An evaluation of mediastinoscopy in the management of presumably operable bronchial carcinoma

The Lymphatic Spread of Lung Cancer: An Investigation of the Anatomy of the Lymphatic Drainage of the Lungs and Preoperative Mediastinal Staging

The knowledge of lymphatic spread of lung cancer permitted the study of anatomy of lymphatic drainage of the lungs. The history of anatomy of lymphatic drainage of the lungs began in the 15th century. In the human, pulmonary lymph flows to the lymph nodes around the lobar bronchi and thence to extrapulmonary lymph nodes located around the main bronchi and trachea and its bifurcation (tracheobronchial lymph nodes). These send their efferents to a right and left mediastinal lymph trunks, which may join the thoracic duct, but usually drain opening directly into the brachiocephalic vein of their own side.

Assessment of Operability and Resectability in Lung Cancer

Lung cancer is a lethal disease, and chronic cigarette smoking is the most common cause. The selection of treatment is based on the histologic cell type, accurate staging, and adequacy of cardiopulmonary functional reserve. The risk for surgery is highest in patients over the age of 80 years.

Can Biologic Aggressiveness and Metastatic Potential of Primary Lung Cancer Be Predicted from Clinical Staging Alone?

The future biologic aggressiveness and metastatic potential of lung cancer, as in other cancers, cannot be predetermined from the current clinical information, imaging studies, and pathologic examination whose purpose is to provide diagnosis and mutation studies and molecular drivers only in making decision for treatment. There is a need for better understanding of the biologic characteristics and aggressiveness of lung cancer. The most that is achieved from clinical staging and pathologic staging is in the planning of treatment of lung cancer and predicting prognosis. Aggressive biologic behavior to come is not within the domain of clinical staging or pathologic staging.

Current status of mediastinal lymph node dissection versus sampling in non-small cell lung cancer

This article addresses the appropriate use of lymph node sampling versus dissection, recommendations for minimum sampling for staging, and the role of lymph node dissection in improving survival.

Safety of Mediastinoscopy in Anatomical Variations of the Mediastinum: The Situs Inversus Syndrome

Mediastinoscopy has been widely used by thoracic surgeons to evaluate the superior mediastinum since 1959. Large series of mediastinoscopy have been reported with very low morbidity and no mortality. Proper attention to surgical techniques and mediastinal anatomy are essential to maintain the safety of the procedure. Situs inversus totalis is exceedingly rare, but variations in mediastinal anatomy in this group of patients can render the procedure challenging for the thoracic surgeon. A case of mediastinoscopy in a situs inversus patient is presented with emphasis on anatomical variations of the mediastinum and technical pitfalls of the procedure in this rare group.

Mediastinal Staging 2005: Pictures, Scopes, and Scalpels

Staging of the mediastinum for lung cancer has matured dramatically with the advent of newer technologies in imaging and endoscopic surveillance. Some of these technologies such as positron emission tomography (PET) scanning are becoming mainstream in the evaluation of patients with clinically suspicious mediastinal disease as seen on computed tomography (CT), while others such as endobronchial ultrasound are reserved for specialty expertise and await validation. While much improvement has been made in the accurate preoperative staging of patients having surgery as the primary modality in lung cancer, controversy exists regarding the restaging of locally advanced cases after induction chemotherapy or chemoradiotherapy. A major concentration on these restaging issues is warranted since it is now generally agreed that sterilization of the mediastinum after induction therapy has an impact on the prognosis of patients with stage IIIA disease, and accurate staging after therapy may rationally guide diverse therapeutic interventions in these patients.

Surgical exploration of the mediastinum: mediastinoscopy and intraoperative staging

Lung resection remains the therapy of choice offering the greatest potential for cure in non-spread lung cancer. Prognostic importance of lymph-node involvement has been underlined by several studies. So, exploration of the mediastinum is of major importance for defining the therapeutic strategy in a possibly curative setting. Pre-resectional exploration of the mediastinal lymph-nodal status is mandatory to define tumour stage exactly and establish specific therapy. Cervical mediastinoscopy is the primary diagnostic procedure and remains the gold standard in invasive surgical staging. Complementary, parasternal mediastinoscopy, extended mediastinoscopy, and video-assisted thoracoscopy may be performed. These techniques allow accurate assessment of mediastinal lymph-node involvement, resulting in an appropriate judgement as to resectability and possible treatment options. Different techniques are established for intraoperative exploration and staging. In terms of curative surgery of lung cancer we demand accurate staging which is achieved by systematic and complete Lymph-node dissection. So, individually and dependent on primary tumour site, accurate mediastinal staging of Lung cancer should be performed in combination with definitive lung resection.

