Mediastinoscopic ultrasonography (MUS)

Correct pre-therapeutic T4 staging is mandatory for neo-adjuvant studies and for the decision on surgical therapy of high-risk patients. T4-staging of centrally located lung-cancer by means of non-invasive imaging techniques is either of low accuracy (CT and NMR) or important regions are not accessible due to air interference with the tracheo-bronchial tree (trans-esophageal-endosonography, TEE). We here describe for the first time the new technique of mediastinoscopic ultrasonography (MUS). A fingertip ultrasound probe is introduced through the video-mediastinoscope. The probe lies in front of the tracheo-bronchial tree and in direct contact with the vena cava and pulmonary artery. This position allows examining those regions that are not accessible with TEE. In a pilot study with 12 patients, visualization of central vessels and their relation to the tumor was excellent and without artifacts. In 3 patients, MUS did not confirm the T4 stage predicted by CT Scan. Those three patients underwent successful pneumonectomy (R0-resection) while the other nine patients received induction treatment. MUS is a promising addition to CT scanning, NMR, and transesophageal ultrasound in staging of centrally located tumors.

[18F-fluorodeoxyglucose positron emission tomography in the diagnosis of lung cancer]

Positron emission tomography (PET) is a new diagnostic procedure which allows to image tissue metabolism in vivo. Utilizing increased substrate metabolism or transport as a marker of malignant disease, primary as well as metastatic or recurrent lung cancer can be detected. This allows for improved differential diagnosis of pulmonary nodules or staging of non small cell lung cancer as has been documented in several studies. New applications of PET may include non-invasive evaluation of tissue proliferation or hypoxia to predict individual prognosis or treatment response.

FDG PET for staging of advanced non-small cell lung cancer prior to neoadjuvant radio-chemotherapy

The aim of this study was to evaluate positron emission tomography (PET) with fluorine-18 fluorodeoxyglucose (FDG) for the staging of non-small cell lung cancer (NSCLC) before combined neoadjuvant, i.e. preoperative, radio-chemotherapy (RCT). From November 1998 until September 2001, 101 patients with NSCLC were investigated prospectively. The inclusion criterion was a histologically proven NSCLC of stage IIIA or B according to conventional staging including biopsy. The results of PET were compared with those obtained by mediastinoscopy, computed tomography (CT), bone scan and abdominal ultrasonography. Validation of discrepant findings was achieved by biopsy or repeated CT. PET proved to be highly accurate for the detection of lymph node metastases (sensitivity 96%, specificity 73%, positive predictive value 88%, negative predictive value 89%, accuracy 88%) as well as distant metastases (in 25/101 patients, all previously unknown). PET findings changed further treatment in 29/101 patients (29%). Twenty-five were excluded from RCT due to the presence of previously unknown distant metastases. One patient was free of metastases and therefore was operated on without pre-treatment. Two patients did not receive any further treatment because a malignant tumour could be excluded after PET. In the final patient PET demonstrated a tumour pattern not typical for NSCLC which could be attributed to a seminoma after repeated biopsy. FDG PET is the most accurate non-invasive diagnostic procedure for the staging of advanced NSCLC. Therefore use of FDG PET is highly recommended in order to select patients for neoadjuvant or other stage-dependent treatment modalities.

[Secondary spontaneous pneumothorax in tuberous sclerosis]

Secondary pneumothorax occurs as a symptom of an underlying pulmonary disease. We report the case of an 18-year-old woman with tuberous sclerosis (Bourneville's disease) and recurrent pneumothoraces. Clinical outcome was favorable 6 months after bilateral videothoracoscopic pleurectomy. The complete triad of tuberous sclerosis (TS) (mental retardation, seizures, adenoma sebacium) is not always present in those who develop pulmonary involvement. When TS involves the lung it is clinically and pathologically indistinguishable from lymphangioleiomyomatosis (LAM). The very rare pulmonary involvement of TS and LAM are problems primarily of women in childbearing age. A pneumothorax can be the first symptom of TS or LAM.

