| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Ann Thorac Surg 1996;62:798-809
© 1996 The Society of Thoracic Surgeons
Thoracic Service, Departments of Surgery, Pathology, and Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York
 |
Abstract |
|---|
 TopFootnotes Abstract IntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
Methods. Primary lung tumors with neuroendocrine features operated on between 1984 and 1994 were reviewed and classified as typical carcinoid (TC), atypical carcinoid (AC), LCNC, MNC, and small cell lung cancer (SCLC) based on mitotic rate, extent of necrosis, and cytoarchitectural features. Immunohistochemistry was performed using antibodies MIB-1 for Ki67, pAb1801 for p53, OP-66 for Rb, 31G7 for EGFR. Staining was scored as 0 to 4+ (0 = less than 5%, 1+ = 5% to 20%, 2+ = 20% to 50%, 3+ = 50% to 80%, 4+ = more than 80%) for p53, Ki67, and EGFR; and negative, focal, or positive for Rb. Overall survival was calculated by the Kaplan-Meier method and prognostic factors compared by log rank test.
Results. Ninety-two tumors were examined: 25 TC, 7 AC, 24 LCNC, 18 MNC, 18 SCLC. The LCNC and MNC presented more frequently as stage II or III tumors (n = 28, 66%) than TC and AC (n = 5, 15%). Median survival for LCNC and MNC was 18.7 months, for SCLC 14.3 months, and has not been reached for TC and AC tumors. TC and AC tumors were uniformly characterized by low proliferative rate, absent p53, and normal Rb staining. LCNC, MNC, and SCLC showed a high proliferative rate, abnormal p53, and absent Rb staining. Overexpression of EGFR was frequent in all five tumor types.
Conclusions. (1) Ki67, p53, and Rb help distinguish LCNC and MNC from TC and AC. (2) Small numbers of patients preclude comparison of survival rates, but LCNC/MNC have a median survival similar to comparable early stage SCLC, and clearly worse than TC/AC. These results justify a sharp separation of high-grade neuroendocrine tumors from carcinoids, and suggest a close relationship between LCNC, MNC, and SCLC.
|
Introduction |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
N euroendocrine lung tumors exhibit a spectrum of histology and biological behavior ranging from well-differentiated, indolent typical carcinoid tumors, to histologically high-grade, biologically aggressive small cell lung cancers. In between these two well-defined extremes exists a broad group of less differentiated tumors that have been variably termed atypical carcinoids [1], well-differentiated neuroendocrine carcinomas [2, 3], or Kulchitzky cell carcinomas [4, 5]. Recently, the terms "large cell neuroendocrine carcinoma" and "mixed small cell-large cell neuroendocrine carcinoma" have been proposed to designate high-grade tumors intermediate between atypical carcinoids and small cell carcinoma.
Travis and colleagues [6] described large cell neuroendocrine carcinomas as tumors composed of large cells characterized by a light microscopic neuroendocrine appearance with a low nuclear to cytoplasmic ratio, frequent nucleoli, a high mitotic rate (greater than 10 mitoses per 10 high-power fields), and abundant necrosis. They did not find any advantage to electron microscopy, immunohistochemistry, or flow cytometry over light microscopy in classifying these tumors, which appeared to have a clinical prognosis intermediate between atypical carcinoids and small cell lung cancer. However, this newer grouping of typical and atypical carcinoids into low- and intermediate-grade neuroendocrine tumors, respectively, and of large cell neuroendocrine carcinomas and small cell lung cancers into high-grade neuroendocrine tumors is not widely accepted, partly because the number of patients originally reported by Travis and colleagues was small.
The entity of mixed small cell-large cell neuroendocrine carcinoma was proposed in 1982 for tumors consisting of small cell carcinoma with admixed large cells [7, 8]. This tumor appeared to have a poorer response to therapy than classic small cell lung cancer and was associated with a more aggressive course. The relationship of mixed small cell-large cell neuroendocrine carcinoma (MNC) to large cell neuroendocrine carcinoma (LCNC) has not been fully explored.