Prognostic significance of persistent mediastinal metastasis following induction therapy in large (> or = 2 cm) N2 or N3 non-small cell lung cancer

OBJECTIVE

It is controversial whether or not surgery is beneficial for patients with non-small cell lung cancer accompanied by persistent lymph node metastasis in the mediastinum following induction therapy. We have therefore conducted a retrospective study to assess this issue.

METHODS

Eligibility criteria were defined as follows: 1) the period of treatment was between January 1991 and April 1998, 2) the clinical stages were IIIA (N2) or IIB (N3) with large lymph nodes (> or = 2 cm), 3) induction therapy had been administered, 4) tumor was resected completely, 5) at least one mediastinal lymph node had necrosis or scar if the pathological N status was p-N0 or p-N1 and 6) the p-stage was not IV. Dichotomous variables included the radiographic response of the tumor, the T status, and the N status.

RESULTS

Thirty-nine patients were eligible. There were 29 males and 10 females aged from 27 to 74 years, and involved 20 cases of adenocarcinoma. The pathological N status was as follows: p-N0 in 18 patients, p-N1 in 3, p-N2 in 16, and p-N3 in the other 2. In overall survival, the median survival time (MST) was 34 months and the actuarial 5-year-survival rate (5-YSR) was 28%. The group of patients with either N0 or N1 (n = 21) had a 71-month MST and a 54% 5-YSR, and the group of patients with either N2 or N3 (n = 18) had a 13-month MST and a 5-YSR of 0% (p < 0.0001). On multivariate analysis, the pathological N factor was confirmed as an independently significant.

CONCLUSIONS

Our retrospective study found that the survival rate of patients with persistent mediastinal nodal metastasis was very poor. A prospective study is needed to investigate whether or not surgery is beneficial for these patients.

Duration of knowledge in general thoracic surgery

BACKGROUND

Medical knowledge changes rapidly, so current medical education approaches emphasize the development of life-long learning skills ("teaching the learner to learn") as opposed to the simple acquisition of contemporary medical knowledge. Because there are no data on the rapidity of change of general thoracic surgical knowledge, we do not know whether this trend in medical education is appropriate for thoracic surgical trainees. We undertook a study to assess the duration of knowledge in general thoracic surgery.

METHODS

The first general thoracic surgery article from each issue of The Annals of Thoracic Surgery between 1965 and 1997 was abstracted into a summary statement. A form, made up of 360 summary statements in random order, was assessed by 6 general thoracic surgeons. They assessed statement validity on a 5-point scale (1 = statement false; 5 = statement true). Average statement validity scores for 30 time intervals were calculated. The relationship between time of publication and statement validity was analyzed.

RESULTS

Average validity scores ranged from 2.24 (represents 1965 to 1966) to 4.32 (represents 1969 to 1970). Validity scores increased with time (y = 3.46 + 0.017x, where y is validity score and x is time), and this was significant (r = 0.40; p = 0.027). However, the absolute change in average validity scores over the 33-year study period was only 0.52 or 13.1% of the "modern" era scores.

CONCLUSIONS

The assumption that medical knowledge changes quickly may not be true in general thoracic surgery. Although life-long learning skills are important, general thoracic surgery training programs should continue to emphasize fundamental knowledge in the specialty.

Video-assisted thoracic surgery for diseases within the mediastinum

VATS and concepts of minimal access thoracic surgery have revitalized many aspects of general thoracic surgery, including the surgical approach to diseases and conditions of the mediastinum. Proven surgical options that have been shunned by patients and referring physicians because of the perceived morbidity of thoracotomy have been reconsidered with the emergence of these minimal access surgical options. Continued critical review of the accumulating experience in VATS techniques will refine the surgical indications for VATS and open thoracotomy.

Mediastinoscopic treatment of mediastinal cysts

Selected patients with mediastinal cysts can be managed safely and effectively by mediastinoscopic techniques. Small cysts in favorable locations can be excised partially or nearly completely. Cysts that are intimately associated with vital structures are better suited to mediastinoscopic cystotomy and chemical sclerosis. Three cases are presented and technical aspects are discussed.