[Endoluminal therapy of the trachea and bronchus]

The application of endoscopic techniques is common in the treatment of tracheal and bronchial diseases today. Bronchoscopic interventions are used in both elective and emergency situations. Laser therapy for malignant tumors is purely palliative in most cases and should only be performed in nonsurgical patients. However, 30% of lung cancers cause obstruction in the trachea and main bronchi. Benign tumors and tracheal stenoses could require laser recanalization or the implantation of stents, if surgery will be the second step or will not be possible. In patients with foreign body aspiration, massive hemoptysis, or severe obstruction of the trachea, emergency bronchoscopy is necessary. A more recent type of bronchoscopic intervention is the treatment of bronchial stump or anastomosis insufficiency as well as minimal iatrogenic injuries using spongiotic fillings or stent implantation. The use of therapeutic bronchoscopy requires great experience in rigid and flexible bronchoscopy, the possibility of high-frequency jet ventilation as well as laser and argon application, and the possibility to implant different types of stents. More advanced bronchoscopic interventions should only be done if a department of thoracic surgery exists, in view of the potential need to control complications or perform further treatment. Especially the bronchoscopic treatment of tracheal stenosis should be performed by the thoracic surgeon himself or in close contact with a thoracic surgeon who is experienced in tracheal resections.

Reduced blood loss by aprotinin in thoracic surgical operations associated with high risk of bleeding. A placebo-controlled, randomized phase IV study

OBJECTIVE

Although the blood-saving effect of aprotinin has been well documented in cardiac surgery and lung transplantation, its use in lung surgery has received less attention. We present our experience with the intraoperative application of aprotinin in lung resections with a predicted high risk of bleeding.

METHODS

Thirty-eight patients undergoing major thoracic surgical procedures were randomized into treatment and placebo groups. The treatment group (n=18) received a bolus of 2 x 10(6) kallikrein inhibitor units (KIU) of aprotinin followed by 5 x 10(5) KIU/h during surgery. The placebo group (n=20) received an isotonic saline infusion instead.

RESULTS

There was no significant difference between the groups concerning diagnosis, co-morbidity, age, sex, height, and weight. The mean intraoperative blood loss in the treatment group was significantly reduced (342 vs. 808 ml, P<0024), postoperative blood loss was also reduced (623 vs. 1282 ml, P<0.0007) and the need for blood transfusion was less (14 vs. 60, n.s.). No severe side effects of aprotinin were registered. Re-thoracotomy was necessary in two patients of the placebo group because of postoperative bleeding.

CONCLUSION

Aprotinin reduces the perioperative blood loss and the need for blood transfusion in thoracic surgical procedures in patients with an increased risk of bleeding.

Neoadjuvant chemoradiotherapy of stage III non-small-cell lung cancer

Twenty to 30% of patients with non-small-cell lung cancer (NSCLC) in stage III are not resectable primarily with 5-year survival less than 10%. Since the majority of patients die from metastases, efforts have been made in the past to improve prognosis by application of neoadjuvant chemoradiotherapy regimens followed by subsequent resection. In a phase II study performed between 1993 and 1998, 93 patients in stage III (IIIA, 16%; IIIB, 84%) received an induction chemotherapy consisting of two cycles cisplatin (100 mg/m2) and vindesine (3 mg/m2) with subsequent sequential radiotherapy of 36 Gy. Sixty-five patients demonstrated partial or complete remission. Sixty underwent surgery; in 49 of them complete resection was possible. Five-year survival in the whole group was 24%, and that in the surgical cohort 39%. Six patients had no residual tumor. Postoperative N0 status was associated with a 5-year survival of 75%, and stage N1-3 with 13%. Thirty-day mortality was 7% postoperatively. Neoadjuvant chemoradiotherapy can significantly improve long-term survival in stage III NSCLC with an acceptable therapy-induced mortality.

[Pharmacokinetics of cyclophosphamide, adriamycin and adriamycin prodrug (HMR 1928) using an ex vivo isolated perfused human lung model (IHLP)]

BACKGROUND

Today knowledge about pharmacokinetics of anticancer drugs in human malignant tumors is poor. Data from in vivo studies are limited and difficult to obtain due to ethical aspects. An ex vivo isolated perfused and ventilated human lung model however allows pharmacological studies of human bronchial carcinoma inside their host organ, the lung, under physiological conditions without compromising the patient.

METHODS

Following surgery for bronchial carcinoma human lung preparations were reperfused and ventilated extracorporally for 2-3 hours. During the reperfusion anticancer drugs are added to the perfusion solution and their uptake into tumor, normal lung tissue, and lymph nodes is studied.

