- Email: [email protected]
Does an Anecdote Substantiate Dogma?
1182
CORRESPONDENCE
recurrence is possible without adjuvant RT. The precise role of RT in the adjuvant setting after a complete resection is not clear, and ideally this should be addressed in a randomized trial. Furthermore adjuvant chemotherapy should be investigated in stage III thymomas as most recurrences are pleural, and hence they are not addressed by RT. Cameron D. Wright, MD Division of Thoracic Surgery Massachusetts General Hospital 55 Fruit St Blake 1570, Boston, MA 02114 e-mail: [email protected]
References 1. Cesaretti JA. Adjuvant radiation with modern techniques is the standard of care for stage III thymoma (letter). Ann Thorac Surg 2006;81:1180 –1. 2. Zhu G, He S, Fu X, Jiang G, Liu T. Radiotherapy and prognostic factors for thymoma: a retrospective study of 175 patients. Int J Radiat Oncol Biol Phys. 2004;60(4):1113–9. 3. Kondo K, Monden Y. Therapy for thymic epithelial tumors: a clinical study of 1,320 patients from Japan. Ann Thorac Surg 2003;76:878 – 85. 4. PORT Meta-analysis Trialist Group. Postoperative radiotherapy in non-small cell lung cancer: systematic review and meta-analysis of individual patient data from nine randomized controlled trials. Lancet 1998;352:257– 63.
Does an Anecdote Substantiate Dogma? To the Editor:
MISCELLANEOUS
I read with interest the report by Dr Kattach and colleagues [1] of recurrence of a thymoma in a needle tract. This is of interest because many standard texts continue to carry forward the dogma that thymomas should not be biopsied because of a propensity for seeding of the needle tract, a concept that was put forward nearly 40 years ago [2]. Furthermore, the need to biopsy a thymoma is greater today given the increasing data that preoperative chemotherapy is beneficial for stage II and II thymomas [3, 4]. In the past, there was little need to pursue biopsy of a lesion that had a typical appearance of a resectable thymoma when the treatment of thymoma was primarily surgical. Therefore, evidence regarding the risks of biopsy is of importance. The early statement that thymomas should not be biopsied appears to stem from the observation that pleural and pericardial implants are characteristic features of recurrent disease. However, the hypothesis that these implants are indicative of a high propensity to seeding is undermined by the fact that this pattern of dissemination is characteristic of thymomas that have never been biopsied, resected, or violated in any way [4]. The pattern of dissemination does not appear to be influenced by whether or not a biopsy was performed. Hence, this phenomenon appears to be part of the biologic behavior of thymomas, and not a result of seeding per se. The case reported by Dr Kattach and colleagues [1] marks the third case ever reported of recurrence in a needle tract, to the best of my knowledge after an extensive review of the literature. I have also heard of one additional case that has not been reported. In addition, there are three cases of recurrence in a thoracotomy scar that was used for resection [4]. Thus, the incidence of seeding from either biopsy or resection appears to be rather low. This is despite the fact that many prominent centers have routinely obtained a biopsy of stage II or III © 2006 by The Society of Thoracic Surgeons Published by Elsevier Inc
Ann Thorac Surg 2006;81:1177– 83
thymomas for many years [4]. Furthermore, I would venture that almost all centers perform a biopsy when the tumor is deemed to be unresectable prior to initiation of nonsurgical therapy. It is possible that recurrence at a biopsy site has simply not been reported even though it is common. However, numerous series have not reported such a recurrence despite a high frequency of preoperative biopsy and a focus on recurrence [4, 5]. Perhaps such a recurrence is in fact a late finding, and biopsy has not been commonplace for a long enough period of time. However, this argument is undermined by the fact that many of these series report results over a long period of time [4]. The authors assert that recurrence in the needle tract is usually seen soon after biopsy. Can they provide actual data or a reference demonstrating this? We must strive to have actual data guide our policies, rather than propagation of conjectures that are unsupported. Although this case report is important, the paucity of such a recurrence argues for the safety of biopsy, in my opinion, rather than being an argument to avoid biopsy. Frank C. Detterbeck, MD Section of Thoracic Surgery Yale University, FMB 128 333 Cedar St New Haven, CT 06520-8062 e-mail: [email protected]
References 1. Kattach H, Hasan S, Clelland C, Pillai R. Seeding of stage I thymoma into the chest wall 12 years after needle biopsy. Ann Thorac Surg 2005;79:323– 4. 2. Wilkins EJ, Edmunds LH, Castleman B. Cases of thymoma at the Massachusetts General Hospital. J Thorac Cardiovasc Surg 1966;52:322–30. 3. Kim ES, Putnam JB, Komaki R, et al. Phase II study of a multidisciplinary approach with induction chemotherapy, followed by surgical resection, radiation therapy, and consolidation chemotherapy for unresectable malignant thymomas: final report. Lung Canc 2004;44:369 –79. 4. Detterbeck FC, Parsons AM. Thymic tumors. Ann Thorac Surg 2004;77:1860 –9. 5. Wilkins KB, Sheikh E, Green R, et al. Clinical and pathologic predictors of survival in patients with thymoma. Ann Surg 1999;230:562–74.