Tension Pneumothorax: Etiology, Diagnosis, Pathophysiology, and Management

The normally air-free pleural cavity exists at subatmospheric pressure to promote pleural apposition and proper lung excursion. Owing to its unique bilayer structure, air introduced into this space either from within the thoracic cavity or from an extrathoracic source causes pleural separation and simple pneumothorax (PTX). Most simple pneumothoracies of a small or static volume in healthy patients do not appreciably impair cardiopulmonary function despite variable collapse of the lung. If increasing pressure develops within this pleural air collection, however, a cascade of pathophysiological changes can result from altered anatomical positions of heart, lung, and great vessels. The development of increasing pressure within the pleural space, with resultant ipsilateral lung collapse and hemithoracic expansion into the mediastinum and the contralateral lung, is termed tension pneumothorax (TPTX). The exact incidence of TPTX is unknown, but it is reported in up to 2 to 3% of all pneumothoracies. Certain medical and surgical disease states—many found within the critical care environment—place patients at higher risk for development of TPTX and also limit physiological tolerance to TPTX once it occurs. Although physical examination and chest radiography generally confirm the occurrence of TPTX, physiological monitoring may herald the development of increasing intrapleural pressure. Expeditious recognition and pleural decompression are necessary to prevent the untoward hemodynamic and respiratory consequences of TPTX. Significant morbidity and mortality may arise from TPTX if treatment is unduly delayed, particularly in mechanically ventilated patients.

The prognostic significance of preoperative assessment of mediastinal lymph nodes in patients with lung cancer

In order to evaluate the prognostic significance of the preoperative assessment of mediastinal lymph nodes, 100 patients with potentially operable lung cancer underwent two-plane tomography, computed tomography (CT), transbronchial needle aspiration (TBNA; 47 patients), and cervical mediastinoscopy. Mediastinoscopy proved to be the most accurate staging procedure. Tomography was less specific, detecting only advanced mediastinal node involvement, and CT was as sensitive as mediastinoscopy but sensibly less specific. TBNA gave no false positive results but a false negative rate of 25.5 percent. Accurate preoperative staging of mediastinal nodes is mandatory to optimize the resectability rate of lung cancer. Where metastatic involvement of mediastinal nodes was preoperatively documented at more than one level, tumors were invariably unresectable. Mediastinoscopic demonstration of intracapsular metastases at only one level did not preclude complete resection. Before thoracotomy, confirmation of neoplastic spread to mediastinal nodes suggests very low survival rates, especially in patients with incomplete removal of tumors.

Mediastinal assessment for staging and treatment of carcinoma of the lung

Invasive diagnostic procedures for mediastinal assessment, such as mediastinoscopy, are necessitated by the importance of staging lung cancers, both to plan the treatment and to estimate the prognosis. Other noninvasive techniques may complement or be substituted for mediastinoscopy under certain specific clinical settings. Thus with the introduction of newer diagnostic technologies, such as computed axial tomography, the strategy for mediastinal assessment should be continually reevaluated. In this review, the diagnostic sensitivity, specificity, and overall accuracy of various techniques reported in the literature are examined to elucidate their current roles in assessing the mediastinal involvement in patients with lung cancer.

The role of gallium-67 in the clinical evaluation of cancer

This review is based primarily on historic data, and it examines the indications for and limitations of gallium-67 scanning in the evaluation of patients with neoplasms. The use of gallium-67 scans is discussed according to tumor type, and data from the most representative and comprehensive studies are included. The results described, some of which were obtained primarily with older imaging techniques, should be regarded as representing the minimum that can be expected from application of this imaging procedure.

Pre-operative mediastinal evaluation in primary bronchial carcinoma--a review of staging investigations

A review of staging investigations in the preoperative evaluation of mediastinal involvement in primary bronchial carcinoma is presented. The following conclusions are offered as guidelines for the use of mediastinal staging procedures in clinical practice: Surgical staging methods have the over-riding advantage of superior specificity over indirect imaging techniques. Where 67Ga-imaging or CT scanning are not available, routine pre-operative mediastinoscopy or, when appropriate, mediastinotomy will identify most patients with non-resectable disease but this approach entails a high proportion of true negative examinations. Radioisotope ventilation and perfusion lung imaging has no place in the pre-operative staging of lung cancer. Where the techniques are available, 67Ga-imaging and CT scanning have a use in selecting patients for mediastinal exploration. A negative mediastinal 67Ga scan or a negative CT examination suggest that mediastinal exploration will be unrewarding in the vast majority of cases and may be omitted prior to thoracotomy. A positive mediastinal 67Ga scan or the demonstration of abnormal mediastinal nodes by CT is an indication for mediastinal exploration which, if negative should be followed by thoracotomy.