RESULTS

An initial study showed that lung reperfusion under physiological circumstances over a period of 2-3 hours did not interfere with histo-pathological diagnostics and staging; an important precondition for potential adjuvant treatment. Pharmacokinetics of cyclophosphamid, adriamycin, and a water soluble adriamycin prodrug (HMR 1826) were measured. Final tissue concentrations of adriamycin and cyclophosphamid in peripheral lung parenchyma turned out to be 10 times higher compared to tumor tissue. However, following perfusion with adriamycin prodrug final tissue concentrations of adriamycin were in the same range in lung and tumor.

CONCLUSIONS

The ex-vivo isolated human lung perfusion model (IHLP) has proven to be an ideal scientific model for pharmacological investigations of human tumors as an intermediate step between cell culture and in-vivo situation without any disadvantage for the patient. The tumor-to-host interaction is completely saved in this model. However, first pass reactions of drugs in other organs must not play a role for the substances studied with the IHLP. The role and future applications of the isolated perfused human lung model for other indications is discussed.

Cystosarcoma phyllodes malignum: a case report of a successive triple modality treatment

This paper reports on a woman with a rapidly growing recurrent cystosarcoma phyllodes malignum after two major attempts of surgery. In this situation, neoadjuvant hyperfractionated radiotherapy, superficial hyperthermia and ifosfamide were administered. Toxicity was mild. Resection of the tumour bed revealed a pathologically complete response with an actual disease free follow-up of 48 months.

Variability of cyclophosphamide uptake into human bronchial carcinoma: consequences for local bioactivation

PURPOSE

The alkylating cytostatic prodrug cyclophosphamide is bioactivated by the human cytochrome P450 enzyme system. Since these enzymes are not only expressed in human liver, but also in extrahepatic tissue, local bioactivation of this drug may play an important role in its antineoplastic effects, e.g., chemotherapy of lung tumors. This would require uptake of significant amounts of cyclophosphamide into tumor tissue, which has not yet been demonstrated.

METHODS

We used a recently developed, ex vivo isolated, ventilated and perfused human lung model to study cyclophosphamide uptake into bronchial carcinoma and healthy lung tissue. Following a standard lobectomy, lung samples containing the tumor were perfused with buffer containing 2 mM cyclophosphamide for 2 h. Cyclophosphamide concentrations in perfusate and healthy peripheral tissue were measured during the perfusion and in tumors at the end of perfusion.

RESULTS

In all tissue samples, cyclophosphamide uptake was relatively poor, indicated by a tissue to perfusate ratio of 0.021. Moreover, in tumor samples, cyclophosphamide concentrations were significantly lower (P < 0.05) than in healthy lung tissue and showed pronounced interindividual variability. Median concentrations were 36.8 microg/g (26.9 44.2 microg/g) in healthy tissue and 5.1 microg/g (0.0-26.8 microg/g) in tumor samples. Tumor cyclophosphamide concentrations varied between 0 and 75% of those reached in healthy tissue.

CONCLUSIONS

Our results indicate that CP tumor concentrations are modulated by factors different from dose and that expression of bioactivating enzymes in human lung or transfection of genes encoding these enzymes into tumor cells does not necessarily lead to local bioactivation of cyclophosphamide.

Reliability of telepathology for frozen section service

One of the most promising applications of telepathology (pathology at a distance by electronic transmission of images in pathology) is frozen section diagnosis, especially because by means of this tool operations requiring an intraoperative histopathological diagnosis are feasible at hospitals without a pathologist on-site. For the introduction of this diagnostic tool into pathologist's daily practice the evidence of its diagnostic accuracy comparable to that of the conventional frozen section diagnosis is crucial. For this purpose the literature on the diagnostic accuracy of telepathological frozen section diagnosis was reviewed. In a metaanalysis these studies and reports, in which a total of more than 1290 cases had been examined, showed a slightly lower overall diagnostic accuracy (of the telepathological frozen section diagnosis) of about 0.91 than the conventional frozen section diagnosis with an average accuracy of about 0.98 found in an analysis of several studies (on frozen section diagnosis of different organs). This difference is at least predominantly caused by a higher rate of deferred and false negative frozen section diagnoses in the telepathological method, while the specificity of both methods, each more than 0.99 was not significantly different. In conclusion, the introduction of a telepathological frozen section diagnosis for hospitals without an acceptable access to a pathologist is justifiable already at the current state of the technological development especially when considering the advantages (time saving, reduction in costs) compared to the alternative of surgical interventions without access to an intraoperative diagnosis.

