic approach to this patient's anterior mediastinal process because of the above considerations. We also hoped to avoid the potential perioperative morbidity related to sternotomy or formal thoracotomy. Most authorities agree that resection of the entire thymus is the standard operative approach for thymoma associated with myasthenia gravis [B]. For patients with thymoma not associated with myasthenia gravis, surgical therapy is dictated by the findings at operation. For stage I lesions, disease-free survival can be expected in approximately 98% of patients with excision of the lesion [3, 5, 71. Immediate pathological analysis to confirm the absence of
Fig 2. Anterior mediastinal mass as seen in the left pleural cavity through the thoracoscope.
Fig 4 . Surgical glove containing the thymic tumor being removed from the thoracic cavity through an axillavy trocav site.
144
CASE REPORT LANDRENEAU ET AL THORACOSCOPIC THYMOMA RESECTION
invasion is essential in these patients [6, 7, 81. Postoperative radiotherapy, not immediate reexploration, is usually recommended for patients found to have capsular invasion unrecognized at operation [8]. If delayed reresection becomes necessary, Kirschner [6] has shown that this can be accomplished in most patients. For patients with more advanced lesions a more extensive operative approach that includes resection of the tumor and, if possible, involved adjacent structures is indicated [ 8 ] . If during the course of exploratory thoracoscopy or endoscopic dissection such a lesion is revealed, we recommend conversion to formal thoracotomy or median sternotomy to accomplish the resection. In summary, a thoracoscopic resection of a stage I thymoma is reported. We believe that for a select group of patients with thymoma, thoracoscopic resection may be adequate operative therapy. We stress that for patients with myasthenia gravis or more advanced disease, total thymectomy with complete excision of the tumor constitutes the standard operative approach. Reduced operative time and more formal indications for this approach will certainly emerge as experience is gained with thoracoscope-assisted thoracic surgery.
Ann Thorac Surg 1992;54:1 4 2 4
References 1. Wakabayashi A, Brenner M, Wilson AF, Tadir Y, Berns M. Thoracoscopic treatment of spontaneous pneumothorax using carbon dioxide laser. Ann Thorac Surg 1990;50:78&90. 2. Landreneau RJ, Herlan DB, Johnson JA, Boley TM, Nawarawong W, Ferson PF. Thoracoscopic neodymium:yttriumaluminum garnet laser-assisted pulmonary resection. Ann Thorac Surg 1991;52:117&8. 3. Fechner RE. Recurrence of noninvasive thymomas. Cancer 1969;23:142?-7. 4. Masaoka A, Monden Y, Nakahara K, Tanioka T. Follow-up study of thymoma with special reference to their clinical stages. Cancer 1981;48:2485-92.. 5. Verley JM, Hollmann KH. Thymoma. A comparative study of clinical stages, histologic features, and survival in 200 cases. Cancer 1985;55:1074-86. 6. Kirschner PA. Reoperation for thymoma: report of 23 cases. Ann Thorac Surg 1990;49:550-5. 7. Pescarmona E, Rendina EA, Ventura F, et al. Analysis of prognostic factors and clinicopathological staging of thymoma. Ann Thorac Surg 1990;50:534,8. 8. Wilkins EW Jr, Grillo HC, Scannell JG, Moncure AC, Mathisen DJ. Role of staging in prognosis and management of thymoma. Ann Thorac Surg 1991;51:888-92.