Flexible transbronchial needle aspiration for staging of bronchogenic carcinoma

Flexible transbronchial needle aspiration (TBNA) provides access to mediastinal lymph nodes, but its role in staging bronchogenic carcinoma is unknown. To determine the efficacy and safety of this procedure for staging the extent of mediastinal disease, the results of TBNA performed during fiberoptic bronchoscopy in 39 patients without known extrathoracic metastases were reviewed. Flexible TBNA was found to be a safe, effective method for determining the presence or absence of mediastinal metastases from bronchogenic carcinoma. Furthermore, TBNA results compare favorably with roentgenographic staging techniques, with the added advantage of providing cytopathologic information.

Preoperative staging of lung cancer: accuracy of computed tomography versus mediastinoscopy

Forty-four patients coming to surgery for carcinoma of the bronchus underwent preoperative staging of the mediastinum by computed tomography (CT scanning) and surgical exploration of the mediastinum by cervical mediastinoscopy or left anterior mediastinotomy or both. Where mediastinal nodes were affected the sensitivity and specificity of computed tomography was inferior to that of mediastinoscopy (57% and 85% versus 71% and 100%). The sensitivity of computed tomography in predicting mediastinal invasion was superior to that of mediastinoscopy (77% v 46%), especially in the case of lower-lobe tumours (67% v 17%). Mediastinoscopy had the considerable advantage of 100% specificity. In the assessment of hilar lymphadenopathy computed tomography had a sensitivity of 38% and a specificity of 64%. In cases where computed tomography showed a normal mediastinum or enlargement of the hilar glands only, mediastinal exploration conferred no additional information and could have been omitted. A computed tomography scan showing mediastinal abnormality is an indication for mediastinoscopy and not a contraindication to surgery. In 23 patients computed tomography showed some abnormality of the mediastinum, confirmed at mediastinoscopy in 12 cases. The remaining 11 patients underwent thoracotomy, resection being carried out in nine. Postsurgical staging showed that six of these tumours were N0 lesions without invasion; in two further N0 cases there was a minor degree of mediastinal invasion which did not prevent resection, and the remaining tumour was N1 without invasion.

When and how to invade for the diagnosis and staging of primary lung cancer

In search of perspectives pertaining to the selection of invasive procedures for evaluating patients with lung cancer, data from other centers were considered, and our recent consecutive experience with 40 lung cancer patients was reviewed. Cost estimates for the least and the most complete use of invasive procedures were done. An average of three procedures per patient was used. Information judged beneficial was obtained from 94 for 120 procedures (78 percent). By retrospective analysis, 15 procedures (0.38 per patient) provided no useful information. An approach to the use of invasive procedures in the management of patients with suspected lung cancer is proposed.

Transbronchial fine needle aspiration

In a pilot study, 21 patients underwent transbronchial fine needle aspiration (TBFNA) using a 45 cm-22 gauge needle guided by means of a semi-rigid metal sleeve, which was introduced through a standard rigid bronchoscope. A total of 33 aspirations were performed from main carina (15), paratracheal (five), and lobar carinal (13) foci. Six aspirations yielded malignant cellular samples, 22 aspirations presented only normal cells, and in five no adequate cellular sample was obtained. Fifteen patients underwent surgical exploration (mediastinoscopy with or without thoracotomy). Four of the cytologically malignant cases were explored and in three the aspiration site was confirmed histologically. In the remaining patients where the site of aspiration was explored, no tumour was demonstrated in the cytologically negative or cytologically inadequate cases. There were no complications from TBFNA. We suggest that TBFNA is useful in determining mediastinal malignant involvement rapidly and with lesser invasion than with current techniques.

Selection by mediastinoscopy and long-term survival in bronchial carcinoma

In order to reduce the high rate of inoperability in patients with bronchial carcinoma, mediastinoscopy was carried out as a routine preoperative selection in 874 patients during 13 years. Two hundred thirty-six patients (27%) were found to have involved lymph nodes at mediastinoscopy and were not treated surgically. Follow-up data were available on 210 of them: 165 (79%) died within a year, 16 survived for 2 years, and 4 for 5 years. Pulmonary resection was carried out in 638 patients. Five-year survival in the series was 24.5% and 10-year survival (based on 104 eligible patients), 16.3%, including the operative mortality of 5.5%. Mediastinoscopy has not improved long-term survival to any great extent. However, it has raised the rate of resectability to 97.1% and lowered the operative mortality without denying the patient a chance of cure.

