Protective effect of height on long-term survival of resectable lung cancer: a new feature of the lung cancer paradox

INTRODUCTION

Unlike most malignancies, higher body mass index (BMI) is associated with a reduced risk of lung cancer and improved prognosis after surgery. However, it remains controversial whether height, one of determinants of BMI, is associated with survival independently of BMI and other confounders.

METHODS

We extracted data on all consecutive patients with resectable non-small cell lung cancer included in Epithor, the French Society of Thoracic and Cardiovascular Surgery database, over a 16-year period. Height was analysed as a continuous variable, and then categorised into four or three categories, according to sex-specific quantiles. Cox proportional hazards regression was used to estimate the association of height with survival, adjusted for age, tobacco consumption, forced expiratory volume in one second (FEV1), WHO performance status (WHO PS), American Society of Anesthesiologists (ASA) score, extent of resection, histological type, stage of disease and centre as a random effect, as well as BMI in a further analysis.

RESULTS

The study included 61 379 patients. Higher height was significantly associated with better long-term survival after adjustment for other variables (adjusted HR 0.97 per 10 cm higher height, 95% CI 0.95 to 0.99); additional adjustment for BMI resulted in an identical HR. The prognostic impact of height was further confirmed by stratifying by age, ASA class, WHO PS and histological type. When stratifying by BMI class, there was no evidence of a differential association (p=0.93). When stratifying by stage of disease, the prognostic significance of height was maintained for all stages except IIIB-IV.

CONCLUSIONS

Our study shows that height is an independent prognostic factor of resectable lung cancer.

Impact of surgical approach on 90-day mortality after lung resection for nonsmall cell lung cancer in high-risk operable patients

Introduction

Non-small cell lung cancer (NSCLC) is often associated with compromised lung function. Real-world data on the impact of surgical approach in NSCLC patients with compromised lung function are still lacking. The objective of this study is to assess the potential impact of minimally invasive surgery (MIS) on 90-day post-operative mortality after anatomic lung resection in high-risk operable NSCLC patients.

Methods

We conducted a retrospective multicentre study including all patients who underwent anatomic lung resection between January 2010 and October 2021 and registered in the Epithor database. High-risk patients were defined as those with a forced expiratory volume in 1 s (FEV1) or diffusing capacity of the lung for carbon monoxide (DLCO) value below 50%. Co-primary end-points were the impact of risk status on 90-day mortality and the impact of MIS on 90-day mortality in high-risk patients.

Results

Of the 46 909 patients who met the inclusion criteria, 42 214 patients (90%) with both preoperative FEV1 and DLCO above 50% were included in the low-risk group, and 4695 patients (10%) with preoperative FEV1 and/or preoperative DLCO below 50% were included in the high-risk group. The 90-day mortality rate was significantly higher in the high-risk group compared to the low-risk group (280 (5.96%) versus 1301 (3.18%); p<0.0001). In high-risk patients, MIS was associated with lower 90-day mortality compared to open surgery in univariate analysis (OR=0.04 (0.02-0.05), p<0.001) and in multivariable analysis after propensity score matching (OR=0.46 (0.30-0.69), p<0.001). High-risk patients operated through MIS had a similar 90-day mortality rate compared to low-risk patients in general (3.10% versus 3.18% respectively).

Conclusion

By examining the impact of surgical approaches on 90-day mortality using a nationwide database, we found that either preoperative FEV1 or DLCO below 50% is associated with higher 90-day mortality, which can be reduced by using minimally invasive surgical approaches. High-risk patients operated through MIS have a similar 90-day mortality rate as low-risk patients.

The Reality of Lung Cancer Paradox: The Impact of Body Mass Index on Long-Term Survival of Resected Lung Cancer. A French Nationwide Analysis from the Epithor Database

Obesity could have a protective effect in patients with lung cancer. We assessed the prognostic role of preoperative BMI on survival in patients who underwent lung resection for NSCLC. A total of 54,631 consecutive patients with resectable lung cancer within a 15-year period were extracted from Epithor (the French Society of Thoracic and Cardiovascular Surgery database). Patient subgroups were defined according to body mass index (BMI): underweight (BMI < 18.5 kg/m²), normal weight (18.5 ≤ BMI < 25 kg/m²), overweight (25 ≤ BMI < 30 kg/m²), and obese (BMI ≥ 30 kg/m²). Underweight was associated with lower survival (unadjusted HRs 1.24 (1.16-1.33)) compared to normal weight, whereas overweight and obesity were associated with improved survival (0.95 (0.92-0.98) and 0.88 (0.84-0.92), respectively). The impact of BMI was confirmed when stratifying for sex or Charlson comorbidities index (CCI). Among patients with obesity, a higher BMI was associated with improved survival. After adjusting for period of study, age, sex, WHO performance status, CCI, side of tumor, extent of resection, histologic type, and stage of disease, the HRs for underweight, overweight, and obesity were 1.51 (1.41-1.63), 0.84 (0.81-0.87), and 0.80 (0.76-0.84), respectively. BMI is a strong and independent predictor of survival in patients undergoing surgery for NSCLC.

Induction of resident memory T cells enhances the efficacy of cancer vaccine

Tissue-resident memory T cells (Trm) represent a new subset of long-lived memory T cells that remain in tissue and do not recirculate. Although they are considered as early immune effectors in infectious diseases, their role in cancer immunosurveillance remains unknown. In a preclinical model of head and neck cancer, we show that intranasal vaccination with a mucosal vector, the B subunit of Shiga toxin, induces local Trm and inhibits tumour growth. As Trm do not recirculate, we demonstrate their crucial role in the efficacy of cancer vaccine with parabiosis experiments. Blockade of TFGβ decreases the induction of Trm after mucosal vaccine immunization, resulting in the lower efficacy of cancer vaccine. In order to extrapolate this role of Trm in humans, we show that the number of Trm correlates with a better overall survival in lung cancer in multivariate analysis. The induction of Trm may represent a new surrogate biomarker for the efficacy of cancer vaccine. This study also argues for the development of vaccine strategies designed to elicit them.

Can mathematics replace anatomy to establish recommendations in lung cancer surgery?