This study was performed to determine whether some of the molecular genetic abnormalities known to be important in both non-small cell and small cell lung cancers occur in these neuroendocrine lung tumors; and whether they can help characterize large cell and mixed small cell-large cell neuroendocrine carcinomas as distinct entities, and clarify their relationship to the other neuroendocrine lung tumors.
|
Material and Methods |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
. The histologic definitions used for TC and small cell lung cancers are well accepted (Figs 1 and 2), whereas those used for AC (Fig 3) represent a strict interpretation of the criteria originally proposed by Arrigoni and colleagues [1]. Large cell neuroendocrine carcinomas (Fig 4) were selected according to the criteria established by Travis and co-workers [6], and MNC (Fig 5) included high-grade tumors characterized by a mixture of large cell and small cell components, or a more homogeneous cell population having features intermediate between small and large cells [7, 8]. All consecutive cases of AC, LCNC, MNC, and SCLC were included as were 25 randomly selected TC from the same time period. Use of these strict histologic criteria resulted in reclassifying a significant number of tumors, particularly among the LCNC and MNC. As shown in Table 2, LCNC and MNC were previously given a variety of histologic diagnoses ranging from AC to small cell carcinoma, and were sometimes simply termed neuroendocrine carcinoma.
|
|
|
|
|
|
|
. Diaminobenzidine was used as the chromogen.
|
Stains for Ki67, p53, and EGFR (Figs 6, 7, and 8) were scored as 0 to 4+ based on the percentage of positive tumors cells (0 = less than 5%, 1+ = 5% to 10%, 2+ = 20% to 50%, 3+ = 50% to 80%, 4+ = more than 80%). Stains for Rb (Fig 9) were scored as positive (greater than 20% of tumor nuclei positive), focal (less than 20% of nuclei positive), or negative (no nuclei staining).
|
|
|
|
Statistical Methodology
Overall survival was calculated from the date of operation, and described using the product limit method of Kaplan and Meier [9]. Overall survival was compared across the levels of prognostic factors using the log rank test [10]. All statistical tests were conducted at the two-sided 0.05 level.
|
Results |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
. Twenty-five patients had TC, 7 had AC, 24 had LCNC, 18 had MNC, and 18 had SCLC. Because of the relatively small numbers of patients in each histologic category, analyses of clinical features, treatment, and outcome were performed by grouping together the TC and AC (low- and intermediate-grade tumors), and the LCNC with the MNC (both high-grade tumors). The median age was similar among these three categories and approximately half of the patients in each group were asymptomatic at the time of diagnosis, having had a pulmonary mass noted incidentally on chest radiograph. The remainder presented with cough, hemoptysis, shortness of breath, or postobstructive pneumonia. A few of the patients with either carcinoid tumors or LCNC or MNC received preoperative radiation or chemotherapy usually because SCLC was suspected on initial biopsy. However, two-thirds of the patients with SCLC did not receive any preoperative treatment emphasizing that these patients represent a highly select group with very early tumors, often diagnosed by resection of a peripheral pulmonary nodule. Not surprisingly, the largest proportion of nonsmokers belonged to the group of patients who had TC or AC, tumors known not to be tobacco related.
|
. In 4 patients the available clinical information was insufficient to encode the type of pulmonary resection in the data base. The most common form of resection in each tumor group was a lobectomy or bilobectomy consistent with the fact that most of tumors were stage I or II. However, 78% of carcinoid tumors and 50% of the SCLC were stage I, whereas only 31% of the LCNC and MNC were stage I. The largest number of stage III tumors (52%) belonged to the LCNC/MNC group.
|
. Only one of the AC patients was given postoperative radiation, whereas 38% of the LCNC and MNC patients and 50% of the SCLC patients received adjuvant radiation or chemotherapy. In the case of the LCNC and MNC patients the decision to offer adjuvant therapy was made on an individualized basis and appears to have been prompted by the locally advanced status or small cell-like histologic features of the tumor.