The importance of mediastinal lymph node invasion by pulmonary carcinoma in selection of patients for resection

Resection results from 417 consecutive patients operated on between January 1, 1964, and December 30, 1969, were analyzed in March, 1976. This period was chosen to allow a five-year follow-up. The results of resection in 56 patients with invaded mediastinal nodes are reported. Mediastinoscopy to assess resectability was not used for any of the 417 patients. Our low incidence of mediastinal node invasion (56 out of 417, or 13.4%), a resectability rate of 97.4%, and a hospital mortality of 2.8% for resection of advanced carcinoma suggest that routine mediastinoscopy prior to resection is not necessary. Traditional methods of preoperative assessment and the use, when indicated, of extended resection for patients with mediastinal node invasion result in worthwhile salvage of patients with invaded mediastinal nodes.

Mediastinoscopy

A series of 150 mediastinoscopic examinations, performed at The Prince Charles Hospital, Brisbane, is reported. The procedure was employed as a diagnostic aid in the care of patients known to be suffering from disease processes involving the superior mediastinum, and as a preoperative assessment in a group of patients known to have, or suspected of having, bronchogenic carcinoma, There was no mortality. The morbidity rate was 2%.

Mediastinoscopy and bronchial carcinoma: experience with 600 mediastinoscopies

Of 600 mediastinoscopies carried out from 1966 to 1973, 479 were performed to assess the operability of a pulmonary carcinoma. Of these, 206 (43%) were positive and 273 (57%) were negative. Of the 161 patients found positive during an initial period, 147 were refused operation; the remaining 14 were considered suitable candidates for operation, either because only one homolateral lymph node site was involved or because there was a concomitant osteoarthropathy. The tumour was irresectable in one of these 14 patients who died after 3-5 months; curative resection was possible in one and palliative resection in 12 patients. These 12 patients all died within a year. Of the 184 patients found negative during an initial period, 149 were treated by operation. The tumour proved irresectable in seven (5%), while curative resection was possible in 113 (76%) and palliative resection in 29 (19%) patients. Comparison with the period 1957-63, when in the same hospital resection was performed after a negative Daniels' (scalene node) biopsy, shows that the tumour was irresectable in 25 (20%) of the 124 patients with a negative biopsy, while curative resection was possible in 43 (35%) and palliative resection in 56 (45%) patients. During a second period, patients with a positive mediastinoscopy were in principle refused operation. Of 89 negative patients, 81 were treated by operation. No tumour was found to be irresectable; curative resection was possible in 63 (78%) and palliative resection in 18 (22%) patients. An operation for bronchial carcinoma was performed on 167 patients between September 1970 and September 1973 after a negative mediastinoscopy in 95, and without mediastinoscopy in 71 patients, either because of a peripheral tumour (70) or because of a tumour relapse after two years (1). The resection was palliative in 11% of the 71 cases, but in only one patient with a peripheral tumour could a mediastinoscopy have been positive. Finally, an operation was performed on one patient with a positive mediastinoscopy and a tumour relapse after six years. A survival study was made of the first 100 patients with pulmonary carcinoma, operated on between September 1970 and March 1972 and with a follow-up from a minumum of two years to a maximum of 3-5 years. The early mortality averaged 10% and was higher after pneumonectomy than after lobectomy. The late mortality was 16% after curative lobectomy, 38% after curative pneumonectomy, and 83% after palliative pneumonectomy. The survival after 2 to 3-5 years was 63%.

Mediastinoscopy. An analysis of 320 consecutive cases

Three hundred and twenty consecutive cases of mediastinoscopy are analysed. Mediastinoscopy is a safe procedure and causes little disturbance to the patient.The preoperative assessment of patients with presumably resectable bronchial carcinoma was the main indication for mediastinoscopy, and its use was associated with a fall in the non-resectability rate at thoracotomy from 28 to 15 per cent over two 3-year periods.The policy of exclusion from exploratory thoracotomy of patients with bronchial carcinoma and mediastinal lymph-node metastases is discussed in relation to the histological nature of the lesion and the site and extent of the mediastinal node involvement.It is concluded that there is a case for offering resection to selected patients with limited mediastinal node invasion from bronchial carcinoma.The value of mediastinoscopy as a diagnostic procedure for mediastinal and pulmonary hilar masses and for undiagnosed pulmonary opacities is shown.