The greater the number of lymph node (LN) sampled (NLNsS) during lung cancer surgery, the lower the risk of underestimating the pN-status and the better the outcome of the pN0-patients due to stage-migration. Thus, regarding LN sampling "to be or not to be", number is the question. Recent studies advocate removing 10 LNs. The most suitable NLNsS is unfortunately impossible to establish by mathematics. A too high NLNsS variability exists, based on anatomy, surgery and pathology. The methodology may vary according to Inter-institutional differences in the surgical approach regarding LN inspection and number sampling. The NLNsS increases with the type of resection: sublobar, lobectomy or pneumonectomy. Concerning pathology, one LN may be divided into several pieces, leading to number overestimation. The pathological examination is limited by the number of slices analyzed by LN. The examined LNs can arbitrarily depend on the probability of detecting nodal metastasis. In fact, the only way to ensure the best NLNsS and the best pN-staging is to remove all LNs from the ipsilateral mediastinal and hilar LN-stations as they are discovered by thoroughly dissecting their anatomical locations. In doing so, a deliberate lack of harvest of LNs is unlikely, number turns out not to be the question anymore and a low NLNsS no longer means incomplete surgery. This prevents from judging as incomplete a complete LN dissection in a patient with a small NLNsS and from considering as complete a true incomplete one in a patient with a great NLNsS. Precise information describing the course of the operation and furnished in the surgeon's reports is also advisable to further improve the quality of LN-dissection, which ultimately might be beneficial in the long-term to patients. However, that procedure is of limited interest in pN-staging if LNs are not thoroughly examined and also described by the pathologist.

Composite biomarkers defined by multiparametric immunofluorescence analysis identify ALK-positive adenocarcinoma as a potential target for immunotherapy

Anaplastic lymphoma kinase (ALK) inhibitors have been successfully developed for non-small cell lung carcinoma (NSCLC) displaying chromosomal rearrangements of the ALK gene, but unfortunately resistance invariably occurs. Blockade of the PD-1-PD-L1/2 inhibitory pathway constitutes a breakthrough for the treatment of NSCLC. Some predictive biomarkers of clinical response to this therapy are starting to emerge, such as PD-L1 expression by tumor/stromal cells and infiltration by CD8⁺ T cells expressing PD-1. To more effectively integrate all of these potential biomarkers of clinical response to immunotherapy, we have developed a multiparametric immunofluorescence technique with automated immune cell counting to comprehensively analyze the tumor microenvironment of ALK-positive adenocarcinoma (ADC). When analyzed as either a continuous or a dichotomous variable, the mean number of tumor cells expressing PD-L1 (p = 0.012) and the percentage of tumor cells expressing PD-L1 were higher in ALK-positive ADC than in EGFR-mutated ADC or WT (non-EGFR-mutated and non-KRAS-mutated) NSCLC. A very strong correlation between PD-L1 expression on tumor cells and intratumoral infiltration by CD8⁺ T cells was observed, suggesting that an adaptive mechanism may partly regulate this expression. A higher frequency of tumors combining positive PD-L1 expression and infiltration by intratumoral CD8⁺ T cells or PD-1⁺CD8⁺ T cells was also observed in ALK-positive lung cancer patients compared with EGFR-mutated (p = 0.03) or WT patients (p = 0.012). These results strongly suggest that a subgroup of ALK-positive lung cancer patients may constitute good candidates for anti-PD-1/-PD-L1 therapies.

Chest wall resection for multifocal osseous haemangioma

Intraosseous haemangioma is a rare and benign primary tumour of the bone. We report the case of a 76-year old woman who presented the exceptional condition of multifocal cavernous haemangiomas involving the spine and the ribs, requiring spinal and chest wall resections to confirm the diagnosis and treat the symptoms.

Time trends in surgery for lung cancer in France from 2005 to 2012: a nationwide study

The aim of this study was to assess the evolution of survival in patients treated surgically for non-small cell lung cancer (NSCLC) between 2005 and 2012.From January 2005 to December 2012, 34 006 patients underwent pulmonary resection for NSCLC and were included in the French national database Epithor. Patients' characteristics, procedures and survival were analysed. Survival according to the management was evaluated for each 2-year period separately: 2005-2006, 2007-2008, 2009-2010 and 2011-2012.The proportions of early-stage cancers and adenocarcinomas increased significantly over the periods. 3-year overall survival (OS) increased significantly from 80.5% for the first period to 81.4% for the last period. For the periods 2005-2006 and 2007-2008, 3-year OS was lower after segmentectomy than after lobectomy (77 and 73% versus 82 and 83%, respectively). For the periods 2009-2010 and 2011-2012, 3-year OS in the two sub-groups was similar. OS after bi-lobectomy or pneumonectomy was lower than after lobectomy for all periods analysed. Systematic nodal dissection increased OS for all periods. Chemotherapy but not radiotherapy improved OS in the first 12 postoperative months for all periods.Changes in histological type and stage linked to advances in surgical and medical practices since 2005 led to an increase in OS in patients with surgical-stage NSCLC.

Pre- and post- transplantation lung cancer in heart transplant recipients

Heart transplantation after lung cancer surgery can be questionable because of the high risk of cancer recurrence. We report the results of two patients. The first underwent right lobectomy in 2008 for pT1N0 adenocarcinoma, heart-transplantation in 2010, and surgery for synchronous adenocarcinoma and squamous-cell carcinoma in 2012. The second underwent left segmentectomy for pT1aN0 adenosquamous carcinoma and transplantation in 1995 and then surgery for pT1aN1 adenocarcinoma in 2013. Posttransplantation lung cancer histologic analysis results were different in both cases, demonstrating the absence of metastatic recurrence. Thus, early stage lung cancer might not be a contraindication to heart transplantation, nor are long delays be necessary before registering on a waiting list.

Pneumonectomy for benign disease: indications and postoperative outcomes, a nationwide study

OBJECTIVES

Pneumonectomy for benign disease is rare but is thought to have a higher more postoperative morbidity and mortality than when performed for lung cancer. We questioned this by assessing and analysing indications and postoperative outcomes of patients who underwent this type of resection.

METHODS

We used Epithor, the French national thoracic database including 91 public and private institutions with more than 220 000 procedures. We prospectively collected data of 5975 patients who underwent pneumonectomy between January 2003 and June 2013. The 321 patients (5.4%) who underwent pneumonectomy (n = 201) or completion pneumonectomy (n = 120) for benign disease were compared with those treated for malignant disease.