|
. There was a significant difference in overall survival for TC versus AC tumors (p = 0.02) and for AC versus LCNC (p < 0.01), but not for LCNC versus MNC tumors (p = 0.43), LCNC versus SCLC (p = 0.81), or MNC versus SCLC (p = 0.47). A comparison of the low/intermediate-grade tumors (TC and AC) to the high-grade tumors (LCNC, MNC, and SCLC) shows that the difference in overall survival rates (Fig 11) is highly significant (p < 0.01). In a multivariate analysis controlling for stage, histology had a significant effect on survival when comparing SCLC to TC and AC tumor (p < 0.01). The difference in survival between SCLC and LCNC and MNC tumors again did not reach statistical significance (p = 0.06).
|
|
. Only one of the AC and none of the TC showed 3 to 4(+) staining for Ki67. The remainder exhibited a low proliferative rate. Approximately one-third of the TC and AC group overexpressed the EGFR but abnormal p53 expression and absence of Rb expression were uniformly not seen. In contrast, almost all LCNC, MNC, and SCLC exhibited a high proliferative rate as assessed by 3 to 4(+) staining for Ki67. Both the LCNC and MNC and the SCLC tumors frequently overexpressed the EGFR although this occurred more often among the LCNC and MNC tumors (42% and 39%, respectively, versus 22% for the SCLC). These differences were not statistically significant (p = 0.19). Abnormal p53 expression was seen more commonly in the MNC and SCLC (each 39%) than in the LCNC (17%, p = 0.11). Absent Rb expression was found in 14 (58%) of the LCNC, 16 (89%) of the MNC tumors, and 17 (94%) of the SCLC. The differences in Rb expression were statistically significant for LCNC tumors versus SCLC (p = 0.01), but not for MNC versus SCLC (p = 0.51).
|
|
Comment |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
The study by Arrigoni and colleagues established AC as a distinct histopathologic entity [11] and helped identify all carcinoid tumors as low-grade malignancies rather than benign tracheobronchial tumors [12]. It is now clear that neuroendocrine lung tumors form a disease spectrum ranging from bland-appearing indolent typical carcinoids to biologically aggressive SCLC [13–17]. However, the broad range of tumors in between these two extremes have defied easy, reproducible classification [18]. Frequently all higher grade tumors not showing the characteristics of SCLC have been loosely termed AC, thereby considerably extending Arrigoni's original specific histologic criteria. Alternative classification schemas, notably that by Gould and Warren, propose that these tumors should be termed well-differentiated neuroendocrine carcinomas and divided into three subsets based on pleomorphism, mitotic count, and necrosis [2, 3, 19]. Another classification schema suggested calling TC and AC, Kulchitzky cell carcinomas types I and II, and SCLC, Kulchitzky cell carcinoma type III, in deference to the common cell of origin of these neuroendocrine tumors [4, 5]. Neither of these classification schemas have been widely accepted, perhaps because they do not lend themselves easily to clinical application. However, the simple grouping of neuroendocrine lung tumors into TC and AC and SCLC also remains inadequate to describe the broad range of histologic appearance and biological behavior of these tumors [20].
Recently, Travis and colleagues [6] proposed the term of LCNC to describe tumors that are high grade but lack the cytologic features of SCLC. These tumors are characterized by (1) a light microscopic neuroendocrine appearance, (2) cells of large size with low nuclear-to-cytoplasmic ratio and frequent nucleoli, and (3) high mitotic rate (greater than 10 mitoses per 10 high-power field) and frequent necrosis. Large cell neuroendocrine carcinomas are considered distinct from NSCLC with neuroendocrine features in which neuroendocrine differentiation is detectable only by immunohistochemistry or electron microscopy. The latter group of tumors fall under the standard classification of NSCLC and there is currently no evidence that the neuroendocrine features of these tumors indicate a different biological behavior [21]. Although the classification by Travis and co-workers neatly describes the histologic spectrum of neuroendocrine lung tumors, their original analysis was based on only five LCNC and has not yet gained wide acceptance. Thus, previous classification schemas for neuroendocrine lung tumors are not widely used, and a more recently proposed schema appears practical but needs further validation.