INVITED COMMENTARY Video thoracic surgery is a new and exciting adjunct in the management of intrathoracic disease, the full potential of which has not yet been fully realized. Clearly, diagnosis and therapy are at the opposite ends of the video thoracic surgery management spectrum, and it is imperative that general thoracic surgeons not confuse these two issues. Reliable diagnosis, which is readily obtainable with video thoracic surgery, does not translate into adequate treatment. Most importantly, video thoracic surgery resection, which by its very nature is limited, must not compromise long-term survival achievable with thoracotomy. This case report illustrates these issues. This lesion was readily diagnosed with video thoracic surgery, but was the patient adequately treated? Although a limited resection is satisfactory for benign nonneoplastic thymic disease, there is no evidence that this is the situation for a thymoma that has the full potential for local recurrence and subsequent invasion. How much thymus then should have been removed? This, too, is not easily answered, but traditionally the gold standard has been thymectomy. Is
this excessive? The literature would say no. To prove otherwise, however, requires careful documentation and long-term follow-up. Many questions must be answered, not the least of which are how is local invasion detected thoracoscopically before the lesion is resected; does the compromised thoracoscopic exposure increase the possibility of microscopic residual; how far should the line of resection be from the thymoma; and when should a thoracotomy be performed? Only time will resolve these issues, but all of these questions must be satisfactorily answered before concluding that resection accomplished with video thoracic surgery is an effective alternative method of treatment.
Peter C . Pairolero, M D Section of General Thoracic Surgey Mayo Clinic Rochester, M N 55905
Thoracoscopic Resection of an Anterior Mediastinal Tumor Rodney J. Landreneau, MD, Robert D. Dowling, MD, William M. Castillo, MD, and Peter F. Ferson, MD Section of Thoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
The therapeutic role of thoracoscopy has expanded with advances in endoscopic surgical instrumentation and laser technology. We report a complete thoracoscopic resection of an encapsulated (stage I) thymoma with lymphocytic predominance in an elderly woman without myasthenia gravis. The patient had an uncomplicated
postoperative course and was discharged on the third postoperative day. Median steinotomy with its attendant morbidity was avoided. Thoracoscopic resection of thymic neoplasms may be a useful approach in carefully selected patients. (Ann Thorac Surg 1992;54:1424)
R
identified. Retraction of the collapsed lung away from the mediastinum revealed the lesion within the thymus anterior to the pericardium (Fig 2). Four more trocar sites were used to allow the introduction of endoscopic instruments (Fig 3). The lesion was firm to palpation and appeared well circumscribed and free from surrounding structures. The endoscopic forceps were introduced to grasp the normal thymic tissue adjacent to the lesion. Endoscopic scissors were then used to sharply develop a discrete plane between the pericardium and the thymic tissue. The blood supply of the tumor arising from the internal mammary vessels was identified at the cephalic aspect of the lesion and ligated with endoscopic clips (Autosuture Endoscopic Clip ML, No. 176615; United States Surgical Corp). By alternating the position of the thoracoscope and the endoscopic instruments between the trocar sites, complete dissection of the thymoma was accomplished under endoscopic vision. The tumor was placed in a surgical glove that was introduced into the chest through one of the trocar sites. The axillary trocar site was slightly enlarged to allow removal of the intact gloved specimen (Fig 4). Frozen section pathologic analysis revealed a completely encapsulated, epithelial thymoma with lymphocytic predominance. Chest tube drainage was established through one trocar site, and the other trocar sites were closed with absorbable suture. The total operative time was 245 minutes. The patient’s postoperative course was uneventful. The chest tube was removed 1 day after operation. She was discharged on the morning of the third postoperative day. The patient required only nonsteroidal analgesics to manage mild incisional discomfort after operation. A chest roentgenogram obtained on the day of discharge was normal. The patient resumed full activity 5 days after operation. We will continue to closely follow up this patient. She remains well without delayed morbidity 3 months after operation.