RESULTS

The patients' mean age was 55.2 years (53.5; 56.8) for benign indications vs 61.6 years (61.4; 61.9) for malignant disease; the sex ratio was 1.8 (207 males) and 4 (4543 males), respectively; 53% of patients (n = 169) had an American Society of Anesthesiologist (ASA) score of ≥3 vs 29% (n = 1598) for malignant disease. For benign disease, most frequent indications were infection or abscess (n = 114, 37.1%), post-tuberculosis destroyed lung (n = 47, 15.3%), aspergillosis or aspergilloma (n = 33, 10.7%), bronchiectasis (n = 41, 13.3%), haemorrhage (n = 26, 8.5%) and benign tumour (n = 20, 6.5%). Complications occurred in 53% (n = 170) of patients and the postoperative in-hospital mortality rate was 22.1% (n = 71). These results were significantly worse than those for malignant indications: 38.9% (n = 2198) of morbidity (P < 0.0001) and 5.1% (n = 288) of in-hospital mortality (P < 0.0001). For benign disease, there was no difference in fistula formation regarding side (P = 0.07) or type of resection (P = 0.6). Morbidity was higher for completion pneumonectomy: 62.5 vs 47.3% (P = 0.008). Mortality was significantly higher in case of resection for infection or abscess (P = 0.01) and for haemorrhage (P = 0.002). Emergency procedures were associated with worse postoperative outcomes (P < 0.0001).

CONCLUSIONS

Pneumonectomy for benign disease achieves cure with very high levels of morbidity and mortality. This type of surgical treatment should be considered as a salvage procedure.

Current readings: the most influential and recent studies regarding resection of lung cancer in m1a disease

M1A disease is a recent concept appearing in the 7th TNM classification of lung cancer. M1A encompasses two different entities, malignant pleural or pericardial effusions and separate tumor nodules in the contralateral lung, who constitute very different diseases, with very different management and prognoses. On one hand, patients with pleural dissemination have extremely poor survival, with median and 5-year survivals of 4 months and 3.1%, respectively. Only selected patients whose limited pleural extension has been diagnosed at the time of thoracotomy and completely resected, may experience prolonged survival. On the other hand, recent progress in molecular biology still failed to establish whether a contralateral lesion is a second primary or a metastasis. These contralateral lesions are now gathered as multiple lung cancers in the surgical literature, and misleadingly classified as M1A disease in the TNM classification. Patients with contralateral nodules may experience prolonged survival after the surgical treatment of both localizations. Changing the staging by establishing the diagnosis of metastasis is probably an important issue warranting further biologic research, but according to current results this diagnosis must not in any case preclude surgery.

Number of mediastinal lymph nodes in non-small cell lung cancer: a Gaussian curve, not a prognostic factor

BACKGROUND

It has been proposed that examining a greater number of lymph nodes (LNs) in patients with non-small-cell lung cancer (NSCLC) treated by surgical resection may increase the likelihood of proper staging and affect outcome. Our purpose was to evaluate the interindividual variability and prognostic relevance of the number of LNs harvested during complete pulmonary and mediastinal lymphadenectomy performed for NSCLC.

METHODS

We prospectively collected and retrospectively reviewed the data from 1,095 patients who underwent lung cancer resection in association with systematic lymphadenectomy and pulmonary and mediastinal LN counts from 2004 to 2009. We analyzed the interindividual variability and prognostic impact of the number of LNs on overall survival (OS).

RESULTS

The mean number of harvested pulmonary and mediastinal LNs was 17.4±7.3 (range, 1-65) and was higher in male patients, right lung surgical procedures, lobectomy and pneumonectomy, N2 disease, and pIII stage. The mean number of harvested mediastinal LNs was 10.7±5.6 and was normally distributed (range, 0-49; median, 10). The 5-year survival rate was 53.8%. Overall survival was influenced by the number of involved stations (single-station versus multi-station disease, 5-year survival rates 31.5% versus 16.9%, respectively; p=0.041) but not by the number of harvested LNs, the number of harvested mediastinal LNs, or the number of positive mediastinal LNs.

CONCLUSIONS

After lung cancer resection and complete lymphadenectomy, the number of LNs is subject to normally distributed interindividual variability, with no significant impact on OS. Recommending an optimal number of nodes is therefore arbitrary. Instead, our recommendation is to perform a complete systematic pulmonary and mediastinal lymphadenectomy following established anatomical boundaries.

Long-term survival of patients with pN2 lung cancer according to the pattern of lymphatic spread

BACKGROUND

N2 involvement has dramatic consequences on the prognosis and management of patients with non-small cell lung cancer (NSCLC). N2-NSCLC may present with or without N1 involvement, constituting non-skip (pN1N2) and skip (pN0N2) diseases, respectively. As the prognostic impact of this subclassification is still a matter of debate, we analyzed the prognosis of pN2 patients according to the pN1-involvement and the number of N2-stations concerned.

METHODS

The medical records of consecutive patients who underwent surgery for pN2-NSCLC in 2 French centers between 1980 and 2009 were prospectively collected and retrospectively reviewed. Patients undergoing induction therapy, exploratory thoracotomy, incomplete mediastinal lymphadenectomy, or incomplete resections were excluded. The prognoses of pN1N2 and pN0N2 patients were first compared, and then deciphered according to the number of N2 stations involved (single-station: 1S, multi-station: 2S).

RESULTS

All together, 871 patients underwent first-line complete surgical resection for pN2-NSCLC during the study period, including 258 pN0N2 (29.6%) and 613 pN1N2 (70.4%) patients. Mean follow-up was 72.8±48 months. Median, 5- and 10-year survivals were, respectively, 30 months, 34%, and 24% for pN0N2 and 20 months, 21%, and 14% for pN1N2 patients (p<0.001). Multivariate analysis revealed 3 different prognostic groups; ie, favorable in pN0N2-1S disease, intermediate in pN0N2-2S and pN1N2-1S diseases, and poor in pN1N2-2S disease (p<0.001).

CONCLUSIONS

Among pN2 patients, the combination of N1 involvement (pN0N2 vs pN1N2) and number of involved N2 stations (1S vs 2S) are independent prognostic factors. These results might be taken into consideration to sub-classify the heterogeneous pN2-NSCLC group of patients.