Reply To the Editor: We would like to thank Dr Detterbeck [1] for his letter regarding the needle biopsy of thymomas prior to resection. Obtaining tissue for histologic analysis is essential in the management planning of thymomas. Indeed, histologic analysis of the tumor is not only essential to determine its grade, which affects the prognosis of the disease [2], but it is as important in analyzing the margins of the resection, the single most important factor determining the long-term patient survival after surgery [3]. As the majority of these tumors are localized and will be completely resected, histologic analysis of the resected tumor is advocated. However, if tissue analysis is essential for the initial management of the tumor (in advanced stages of the disease or when a nonthymic tumor is highly suspected and therefore an adjuvant or nonsurgical therapy is indicated, or both), open surgical biopsy is the preferred method. It has a much better diagnostic rate, and the rate of complication associated with it is very low. As Dr Detterbeck rightly stated in his extensive review [4], needle biopsy has a low diagnostic success rate (only 60%), and 0003-4975/06/$32.00
CORRESPONDENCE
recurrence is possible without adjuvant RT. The precise role of RT in the adjuvant setting after a complete resection is not clear, and ideally this should be addressed in a randomized trial. Furthermore adjuvant chemotherapy should be investigated in stage III thymomas as most recurrences are pleural, and hence they are not addressed by RT. Cameron D. Wright, MD Division of Thoracic Surgery Massachusetts General Hospital 55 Fruit St Blake 1570, Boston, MA 02114 e-mail: [email protected]
References 1. Cesaretti JA. Adjuvant radiation with modern techniques is the standard of care for stage III thymoma (letter). Ann Thorac Surg 2006;81:1180 –1. 2. Zhu G, He S, Fu X, Jiang G, Liu T. Radiotherapy and prognostic factors for thymoma: a retrospective study of 175 patients. Int J Radiat Oncol Biol Phys. 2004;60(4):1113–9. 3. Kondo K, Monden Y. Therapy for thymic epithelial tumors: a clinical study of 1,320 patients from Japan. Ann Thorac Surg 2003;76:878 – 85. 4. PORT Meta-analysis Trialist Group. Postoperative radiotherapy in non-small cell lung cancer: systematic review and meta-analysis of individual patient data from nine randomized controlled trials. Lancet 1998;352:257– 63.