Ligands for Viscum album agglutinin and galectin-1 in human lung cancer: is there any prognostic relevance?

Viscum album agglutinin (VAA) is an extract component of mistletoe. It belongs to the plant lectin family and exerts various biological effects such as cytotoxic properties for tumor cells in culture. VAA as well as galectin-1, an endogenous lectin, possess galactose-specific surface-binding sites. We therefore investigated 159 cases of lung cancer for their capacity to bind VAA and galectin-1 and for Lewis antigen reactivity. Three different methods were used for detection of VAA: a two-step method with biotinylated VAA; an immune complex three-step method, and a four-step method. The most sensitive results were obtained with the four-step method utilising VAA, a goat-anti-VAA antibody and a biotinylated rabbit-anti-goat antibody. Intensity and distribution of staining were assessed using an immunoreactive score index (0-12). Approximately 70% of all tumors exhibited moderate to strong binding capacity for VAA. Adenocarcinomas and bronchiolo-alveolar carcinomas were more frequently labeled than squamous carcinomas. No relationship between expression of binding sites for VAA and galectin-1 as well as of Lewis antigens was found. Moreover, there was no correlation between VAA-binding capacity and survival, whereas expression of galectin-1-binding sites was of prognostic significance. Patients showing expression of galectin-1-binding sites revealed a better prognosis than those lacking binding sites or showing a weak reactivity (P = 0.0257 log rank test of Kaplan-Meier statistics).

[Resection of lung metastases: long-term results and prognostic analysis based on 5206 cases--the International Registry of Lung Metastases]

The International Registry of Lung Metastases was established in 1991 to asses the long-term results of pulmonary metastasectomy. The Registry has accrued 5206 cases of lung metastasectomy, from 18 departments of thoracic surgery in Europe (n = 13), USA (n = 4) and Canada (n = 1). Of these patients 4572 (88%) underwent complete surgical resection. The primary tumor was epithelial in 2260 (43%), sarcoma in 2173 (42%), germ cell in 363 (7%), and melanoma in 328 (6%) patients. The disease-free interval was 0 to 11 months in 1729 (33%) cases, 12 to 35 months in 1857 (36%) and more than 36 months in 1620 (31%). Single metastases accounted for 2383 (46%) cases and multiple lesions for 2726 (52%). Mean follow up was 46 months. Analysis was performed by Kaplan-Meier estimates of survival, relative risk of death and multivariate Cox model. The actuarial survival after complete metastasectomy was 36% at 5 years, 26% at 10 years and 22% at 15 years (median 35 months); the corresponding values for incomplete resection were 13% at 5 years and 7% at 10 years (median 15 months). Among complete resections, the 5-year survival was 33% for patients with a disease free-interval of 0 to 11 months and 45% for those with a disease-free interval of more than 36 months; 43% for single lesions and 27 for four or more lesions. Multivariate analysis showed a better prognosis for patients with germ cell tumors, disease-free interval of 36 months and more and single metastases. These results confirm that lung metastasectomy is a safe and potentially curative procedure.

[Video-assisted thoracoscopic access in pleural empyema compared with mere chest tube drainage]

Video-assisted thoracoscopic (VAT) debridement is gaining importance in the fibrino-purulent phase of empyema thoracis. However, evaluation of this access compared with mere chest tube drainage or thoracotomy remains unsatisfactory. A total of 356 parapneumonic empyemas from 1986 to 1997 were retrospectively analyzed concerning the results after primary treatment (chest tube 225, thoracotomy 80, VAT 51). The three groups did not differ significantly for gender and associated diseases. Median age of the chest tube drainage group (54 years) was higher than for thoracotomy (43.5 years) or VAT (39 years). Median duration of chest tube treatment after thoracotomy (7 days) was shorter than after VAT (13 days) or chest tube drainage (20 days) (P < 0.0001). The more invasive procedures were also superior to the lesser invasive treatment concerning duration of postoperative hospitalization, recurrence rate and treatment failures. In spite of its better results thoracotomy will be pushed back by VAT in the treatment of empyema thoracis. Acceptance of VAT is reflected in rising numbers of admissions. Based on these retrospective results we are planning a prospective multicenter trial to evaluate the indication for VAT in empyema thoracis.