High grade neuroendocrine lung tumors: pathological characteristics, surgical management and prognostic implications

Among non-small cell lung cancers (NSCLC), large cell carcinoma (LCC) is credited of significant adverse prognosis. Its neuroendocrine subtype has even a poorer diagnosis, with long-term survival similar to small cell lung cancer (SCLC). Our purpose was to review the surgical characteristics of those tumors. The clinical records of patients who underwent surgery for lung cancer in two French centers from 1980 to 2009 were retrospectively reviewed. We more particularly focused on patients with LCC or with high grade neuroendocrine lung tumors. High grade neuroendocrine tumors were classified as pure large cell neuroendocrine carcinoma (pure LCNEC), NSCLC combined with LCNEC (combined LCNEC), and SCLC combined with LCNEC (combined SCLC). There were 470 LCC and 155 high grade neuroendocrine lung tumors, with no difference concerning gender, mean age, smoking habits. There were significantly more exploratory thoracotomies in LCC, and more frequent postoperative complications in high grade neuroendocrine lung tumors. Pathologic TNM and 5-year survival rates were similar, with 5-year ranging from 34.3% to 37.6% for high grade neuroendocrine lung tumors and LCC, respectively. Induction and adjuvant therapy were not associated with an improved prognosis. The subgroups of LCNEC (pure NE, combined NE) and combined SCLC behaved similarly, except visceral pleura invasion, which proved more frequent in combined NE and less frequent in combined SCLC. Survival analysis showed a trend toward a lower 5-year survival in case of combined SCLC. Therefore, LCC, LCNEC and combined SCLC share the same poor prognosis, but surgical resection is associated with long-term survival in about one third of patients.

Adenosquamous carcinoma of the lung: surgical management, pathologic characteristics, and prognostic implications

BACKGROUND

Adenosquamous carcinoma (ASC) is a mixed glandular and squamous cell carcinoma with a more aggressive behavior than the other histologic subtypes of lung cancer. We revisited the pathologic characteristics and surgical results associated with ASC.

METHODS

Patients who underwent surgical resection of non-small cell lung cancer in two French centers were retrospectively reviewed. Patients presenting with ASC (n=141) were compared to those with adenocarcinomas (AC, n=2415) and squamous cell carcinomas (SCC, n=2662) regarding preoperative data, histologic characteristics, and outcome.

RESULTS

The frequency of ASC and SCC decreased over time. ASC patients were similar to AC patients regarding age, sex, and smoking habits. The type of resections performed in ASC patients was intermediary between SCC (more pneumonectomy) and AC (more lobectomy) patients. ASC was associated with larger size, more frequent visceral pleura invasion, microinvasion of the lymphatic vessels, and ipsilateral second nodules, compared with SCC and AC. Among the 135 patients with documented ASC, 48% presented with a combination of AC and SCC tumor cells ranging between 40% and 60% of each component, and 55% of cases were associated with undifferentiated large cells. ASC was associated with a lower 5-year survival rate (37%) than SCC and AC (43.4% and 42.8%, respectively, p=0.017). For ASC patients, survival was better during the last decade or in cases of balanced AC/SCC components.

CONCLUSIONS

ASC is characterized by both histologic aggressiveness and adverse prognosis. In this setting, the impact of adjuvant therapies needs to be reevaluated.

Prognosis of lung cancer resection in patients with previous extra-respiratory solid malignancies

OBJECTIVES

Non-small-cell lung cancer (NSCLC) following pulmonary or pharyngolaryngeal malignancies has been widely studied, but only a few articles have focussed on lung cancers following other solid malignancies. Our purpose was to compare the characteristics and prognosis of patients with NSCLC according to the medical history of the extra-pulmonary and extra-pharyngolaryngeal solid malignancy.

METHODS

Patients who underwent surgery for NSCLC from January 1980 to December 2009 in two French thoracic centres were reviewed. We compared patients with no history of cancer (Group 1) and patients with a history of extra-pulmonary and extra-pharyngolaryngeal solid malignancy (Group 2).

RESULTS

There were 4992 patients: 4603 (92%) in Group 1 and 389 (8%) in Group 2. In comparison with Group 1, Group 2 showed an increasing incidence over the last 3 decades (2-8%), an older population (65.9 vs 61 years, P < 0.001), a higher proportion of women (34 vs 18%, P < 0.001), non-smokers (20 vs 10%, P < 0.001), adenocarcinomas (53 vs 40%, P < 0.001), T1 (16 vs 14%, P = 0.047) and second nodule in the same lobe (4 vs 2%, P < 0.001). The overall survival was not significantly different between the two groups (P = 0.09). In multivariate analysis, older age, male gender, pneumonectomy, higher T, higher N, incomplete resection and history of extra pulmonary-extra pharyngolaryngeal solid malignancy were significantly associated with a worse prognosis.

CONCLUSIONS

Despite an earlier diagnosis, a history of extra-pulmonary and extra-pharyngolaryngeal solid malignancy is associated with a worse prognosis in patients with NSCLC undergoing surgical resection. Overall survival is particularly low after a history of bladder and upper gastrointestinal malignancies.

Unexpected extensions of non-small-cell lung cancer diagnosed during surgery: revisiting exploratory thoracotomies and incomplete resections

OBJECTIVES

Only patients with a complete resection of non-small-cell lung cancer (NSCLC) may expect long-term survival. Despite the recent progress in imaging and induction therapy, a thoracotomy may remain exploratory or with incomplete resection (R2). Our purpose was to revisit these situations.

METHODS

A total of 5305 patients who underwent surgery for NSCLC between 1980 and 2009 were reviewed. We compared the epidemiology, pathology, causes and prognosis characteristics of exploratory thoracotomy (ET) and R2 resections.

RESULTS

ET and R2 resections were observed in 223 (4%) and 197 (4%) patients, respectively. The frequency of ET decreased with time, while the frequency of R2 resection remained almost stable. The indications for ET and R2 resections were not significantly different. In comparison with ET, R2 resections were characterized by a significantly higher frequency of induction therapy (22 vs 17%, P < 10(-3)), adenocarcinomas (49 vs 15%, P < 10(-6)), T1-T2 (53 vs 29%, P < 10(-6)) and N0-N1 extension (67 vs 42%, P = 10(-6)). R2 resections were also characterized by a higher rate of postoperative complications (19.1 vs 9.9%, P = 0.014), with no significant difference in postoperative mortality (6.9 vs 4.9%, P = non significant). R2 resections resulted in a higher 5-year survival compared with ET (11.1 vs 1.2%, P = 10(-3)). There was no long-term survivor after ET, except during the last decade.