ecent advances in endoscopic surgical instrumentation have expanded the role of thoracoscopy to include resection of apical bullae, pleura-based lesions, and some pulmonary nodules [l, 21. Experience gained with these resections allowed for a successful thoracoscopic resection of an encapsulated (stage I) thymoma. A 69-year-old woman reported a mild, intermittent nonproductive cough of 10 months’ duration. The patient denied weakness, fatigue, fevers, sweats, weight loss, or other systemic symptoms. Physical examination was unremarkable. A chest roentgenogram revealed a soft tissue density in the anterior mediastinum. Contrast-enhanced computed tomography of the chest confirmed a 5.0-cm mass in the left anterior mediastinum without evidence of local invasion (Fig 1). Scintigraphic scan of the thyroid and pulmonary function studies were normal. Acetylcholine receptor antibody test was negative. The patient was referred for resection of a presumed thymic tumor. Due to the lateral location of the lesion and the absence of local invasion shown by computed tomography, thoracoscopic examination was undertaken to further stage and possibly resect this tumor. An initial bronchoscopic examination revealed no abnormalities. A double-lumen endotracheal tube was used to allow collapse of the left lung. A trocar 11 mm in diameter (Autosuture Surgiport Trocars; United States Surgical Corp, Norwalk, CT) was introduced into the left thoracic cavity through the fourth intercostal space at the midaxillary line. The thoracoscope (Operating wide angle zero degree Hopkin’s telescope, No. 26040A; Karl Storz Endoscopic America Inc, Culver City, CA) was introduced through this trocar for exploration of the pleural cavity. No abnormalities of the left lung or pleural surfaces were Accepted for publication Nov 22, 1991 Address reprint requests to Dr Landreneau, Section of Thoracic Surgery, University of Pittsburgh, Montefiore University Hospital, Fifth Floor East, 3459 Fifth Ave, Pittsburgh, PA 15213.
0 1992 by The Society of Thoracic Surgeons
0003-4975/92/$5.00
Ann Thorac Surg 1992;54:1 4 2 4
Fig 1 . Computed tornogram of the chest reveals an anterior mediastinal mass 5.0 cm in diameter.
Comment
CASE REPORT LANDRENEAU ET AL THORACOSCOPIC THYMOMA RESECTION
143
Fig 3 . Positions of the trocars used during thoracoscopic resection of the thymic lesion.
The role of thoracoscopy as a therapeutic modality has rapidly expanded as improvements are made in endoscopic surgical equipment [2]. Thoracoscopic management of apical bullous disease and resection of peripheral pulmonary nodules have been reported [l, 21. Despite intense investigation, the pathophysiology and appropriate treatment for thymomas is still subject to debate [>8]. The primary goal in the management of thymic tumors is removal of all pathologic tissue [%8]. The findings at operation primarily define the clinical stage of thymomas and the magnitude of the resection required to control the tumor [3-5, 71. Stage I lesions are those without tumor invasion of the thymic capsule, whereas stage I1 lesions have violated the capsule or the pleura. Stage 111 tumors are those with invasion of surrounding tissues, and stage IV lesions represent disseminated disease [4]. In a select group of patients found to have an anterior mediastinal mass without evidence of local invasion on computed tomography, exploratory thoracoscopy may be
considered. If thoracoscopy fails to reveal intrathoracic .. metastases or local invasion, thoracoscopic resection of the entire lesion may be undertaken. If pathologic analysis confirms the presence of stage I thymoma, thoracoscopic resection of the lesion would constitute definitive operative therapy. In the event of more advanced disease, we would still favor a more radical operative approach through a thoracotomy or sternotomy. We chose an initial thoracoscopic approach to this patient's anterior mediastinal process because of the above considerations. We also hoped to avoid the potential perioperative morbidity related to sternotomy or formal thoracotomy. Most authorities agree that resection of the entire thymus is the standard operative approach for thymoma associated with myasthenia gravis [B]. For patients with thymoma not associated with myasthenia gravis, surgical therapy is dictated by the findings at operation. For stage I lesions, disease-free survival can be expected in approximately 98% of patients with excision of the lesion [3, 5, 71. Immediate pathological analysis to confirm the absence of
Fig 2. Anterior mediastinal mass as seen in the left pleural cavity through the thoracoscope.
Fig 4 . Surgical glove containing the thymic tumor being removed from the thoracic cavity through an axillavy trocav site.