The entity of MNC was formally separated as a subtype of SCLC by the International Association for the Study of Lung Cancer in 1988, when it was also recognized that the "intermediate cell" subtype of SCLC represented a category without clinical significance [7]. The MNC contained both small cells with the typical cytoarchitectural features of SCLC as well as larger cells with nucleoli and more abundant cytoplasm. Several studies have shown a more aggressive clinical course and a reduced response to chemotherapy for MNC, relative to SCLC [8, 22, 23]. Unfortunately, recent reclassifications of pulmonary neuroendocrine tumors have not specifically explored the relationship of MNC to LCNC [6].
Immunohistochemistry for standard neuroendocrine markers (eg, neuron-specific enolase, chromogranin, synaptophysin), electron microscopy and flow cytometry have been used to determine whether they might augment the histologic classification of neuroendocrine lung tumors and assist in separating low-grade from high-grade tumors. Unfortunately, none of these methods appear clinically useful because staining for neuroendocrine markers among these tumors is highly variable, and abnormal DNA content is frequent among both TC and AC [24, 25].
Although the cases included in this study did not result from a systematic review of all lung tumors, it is apparent that the number of AC is much less than might be expected from the reported frequency of this tumor relative to TC. This most likely resulted from the use of very strict criteria for classification, with the resultant inclusion of some cases in the high-grade groups that might have been regarded as AC with more liberal criteria.
We hypothesized that if LCNC and MNC belong to the group of higher grade tumors within the neuroendocrine spectrum, closely related to SCLC, they should exhibit molecular genetic abnormalities that are common in SCLC. Although the precise mechanisms that lead to the development of NSCLC and SCLC are not known, several common molecular genetic abnormalities have been identified in those tumors. Both NSCLC and SCLC seem to arise as a result of combined inactivation of tumor suppressor genes and activation of oncogenes. Frequently inactivated tumor suppressor genes include p53 and Rb along with a putative tumor suppressor gene located on chromosome 3p [26, 27]. Frequently activated oncogenes include K-ras [28] and the EGFR, which is thought to participate in an autocrine growth loop with one of its ligands, transforming growth factor alpha. Although K-ras activation by point mutation is almost always confined to adenocarcinomas, altered expression of p53, Rb, and EGFR is seen across NSCLC histologies and stages, and can be reliably detected by immunohistochemistry. Although Rb abnormalities may be seen in 30% of NSCLC, they are nearly universal in SCLC, perhaps representing a relative molecular distinction between endocrine and nonendocrine lung cancers [29]. The expression of EGFR is normally confined to the basal layer of the bronchial epithelium and overexpression can be detected in the earliest preneoplastic lesions, even in areas of bronchial atypia and low-grade dysplasia [30]. Overexpression of EGFR is infrequent in SCLC, but is seen in approximately half of all NSCLC [31]. The p53 immunohistochemical staining caused either by mutations of the p53 gene or inactivation of the normal protein product, is seen in approximately half of NSCLC and SCLC, and also occurs in areas of high-grade bronchial dysplasia and carcinoma-in-situ [30, 32]. Thus, EGFR and p53 overexpression and loss of Rb expression constitute frequent molecular genetic abnormalities that can be easily detected by immunohistochemical staining performed on archival lung tumor samples.