CONCLUSIONS

ET and R2 remain unavoidable. In comparison with ET, R2 resection is associated with a higher rate of postoperative complications, but a higher long-term survival.

Evolving characteristics of lung cancer: a surgical appraisal

OBJECTIVE

Lung cancer management has changed due to emergence of new imaging techniques and of multimodal therapies. Our purpose was to analyse how lung cancer evolved in surgical practice.

METHODS

The records of patients who underwent surgical resection for lung cancer from 1983 to 2006 in two centres were reviewed. Data were split into four time periods of 6 years. We analysed and compared the epidemiological, pathological and prognostic characteristics of each period.

RESULTS

There were 832, 1148, 1493 and 1195 patients during the periods 1983-88, 1989-94, 1995-2000 and 2001-06, respectively. The main changed characteristics were increasing numbers of older patients, females, past history of another cancer and/or cardio-vascular disease, adenocarcinomas and undifferentiated large-cell carcinomas, smaller tumour size, T1-T2, N0 (47.2-61.2%) and neoadjuvant therapy (NAT) (3.8-24.9%). There were also a decreasing number of exploratory thoracotomies, pneumonectomies and adjuvant therapy (AT) (48.5-30%). The 5-year survival rates improved (34.5-46.3%, P < 10(-6)), mainly after lobectomy, and in the case of adenocarcinoma, N0 and N2 patients. Multivariate analysis confirmed that time trend was an independent factor of prognosis (P < 10(-6)), just as important as N involvement, complete resection (R0), tumour size, age, another cancer history and more significant than the type of resection, histology, NAT and AT.

CONCLUSIONS

During the last 25 years, the clinico-pathological features of operated patients have progressively changed and the results following surgery improved. Earlier stage diagnosis might explain overall survival improvement, and play a more major role than associated peri-operative treatments. Therefore, it is advisable to consider the time-related factor in future studies on lung cancer surgery.

Mesothelioma at era of helical tomotherapy: results of two institutions in combining chemotherapy, surgery and radiotherapy

PURPOSE

There is a scarce clinical experience about adjuvant helical tomotherapy (HT) in patients affected by malignant pleural mesothelioma (MPM) even though it appears as a useful technique to treat complex volume as the pleural cavity, and seems to have better dose distribution than the "classic" intensity modulated radiotherapy (IMRT).

METHODS AND MATERIALS

Twenty-four patients received adjuvant radiotherapy (RT) by HT from August 1st, 2007 to December 1st, 2009 at Curie Institute (Paris) and René Gauducheau Cancer Center (Nantes). Thirteen patients had neoadjuvant chemotherapy. Extrapleural pleuropneumonectomy (EPP) was done in 23 patients. Median dose to PTV was 50Gy [48.7-55.9Gy] (2Gy/fraction). Acute and long term toxicities, disease free survival (DFS), overall survival (OS) and relapses are presented.

RESULTS

Average follow up after RT was 7 months. The disease was staged mostly as T2-T3, N1-N2. Nineteen patients had epithelial type histology. Most patients tolerated radiotherapy with grade 1-2 side effects: redness of the skin, light cough or dyspnea, fatigue, nausea and odynophagia, mild increase of the post-operative thoracic pain. Grade 3 pneumonitis was suspected in 2 patients. Two grade 5 pneumonitis were also suspected. Eleven patients had a follow up of more than 6 months and no long term side effects related with HT were noted. At 24 months, 51.8% of patients were free of disease. Thirty percent of patients relapsed, with 2 patients presenting local relapses. Two patients died from recurrence.

CONCLUSION

With limited follow up, HT has comparable toxicity to those observed with traditional IMRT. Higher radiation dose and good coverage results in excellent local control.

Surgery for metastatic pleural extension of non-small-cell lung cancer

OBJECTIVE

Malignant cells in the pleural fluid or pleural metastases are now classified stage IV in lung cancer and alter the treatment. Our purpose was to question the role of surgery in such patients.

METHODS

The clinical records of 4668 patients, who underwent lung cancer surgery, were reviewed. In some, an undiagnosed pleural malignant disease (M1a) was discovered during thoracotomy. When feasible, selected patients underwent complete surgical resection of the primary tumor and pleural nodules. We analyzed the epidemiology, pathology, and prognosis characteristics of that group (study group), as compared with the population undergoing pulmonary resection in a curative attempt (overall population) or exploratory thoracotomy in case of unexpected disseminated carcinomatous pleuritis (control group).

RESULTS

The study group included 32 patients (25 males), mean age 59 ± 8.8 years, who underwent pneumonectomy (n = 9) or lobectomy (n = 23), associated with mediastinal lymph nodes dissection and surgical resection of associated pleural nodules. There were 21 adenocarcinomas, seven squamous cell carcinomas, two undifferentiated large cell carcinomas, and two miscellaneous tumors. Pathological node (pN) was: N0 in 10 patients (31.3%), N1 in four (12.5%), and N2 in 18 (56.3%). Five-year survival rate was 16% after resection, and 21% if the resection was a lobectomy.

CONCLUSION

Complete surgical resection of non-small-cell lung cancer (NSCLC) associated with limited metastatic pleural involvement is associated with long-term survival in 16% of the cases. A review of the published data, together with the results of this series, may justify the inclusion of surgery in multimodality treatment of NSCLC patients with metastatic pleural extension.

Lung cancer invading the pericardium: quantum of lymph nodes

BACKGROUND

Lung cancer may invade the pericardium (T3) and the intrapericardial pulmonary veins and left atrium (T4). Our purpose was to analyze the characteristics of this invading process in search of the reasons explaining its poor prognosis.

METHODS

The clinical records of 4,668 patients who underwent surgery for lung cancer between January 1983 and December 2006 in two thoracic surgery centers were retrospectively reviewed. The epidemiology, pathology, and prognostic characteristics of the tumors invading the pericardium alone (T3) or with pulmonary veins and atrium (T4) were analyzed and compared with all other tumors.