Does an Anecdote Substantiate Dogma? To the Editor:
MISCELLANEOUS
I read with interest the report by Dr Kattach and colleagues [1] of recurrence of a thymoma in a needle tract. This is of interest because many standard texts continue to carry forward the dogma that thymomas should not be biopsied because of a propensity for seeding of the needle tract, a concept that was put forward nearly 40 years ago [2]. Furthermore, the need to biopsy a thymoma is greater today given the increasing data that preoperative chemotherapy is beneficial for stage II and II thymomas [3, 4]. In the past, there was little need to pursue biopsy of a lesion that had a typical appearance of a resectable thymoma when the treatment of thymoma was primarily surgical. Therefore, evidence regarding the risks of biopsy is of importance. The early statement that thymomas should not be biopsied appears to stem from the observation that pleural and pericardial implants are characteristic features of recurrent disease. However, the hypothesis that these implants are indicative of a high propensity to seeding is undermined by the fact that this pattern of dissemination is characteristic of thymomas that have never been biopsied, resected, or violated in any way [4]. The pattern of dissemination does not appear to be influenced by whether or not a biopsy was performed. Hence, this phenomenon appears to be part of the biologic behavior of thymomas, and not a result of seeding per se. The case reported by Dr Kattach and colleagues [1] marks the third case ever reported of recurrence in a needle tract, to the best of my knowledge after an extensive review of the literature. I have also heard of one additional case that has not been reported. In addition, there are three cases of recurrence in a thoracotomy scar that was used for resection [4]. Thus, the incidence of seeding from either biopsy or resection appears to be rather low. This is despite the fact that many prominent centers have routinely obtained a biopsy of stage II or III © 2006 by The Society of Thoracic Surgeons Published by Elsevier Inc
Ann Thorac Surg 2006;81:1177– 83
thymomas for many years [4]. Furthermore, I would venture that almost all centers perform a biopsy when the tumor is deemed to be unresectable prior to initiation of nonsurgical therapy. It is possible that recurrence at a biopsy site has simply not been reported even though it is common. However, numerous series have not reported such a recurrence despite a high frequency of preoperative biopsy and a focus on recurrence [4, 5]. Perhaps such a recurrence is in fact a late finding, and biopsy has not been commonplace for a long enough period of time. However, this argument is undermined by the fact that many of these series report results over a long period of time [4]. The authors assert that recurrence in the needle tract is usually seen soon after biopsy. Can they provide actual data or a reference demonstrating this? We must strive to have actual data guide our policies, rather than propagation of conjectures that are unsupported. Although this case report is important, the paucity of such a recurrence argues for the safety of biopsy, in my opinion, rather than being an argument to avoid biopsy. Frank C. Detterbeck, MD Section of Thoracic Surgery Yale University, FMB 128 333 Cedar St New Haven, CT 06520-8062 e-mail: [email protected]
References 1. Kattach H, Hasan S, Clelland C, Pillai R. Seeding of stage I thymoma into the chest wall 12 years after needle biopsy. Ann Thorac Surg 2005;79:323– 4. 2. Wilkins EJ, Edmunds LH, Castleman B. Cases of thymoma at the Massachusetts General Hospital. J Thorac Cardiovasc Surg 1966;52:322–30. 3. Kim ES, Putnam JB, Komaki R, et al. Phase II study of a multidisciplinary approach with induction chemotherapy, followed by surgical resection, radiation therapy, and consolidation chemotherapy for unresectable malignant thymomas: final report. Lung Canc 2004;44:369 –79. 4. Detterbeck FC, Parsons AM. Thymic tumors. Ann Thorac Surg 2004;77:1860 –9. 5. Wilkins KB, Sheikh E, Green R, et al. Clinical and pathologic predictors of survival in patients with thymoma. Ann Surg 1999;230:562–74.
Reply To the Editor: We would like to thank Dr Detterbeck [1] for his letter regarding the needle biopsy of thymomas prior to resection. Obtaining tissue for histologic analysis is essential in the management planning of thymomas. Indeed, histologic analysis of the tumor is not only essential to determine its grade, which affects the prognosis of the disease [2], but it is as important in analyzing the margins of the resection, the single most important factor determining the long-term patient survival after surgery [3]. As the majority of these tumors are localized and will be completely resected, histologic analysis of the resected tumor is advocated. However, if tissue analysis is essential for the initial management of the tumor (in advanced stages of the disease or when a nonthymic tumor is highly suspected and therefore an adjuvant or nonsurgical therapy is indicated, or both), open surgical biopsy is the preferred method. It has a much better diagnostic rate, and the rate of complication associated with it is very low. As Dr Detterbeck rightly stated in his extensive review [4], needle biopsy has a low diagnostic success rate (only 60%), and 0003-4975/06/$32.00