Less is known about the molecular genetic abnormalities associated with carcinoid tumors [33]. Roncalli and colleagues [34] compared the p53 immunohistochemical staining in 15 TC, 22 AC, and 22 SCLC. None of the TC showed positive staining, whereas 45% of the AC and 59% of the SCLC showed immunoreactivity. However, the AC were classified according to the criteria of Gould and Warren for well-differentiated neuroendocrine carcinoma and therefore it is possible that their group of "atypical" carcinoids included tumors that might fit Travis' criteria for LCNC. Barbareschi and colleagues [35] examined the expression of p53 and Rb in 14 TC, 10 AC, 4 "borderline atypical carcinoids/SCLC," and 11 SCLC [35]. They found that p53 expression was absent in all carcinoids, abnormally expressed in 8 SCLC and in 1 "borderline" case. Rb expression was present in TC and AC and absent in all other tumors. Although the criteria for distinguishing AC and borderline cases were not clearly stated, this study suggested that it might be possible to use immunohistochemical staining for several common molecular genetic abnormalities to help distinguish among groups of neuroendocrine tumors.
Our study confirms and extends Barbareschi's report. Ki67, considered a very reliable marker of proliferative rate, indicated that all but 2 LCNC and MNC categorized by light microscopic criteria were highly proliferative tumors. p53 immunoreactivity occurred in none of the TC or AC, but was seen in 17% of LCNC, 39% of MNC tumors, and 39% of SCLC. Absence of Rb expression was found in 94% of SCLC, 89% of MNC, and 58% of LCNC. EGFR overexpression was common to all neuroendocrine tumor types, occurring in 39% of carcinoids, 42% of LCNC, 39% of MNC, and 22% of SCLC. These results allow a sharp separation of low/intermediate-grade from high-grade tumors and suggest that LCNC, MNC, and SCLC share common molecular genetic features. The relatively high frequency of Rb abnormalities is consistent with the hypothesis that high-grade neuroendocrine carcinomas share this frequent molecular abnormality and that SCLC is closely related to MNC (especially) and LCNC.
The confusion about the histologic classification of neuroendocrine lung tumors creates a significant dilemma for clinicians treating these neoplasms. Surgical resection is the accepted treatment for TC and AC, whereas locally advanced NSCLC are now managed with combined modality therapy, and the small group of very early SCLC included in this series are most frequently treated by resection and postoperative adjuvant chemotherapy. Discrepancies in pathologic diagnoses between small initial biopsy specimens and subsequent larger surgical resection specimens related to tumor heterogeneity or to variable use of classification schemas makes it even harder for clinicians to develop appropriate and effective treatment plans. Within the limitations of this retrospective study the poor clinical outcome of patients with LCNC and MNC raises the issue of whether they should be considered for formal trials of combined modality therapy. Approximately half of these patients presented with locally advanced tumors (T3-4, or N2-3) and median survival was only 18.7 months, despite 40% of patients having received postoperative adjuvant radiation or chemotherapy. Moreover, distant metastases developed in 66% of the patients who relapsed. This contrasts sharply with TC and AC, as surgical resection offers a significant chance of cure even when nodal metastases are present [36].
Thus, the current study suggests that it may now be possible to define specific groups of low/intermediate-grade and high-grade neuroendocrine tumors based on the combined use of light microscopic criteria, proliferative rate, and at least two molecular markers. The SCLC, MNC, and LCNC appear to represent a spectrum of related high-grade neuroendocrine neoplasms sharing molecular features as well as aggressive biological behavior. The poor overall survival and frequency of distant metastases suggest that patients with LCNC and MNC should be targeted for formal investigation of other approaches to treatment, specifically combined modality therapy.
|
Acknowledgments |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
|
Footnotes |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
Address reprint requests to Dr Rusch, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY 10021.