RESULTS

There were 75 male and 16 female patients, with 85 pneumonectomies and 6 lobectomies that proved R0 in 59.3% of patients, and contained 69 squamous cell cancers, 11 adenocarcinomas, and 13 miscellaneous tumors; 12 were N0 (13.2%), 31 were N1 (34.1%), and 48 were N2 (52.8%). Pericardium alone was invaded in 32 patients (35.2%), and with pulmonary vein and atrium in 34 (37.3%) and 25 (27.5%), respectively. Patient characteristics were similar in each group. Five-year and 10-year survival rates were 15.1% and 10.4%, respectively. Frequency of pneumonectomy, R1-2 resection, and N1-2 involvement were significantly more important compared with noninvading tumors (p < 10(-6)).

CONCLUSIONS

Reports on T3 and T4 cancer with pericardial involvement are few, but also stress that pulmonary vein and left atrium invasion does not worsen the prognosis more than pericardial invasion alone. The rich pericardial lymph drainage might enhance the spread of tumor cells, explaining excessively high N1-N2 rates and pericardial invasion-related poor prognosis.

Prognostic classifications of lymph node involvement in lung cancer and current International Association for the Study of Lung Cancer descriptive classification in zones

The lymphatic drainage of solid organ tumors crosses through the lymph nodes (LNs) whose tumoral involvement may still be considered as local disease. Concerning lung cancer, LN involvement may be intrapulmonary (N1), and mediastinal and/or extra-thoracic. More than 30 years ago, mediastinal involved LNs were all considered as N2, and outside the scope of surgery. In 1978, Naruke presented an original article entitled 'Lymph node mapping and curability at various levels of metastasis in resected lung cancer', demonstrating that N2 was not a contraindication to surgery in all patients. The map permitted to localize the favorable N2 on the lung cancer ipsilateral side of the mediastinum. Several maps ensued aiming to discriminate between right and left involvement (1983), and to distinguish N2 (ipsilateral) and N3 (contralateral) mediastinal LN involvement (1983, 1986). The last map (1997 regional LN classification) was recently replaced by a descriptive classification in anatomical zones. This new LN map of the TNM classification for lung cancer is a step toward using anatomical view points which might be the best way to better understand lung cancer lymphatic spread. Nowadays, the LNs are easily identified by current radiological imaging, and their resectability may be anticipated. Each LN chain may be removed by en-bloc lymphadenectomy performed during radical lung resection, a safe procedure which seems to be more oncological based than sampling, and which avoids the source of discrepancies pointed out during the labeling of LN stations by surgeons.

Pulmonary resection for metastases of colorectal adenocarcinoma

BACKGROUND

Surgery is a safe and effective treatment for patients with lung metastases from colorectal carcinoma. Combining chemotherapy and surgery seems to prolong survival time after metastasectomy. Our purpose was to review the effectiveness of surgery with time and evolving managements.

METHODS

The records of 127 patients were retrospectively analyzed. The characteristics of primary cancer, lung metastases, resections, and associated therapy were studied according to their incidence on survival.

RESULTS

There were 74 male and 53 female patients (mean age, 65 years); 223 operations were performed and 314 metastases were resected. Completeness of surgery (n = 117) was the main factor for prolonged survival (5- and 10-year survival, 41% and 27%, versus 0%). There was no factor of significantly better prognosis, but a tendency to higher survival rates was observed in cases of single metastasis, in patients undergoing several lung operations, and in patients in whom liver metastases were previously removed. Three of 7 patients with mediastinal lymph node involvement survived more than 5 years; 58 patients were operated on before January 2000, and 59 between January 2000 and December 2007. Five-year survival rates were 35.1% versus 63.5%, respectively (p = 0.0096), probably related to better selection with modern workup, more frequent use of chemotherapy, and repeated pulmonary resections.

CONCLUSIONS

Different treatment protocols were reported in the literature and in our series with time, resulting in better survival rates and a more aggressive surgical tendency. The beneficial role of such combined therapy justifies further research, including prospective trials.

Current indications and results for thoracoplasty and intrathoracic muscle transposition

OBJECTIVES

Thoracoplasty has lost much of its popularity and is being supplanted by space-reduction operations using muscle flaps. Our purpose is to retrospectively study the remaining indications and the evolving modifications of this ancient technique in our current surgical practice.

PATIENTS AND METHODS

From 1994 to 2008, 35 patients underwent a thoracoplasty procedure in a single thoracic surgery centre for treatment of infectious complications of previous thoracic surgery. The number and length of ribs excised were dictated by the size and location of the thoracic cavity to obliterate. Muscle flaps were used to buttress bronchial fistulas and to fill out residual spaces. We reviewed the immediate and long-term results concerning infection control and procedure tolerance.

RESULTS

The infectious complications of previous thoracic surgery were related to cancer in 25, tuberculosis in six, oesophageo-pleural fistula in two, ruptured lung abscess and pleural thickening in one each. The thoracoplasty procedure was performed for: (1) post-pneumonectomy empyema, n=20 (bronchial fistula, n=11; open window thoracostomy, n=14; mean number of resected ribs, n=7.5; associated intrathoracic muscle transposition, n=12; postoperative death, n=3); (2) post-lobectomy empyema, n=8 (bronchial fistula n=8; open window thoracostomy n=1; mean number of resected ribs n=3.6; associated intrathoracic muscle transposition n=7; no death); (3) other indications, n=7 (mean number of resected ribs n=4.8; associated intrathoracic muscle transposition n=3; no death). All patients discharged from the hospital except one were cured and did not complain of symptoms of secondary lung function and shoulder impairment.

CONCLUSION

Although thoracoplasty is rarely indicated nowadays, this does not imply that the procedure should be avoided. Thoracoplasty may be associated with myoplasty, which permits achieving complete space obliteration by combining resection of a few rib segments and limited intrathoracic muscle transposition.

Completely resected non-small cell lung cancer: reconsidering prognostic value and significance of N2 metastases

BACKGROUND

Non-small cell lung cancer (NSCLC) mediastinal (N2) metastases are indicators of poor prognosis. Survival rates decrease with increasing number of N2 stations and involved lymph nodes as well as lymph node size and capsular invasion. Our purpose was to elucidate the impact lymph node-related variables on the outcome after surgical resection.