Resection of pulmonary metastases from renal cell carcinoma

Between 1980 and 1995, 77 patients underwent complete resection of pulmonary metastases from a renal cell carcinoma after exclusion of a primary tumor recurrence and other metastatic localizations. 30-day mortality was 3%. The Median follow-up was 34 months (M). Cumulative 5-year survival (5-YS) was 39%. Prognostic criteria are the duration of the disease-free interval (DFI) and the number of metastases. Patients with a DFI > or = 48 M had a 5-YS of 46% compared to 26% for a DFI of < 48 M. Patients with a solitary metastasis had a 5-YS of 49% compared to 19% for multiple metastases. There was no significant difference in terms of sex, kind of access, kind of operation, and unilateral or bilateral affection. Since metastases from renal cell carcinomas are almost resistant to chemotherapy and radiotherapy and immunotherapy at present does not considerably improve long-term survival, surgical resection currently is the only effective therapeutic access in renal cell cancer metastasized to the lung.

Intraoperative thoracic sonography

In contrast to its use in other surgical disciplines, intraoperative sonography has so far been of minor importance in thoracic surgery. The technique of intrathoracic, intraoperative, ultrasonic examination was applied in 85 patients with different indications: in 61 patients during thoracoscopy, in 24 patients during open thoracic surgery. 6 patients eventually underwent a combination of both procedures. In order to improve the intrathoracic maneuverability of the sonographic probe we developed an electrically controllable handle for the probe. The examinations showed a high sensitivity of thoracoscopic ultrasonography for localization of intrapulmonary tumors. In addition, ultrasound was applied to assess the operability of central tumors. The sound frequency available so far for intraoperative application allows a safe distinction of non-infiltrating tumors from vascular structures; the reliable identification of an infiltration mostly requires a higher resolution. If our experiences are confirmed by further application of the method, explorative thoracotomies will surely be partly replaced by explorative thoracoscopic interventions. Ultrasonography has also proved to be useful in visualisation of mediastinal lymph-nodes and tumors, with the possibility of assessing their size.

[Assessment of current pleurodesis procedures exemplified by pneumothorax]

This survey addressed common methods of video-assisted thoracoscopic pleurodesis for spontaneous pneumothorax. A questionnaire asking for frequency, recurrence rate and complications of the different methods of pleurodesis was sent to all hospitals that belong to the German Society for Thoracic Surgery. 19 hospitals reported on a total of 1365 operations. 88 recurrences (6.5%), 26 severe bleeding complications (1.9%), 39 persisting air leaks (2.9%) and two hospital deaths (0.1%) had been observed. Pleurectomy and pleural abrasion were the most common procedures but induced significant (p = 0.01) more bleeding complications (3.1% and 2.6%) than all other methods of pleurodesis (0.4%). Overall recurrence rates depended significantly on the chosen procedure (p = 0.0013). Pleurectomy (4.4%) and coagulation of the pleura (2.7%) showed better results than the average. Due to smaller numbers of operations and the widely differing results this significance cannot be shown for the individual recurrence rates of the different clinics. This survey demonstrated a trend towards lower rates of recurrence and complications after coagulation of the pleura parietalis. The retrospective character of the investigation and extremely different recurrence rates for different hospitals demand cautious interpretation of these results.

Analysis of CYP2D6 expression in human lung: implications for the association between CYP2D6 activity and susceptibility to lung cancer

We have studied whether CYP2D6 is expressed in human lung tissue, using a specific and sensitive reverse transcriptase-polymerase chain reaction method and immunohistochemistry. Seven out of the eight patients were extensive metabolizers as shown by genotyping for the CYP2D6 (debrisoquine-sparteine) polymorphism. To investigate whether expression of CYP2D6 in lung tumours is different from that in normal lung tissue, tumour tissue samples were also obtained from the same eight patients. Correctly spliced CYP2D6 mRNA was detected by RT-PCR analysis in human liver and duodenum but not in any of the lung samples. In accordance with these negative results, immunoreactivity for CYP2D6 protein, using specific monoclonal and polyclonal antibodies, was very low or absent. No specific cell type of lung tissue showed strong immunoreactivity for CYP2D6, although expression of CYP3A could be clearly demonstrated in the same tissue samples. Moreover, a Western blot analysis revealed no signal in lung microsomes from two additional extensive metabolizers. Taken together, these results indicate that expression of CYP2D6 in human lung is absent or very low. These findings thus argue against a significant local metabolic activation of procarcinogenic agents by CYP2D6 in the lung.