|
References |
|---|
|
TopFootnotesAbstractIntroductionMaterial and MethodsResultsCommentAcknowledgmentsReferences |
|---|
Related Article
This article has been cited by other articles:
|
|
 |
|
  O. B. Rickman, P. K. Vohra, B. Sanyal, J. A. Vrana, M.-C. Aubry, D. A. Wigle, and C. F. Thomas Jr. Analysis of ErbB Receptors in Pulmonary Carcinoid Tumors Clin. Cancer Res., May 15, 2009; 15(10): 3315 - 3324. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. A. Moran, S. Suster, D. Coppola, and M. R. Wick Neuroendocrine Carcinomas of the Lung: A Critical Analysis Am J Clin Pathol, February 1, 2009; 131(2): 206 - 221. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Rugge, M. Fassan, R. Clemente, G. Rizzardi, L. Giacomelli, G. Pennelli, C. Mescoli, D. Segat, and F. Rea Bronchopulmonary Carcinoid: Phenotype and Long-term Outcome in a Single-Institution Series of Italian Patients Clin. Cancer Res., January 1, 2008; 14(1): 149 - 154. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Iyoda, K. Hiroshima, Y. Nakatani, and T. Fujisawa Pulmonary Large Cell Neuroendocrine Carcinoma: Its Place in the Spectrum of Pulmonary Carcinoma Ann. Thorac. Surg., August 1, 2007; 84(2): 702 - 707. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Fujiwara, I. Sekine, K. Tsuta, Y. Ohe, H. Kunitoh, N. Yamamoto, H. Nokihara, K. Yamada, and T. Tamura Effect of Platinum Combined with Irinotecan or Paclitaxel against Large Cell Neuroendocrine Carcinoma of the Lung Jpn. J. Clin. Oncol., July 24, 2007; (2007) hym053v1. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Rossi, A. Cavazza, A. Marchioni, L. Longo, M. Migaldi, G. Sartori, N. Bigiani, L. Schirosi, C. Casali, U. Morandi, et al. Role of Chemotherapy and the Receptor Tyrosine Kinases KIT, PDGFR{alpha}, PDGFR{beta}, and Met in Large-Cell Neuroendocrine Carcinoma of the Lung J. Clin. Oncol., December 1, 2005; 23(34): 8774 - 8785. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. J. Battafarano, F. G. Fernandez, J. Ritter, B. F. Meyers, T. J. Guthrie, J. D. Cooper, and G. A. Patterson Large cell neuroendocrine carcinoma: An aggressive form of non-small cell lung cancer J. Thorac. Cardiovasc. Surg., July 1, 2005; 130(1): 166 - 172. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Iyoda, K. Hiroshima, Y. Moriya, T. Mizobuchi, M. Otsuji, Y. Sekine, K. Shibuya, T. Iizasa, Y. Saitoh, and T. Fujisawa Pulmonary large cell neuroendocrine carcinoma demonstrates high proliferative activity Ann. Thorac. Surg., June 1, 2004; 77(6): 1891 - 1895. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Paci, A. Cavazza, V. Annessi, I. Putrino, G. Ferrari, S. De Franco, and G. Sgarbi Large cell neuroendocrine carcinoma of the lung: a 10-year clinicopathologic retrospective study Ann. Thorac. Surg., April 1, 2004; 77(4): 1163 - 1167. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Zacharias, A. G. Nicholson, G. P. Ladas, and P. Goldstraw Large cell neuroendocrine carcinoma and large cell carcinomas with neuroendocrine morphology of the lung: prognosis after complete resection and systematic nodal dissection Ann. Thorac. Surg., February 1, 2003; 75(2): 348 - 352. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Iyoda, K. Hiroshima, M. Baba, Y. Saitoh, H. Ohwada, and T. Fujisawa Pulmonary large cell carcinomas with neuroendocrine features are high-grade neuroendocrine tumors Ann. Thorac. Surg., April 1, 2002; 73(4): 1049 - 1054. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. Lonardo, V. Rusch, J. Langenfeld, E. Dmitrovsky, and D. S. Klimstra Overexpression of Cyclins D1 and E Is Frequent in Bronchial Preneoplasia and Precedes Squamous Cell Carcinoma Development Cancer Res., May 1, 1999; 59(10): 2470 - 2476. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