METHODS

We reviewed data of 2344 NSCLC patients who underwent curative resections with mediastinal lymphadenectomy, and 586 (25%) had N2 metastases. We studied the overall survival of N2 patients according to some important covariates.

RESULTS

Metastases involved single N2 stations in 386 patients (66%) and two or more in 200 (34%). Survival was not related with histology or pathologic tumor (pT), but was better when only one N2 station was involved (5-year overall survival 28.5% [median, 24 months] versus 17.2% [median, 14 months] respectively; p = 0.0002. For single N2 stations, capsular rupture, number, and size of lymph nodes were not significant prognostic factors. When the size of lymph node was analyzed (micrometastases, 53; nonbulky, 207; or bulky metastases, 126), overall survival differences between nonbulky and bulky N2 were significant: 5-year overall survival was 34% (median, 28 months) versus 23% (median, 23 months), respectively (p = 0.026). Presence of micrometastases was associated with a poor prognosis: 5-year overall survival of 21.4% (median, 23 months).

CONCLUSIONS

Prognosis was better for patients with single N2 stations when metastatic lymph nodes were not enlarged. However, the presence of lymph nodes micrometastases does not seems associated with a better outcome.

Prognostic factors and surgical indications of pulmonary epithelioid hemangioendothelioma: a review of the literature

BACKGROUND

Pulmonary epithelioid hemangioendothelioma is a rare vascular tumor of low-grade malignancy, the prognosis of which remains unpredictable. The purpose of this analysis based on 80 patients was to determine prognostic factors and to evaluate results of surgery.

METHODS

We recorded data of 75 patients from reports published in the English and French literature using the terms "intravascular bronchoalveolar tumor" or "pulmonary epithelioid hemangioendothelioma" or a combination of both. We added to this database 5 more cases of pulmonary epithelioid hemangioendothelioma operated on in our thoracic surgery department from 1989 to 2005. Univariate and multivariate analyses of prognostic factors were performed using the log rank test and the Cox model. The factors we tested were age, sex, clinical symptoms, biologic and radiologic findings, and surgical treatment.

RESULTS

There were 49 women and 31 men with a mean age of 39.7 years (range, 7 to 72 years). The 5-year survival probability was 60% (range, 47% to 71%). Univariate analysis showed that loss of weight, anemia, pulmonary symptoms, and more particularly pleural hemorrhagic effusions were significant factors of poor prognosis, with a median survival of less than 1 year. Multivariate analysis showed a statistically worse survival in patients with hemorrhagic symptoms (hemoptysis, p < 0.0001; pleural effusion, p < 0.0001).

CONCLUSIONS

Pulmonary epithelioid hemangioendothelioma typically occurs among young patients. Surgery can be proposed in cases of unilateral single or multiple nodules. There is no single effective treatment in cases of bilateral multiple nodules. Lung transplantation should be evaluated in patients with vascular aggressivity with pleural hemorrhagic effusion and anemia.

Sleeve Lobectomy Versus Pneumonectomy: Tumor Characteristics and Comparative Analysis of Feasibility and Results

BACKGROUND

Sleeve lobectomy (SL) seems to have better results than pneumonectomy. Some authors propose to extend its indications. The aim of this study was to compare postoperative results, locoregional recurrence, and survival after sleeve lobectomy and pneumonectomy in focusing on right upper lobe cancer.

METHODS

From 1984 to 2002, 973 lung resections were performed for T1, T2, and bronchial T3 right upper lobe non-small cell lung cancer. There were 756 lobectomies (L group), 151 pneumonectomies (RP group), and 66 sleeve lobectomies (SL group). The RP group was further divided with regard to intrapulmonary lymph node involvement. Pneumonectomy 1 (RP1) was a group of N0, intralobar N1, and skip metastasis involvement (N0-N2). Pneumonectomy 2 (RP2) was a group of extralobar N1 and nonskip metastasis involvement (N1-N2). Postoperative results were compared among SL, L, and RP groups. Survival was compared between the two homogeneous groups for oncologic characteristics (SL, RP1).

RESULTS

Statistical comparison of 5-year actuarial survival showed a significant difference favoring SL (SL: 72.5%/ RP1: 53.2%; p = 0.0025). Postoperative mortality was higher after RP (L: 2.9% / SL: 4.5%/ RP: 12.6 %). Significant factors limiting SL were tumor size, extralobar N1, and main bronchus involvement (p = 0.000026, 0.0002, and 0.005, respectively).

CONCLUSIONS

Immediate and long-term survival appears better after sleeve lobectomy than right pneumonectomy for comparable stages of right upper lobe cancer. For frequency to increase by systematic attempt at SL, limited by large tumors and extralobar N1 involvement, the only way should be after favorable response to induction chemotherapy.

Skip mediastinal lymph node metastasis and lung cancer: a particular N2 subgroup with a better prognosis

BACKGROUND

Lymph node (LN) metastases from lung cancer may skip the intrapulmonary nodes directly to the mediastinum ([N1-]N2 vs [N1+]N2). This phenomenon is frequent. Patients with such a metastatic pattern appear to have a better prognosis following surgery. Our purpose was to further study the clinical significance and prognostic value of this particular group of (N1-)N2 patients.

METHODS

We retrospectively analyzed the data of 731 patients with a pN2 stage who underwent resection for non-small cell lung cancer. Patients with (N1-)N2 metastases (n = 209) were compared to patients with intrapulmonary (N1+)N2 (n = 522).

RESULTS

In the (N1-)N2 group, lobectomies were more frequent (54% vs 33%, p = 0.00), metastases more frequently involved a single LN station (79.4% vs 56.3%, p < 0.000001), and primary tumor was more often located in the upper lobes (67.4% vs 55.6%, p = 0.0066). (N1-)N2 was a factor of better prognosis (5 year survival rates 34.4% vs 18.5%, p = 0.00006), which proved also significant when only a single station was involved (38.4% vs 24%, p = 0.0005). These results were confirmed by multivariate analysis.

CONCLUSIONS

(N1-)N2 skip metastasis is a unique subgroup of pN2 disease. Lung lymph drainage anatomy may explain the occurrence of these metastases. They form an independent prognostic factor of survival suggesting the need for further study, the results of which may lead to better knowledge of lung cancer, improved classification, and adapted adjuvant therapy.

