Carta Acesso aberto Revisado por pares

Does an Anecdote Substantiate Dogma?

2006; Elsevier BV; Volume: 81; Issue: 3 Linguagem: Inglês

10.1016/j.athoracsur.2005.05.042

ISSN

1552-6259

Autores

Frank C. Detterbeck,

Tópico(s)

Pituitary Gland Disorders and Treatments

Resumo

I read with interest the report by Dr Kattach and colleagues [1Kattach 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: 323-324Abstract Full Text Full Text PDF PubMed Scopus (21) Google Scholar] 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 [2Wilkins E.J. Edmunds L.H. Castleman B. Cases of thymoma at the Massachusetts General Hospital.J Thorac Cardiovasc Surg. 1966; 52: 322-330PubMed Google Scholar]. 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 [3Kim E.S. Putnam J.B. 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: 369-379Abstract Full Text Full Text PDF PubMed Scopus (242) Google Scholar, 4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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 [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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 [1Kattach 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: 323-324Abstract Full Text Full Text PDF PubMed Scopus (21) Google Scholar] 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 [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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 thymomas for many years [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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 [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar, 5Wilkins K.B. Sheikh E. Green R. et al.Clinical and pathologic predictors of survival in patients with thymoma.Ann Surg. 1999; 230: 562-574Crossref PubMed Scopus (158) Google Scholar]. 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 [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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. I read with interest the report by Dr Kattach and colleagues [1Kattach 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: 323-324Abstract Full Text Full Text PDF PubMed Scopus (21) Google Scholar] 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 [2Wilkins E.J. Edmunds L.H. Castleman B. Cases of thymoma at the Massachusetts General Hospital.J Thorac Cardiovasc Surg. 1966; 52: 322-330PubMed Google Scholar]. 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 [3Kim E.S. Putnam J.B. 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: 369-379Abstract Full Text Full Text PDF PubMed Scopus (242) Google Scholar, 4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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 [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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 [1Kattach 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: 323-324Abstract Full Text Full Text PDF PubMed Scopus (21) Google Scholar] 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 [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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 thymomas for many years [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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 [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar, 5Wilkins K.B. Sheikh E. Green R. et al.Clinical and pathologic predictors of survival in patients with thymoma.Ann Surg. 1999; 230: 562-574Crossref PubMed Scopus (158) Google Scholar]. 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 [4Detterbeck F.C. Parsons A.M. Thymic tumors.Ann Thorac Surg. 2004; 77: 1860-1869Abstract Full Text Full Text PDF PubMed Scopus (303) Google Scholar]. 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. ReplyThe Annals of Thoracic SurgeryVol. 81Issue 3PreviewWe 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]. Full-Text PDF

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