144
CASE REPORT LANDRENEAU ET AL THORACOSCOPIC THYMOMA RESECTION
invasion is essential in these patients [6, 7, 81. Postoperative radiotherapy, not immediate reexploration, is usually recommended for patients found to have capsular invasion unrecognized at operation [8]. If delayed reresection becomes necessary, Kirschner [6] has shown that this can be accomplished in most patients. For patients with more advanced lesions a more extensive operative approach that includes resection of the tumor and, if possible, involved adjacent structures is indicated [ 8 ] . If during the course of exploratory thoracoscopy or endoscopic dissection such a lesion is revealed, we recommend conversion to formal thoracotomy or median sternotomy to accomplish the resection. In summary, a thoracoscopic resection of a stage I thymoma is reported. We believe that for a select group of patients with thymoma, thoracoscopic resection may be adequate operative therapy. We stress that for patients with myasthenia gravis or more advanced disease, total thymectomy with complete excision of the tumor constitutes the standard operative approach. Reduced operative time and more formal indications for this approach will certainly emerge as experience is gained with thoracoscope-assisted thoracic surgery.
Ann Thorac Surg 1992;54:1 4 2 4
References 1. Wakabayashi A, Brenner M, Wilson AF, Tadir Y, Berns M. Thoracoscopic treatment of spontaneous pneumothorax using carbon dioxide laser. Ann Thorac Surg 1990;50:78&90. 2. Landreneau RJ, Herlan DB, Johnson JA, Boley TM, Nawarawong W, Ferson PF. Thoracoscopic neodymium:yttriumaluminum garnet laser-assisted pulmonary resection. Ann Thorac Surg 1991;52:117&8. 3. Fechner RE. Recurrence of noninvasive thymomas. Cancer 1969;23:142?-7. 4. Masaoka A, Monden Y, Nakahara K, Tanioka T. Follow-up study of thymoma with special reference to their clinical stages. Cancer 1981;48:2485-92.. 5. Verley JM, Hollmann KH. Thymoma. A comparative study of clinical stages, histologic features, and survival in 200 cases. Cancer 1985;55:1074-86. 6. Kirschner PA. Reoperation for thymoma: report of 23 cases. Ann Thorac Surg 1990;49:550-5. 7. Pescarmona E, Rendina EA, Ventura F, et al. Analysis of prognostic factors and clinicopathological staging of thymoma. Ann Thorac Surg 1990;50:534,8. 8. Wilkins EW Jr, Grillo HC, Scannell JG, Moncure AC, Mathisen DJ. Role of staging in prognosis and management of thymoma. Ann Thorac Surg 1991;51:888-92.
INVITED COMMENTARY Video thoracic surgery is a new and exciting adjunct in the management of intrathoracic disease, the full potential of which has not yet been fully realized. Clearly, diagnosis and therapy are at the opposite ends of the video thoracic surgery management spectrum, and it is imperative that general thoracic surgeons not confuse these two issues. Reliable diagnosis, which is readily obtainable with video thoracic surgery, does not translate into adequate treatment. Most importantly, video thoracic surgery resection, which by its very nature is limited, must not compromise long-term survival achievable with thoracotomy. This case report illustrates these issues. This lesion was readily diagnosed with video thoracic surgery, but was the patient adequately treated? Although a limited resection is satisfactory for benign nonneoplastic thymic disease, there is no evidence that this is the situation for a thymoma that has the full potential for local recurrence and subsequent invasion. How much thymus then should have been removed? This, too, is not easily answered, but traditionally the gold standard has been thymectomy. Is
this excessive? The literature would say no. To prove otherwise, however, requires careful documentation and long-term follow-up. Many questions must be answered, not the least of which are how is local invasion detected thoracoscopically before the lesion is resected; does the compromised thoracoscopic exposure increase the possibility of microscopic residual; how far should the line of resection be from the thymoma; and when should a thoracotomy be performed? Only time will resolve these issues, but all of these questions must be satisfactorily answered before concluding that resection accomplished with video thoracic surgery is an effective alternative method of treatment.
Peter C . Pairolero, M D Section of General Thoracic Surgey Mayo Clinic Rochester, M N 55905