Immediate and Long-Term Survival After Surgery for Lung Cancer in Heart Transplant Recipients

BACKGROUND

Lung cancer observed after heart transplantation is considered to have a poor prognosis. However, the results of surgical treatment have not yet been significantly evaluated. This retrospective study analyzed the immediate and long-term results after surgery.

METHODS

From May 1990 to December 2003, 25 heart transplant recipients underwent surgery for lung cancer. There were 22 men and 3 women, the mean age was 60.7 years (49-72). All patients had a smoking history. Lung tumors were discovered by routine chest roentgenograms and computed tomography scans in 17 patients (68%), because of clinical symptoms in 7 (28%), and incidentally in 1 (4%). The surgical procedures consisted of 23 lobectomies and 2 wedge resections.

RESULTS

The mean postoperative hospital stay was 14.2 days (5-34). The morbidity rate was 28% (n = 7 patients). The mortality rate was 12% patients (n = 3 patients). The postoperative complications in 7 of 10 patients were mainly from infectious origin. Five-year survival rate was 40.9% with a median survival of 45 months. Seven patients died during follow-up (3 from cancer and 4 from other diseases). Significant better survival was observed in N0 patients than in N+ patients (median survival of 56.8 months in N0 vs 13.5 months in N+ patients (p = 0.017).

CONCLUSIONS

Long-term results after surgery were satisfactory in early stage disease, despite a high risk for postoperative infection. Our results underline the efficiency of a close follow-up for transplant recipients with a smoking history, leading to cancer detection at an early stage.

Recurrent pleural effusion complicating liver cirrhosis

BACKGROUND

Pleural effusion (PE) is a rare complication of advanced liver cirrhosis, which may lead to an operation when uncontrolled. The purpose of this study was to evaluate the modality of the occurrence of pleural effusion and to describe its surgical management.

METHODS

We studied 21 patients who were referred to the department of thoracic surgery because of massive and recurrent PE caused by liver cirrhosis. The PE was a transudate in 16 patients and an exudate in 5. Talc pleurodesis was attempted in all patients. The patients were divided into two groups. Video assisted thoracoscopy was performed in 13 patients in whom the clinical condition permitted general anesthesia; the pleural cavity was entirely explored before pleurodesis (group 1). Chest tube drainage alone was performed in 8 patients who were unable to undergo general anesthesia; talc pleurodesis was performed through the chest tube in these patients (group 2).

RESULTS

In group 1 the PE was right-sided in 8 patients, left-sided in 3, and bilateral in 2. Diaphragmatic defects were observed in 2 patients, and a fluid leak oozing from the diaphragm was observed in 1 patient. Ten patients were considered cured and were without recurrence. Two patients underwent late recurrence before dying from their liver cirrhosis. Only 1 patient had an early recurrence that was cured by complementary talc slurry. In group 2 all patients presented with a right PE; of these, 3 patients died from septic shock caused by pleural infection. Three patients underwent early recurrence but were cured after repeat talc slurry. One patient had a midterm recurrence. One patient had an early recurrence treated by intrahepatic porto-systemic shunt with partial improvement.

CONCLUSIONS

Passage of ascites through diaphragmatic defects appears to be the main cause of PE complicating cirrhosis. Patients may benefit from talc pleurodesis. Video assisted thoracoscopy pleurodesis is the technique of choice with consistent results. Repeated talc injection through the drain may prove useful for patients in poor clinical status.

Catamenial pneumothorax: retrospective study of surgical treatment

BACKGROUND

Catamenial pneumothorax is a rare entity characterized by recurrent accumulation of air in the thoracic space during menstruation. Catamenial pneumothorax is also associated with a high rate of postoperative recurrence. The aim of this study was to discuss the etiology and to determine the optimal surgical treatment of this entity.

METHODS

From December 1991 to September 2000, 10 patients with catamenial pneumothorax were treated at our institution. Median age at time of operation was 37 years (range, 21 to 44 years). We retrospectively evaluated the pathologic findings, the operation performed, and the results in all patients. The mean follow-up was 55.7 months.

RESULTS

Pleurodesis alone was performed in 5 patients and an associated diaphragmatic procedure was performed in 5 patients. In 5 patients, no diaphragmatic anomaly was discovered: 3 experienced one or more recurrences and all still suffer from chronic catamenial chest pain. Hormonal therapy temporarily improved outcome for 6 months in 2 patients. On the contrary, in 5 patients surgical pleurodesis was associated with the repair of diaphragmatic defects (simple closure or coverage by a polyglactin mesh): these patients experienced no recurrence (n = 0/5, p = 0.0016) and no subsequent catamenial chest pain.

CONCLUSIONS

The postoperative outcome is influenced by the diagnosis of diaphragmatic defects with or without endometriosis. Surgical treatment should be accomplished during menstruation for an optimal visualization of pleurodiaphragmatic endometriosis. Because diaphragmatic lesion is frequent and may be occult, we propose the systematic coverage of the diaphragmatic surface by a polyglactin mesh to prevent catamenial pneumothorax recurrence even when the diaphragm appears normal.

Visceral pleura invasion and pleural lavage tumor cytology by lung cancer: a prospective appraisal

BACKGROUND

Despite an early-stage diagnosis, lung cancer presenting with visceral pleura invasion (VPI) or malignant pleural lavage cytology (PLC) has a poor prognosis. The purpose of this study was to correlate VPI to malignant PLC.

METHODS

One hundred forty-three consecutive patients scheduled for surgical lung resection having undergone preresectional pleural lavage cytology were reviewed. There were 121 malignant and 22 nonmalignant lesions. All cases were studied by pathology, histology, previous transthoracic puncture, VPI, and presence of pleural lymphatic involvement.

RESULTS

PLC was positive (n = 13) or suspected (n = 5) for malignant cells in, respectively, 10.7% and 4.1% of patients with lung cancer. There was no positive PLC in cases of nonmalignant disease. PLC was positive only in pT2 tumors and almost always when the tumor was exposed on the pleural surface, thus possibly exfoliating within the pleural space (12/17 patients, 70.6%; p < 0.01). Positive PLC was obtained whatever the histology but did not appear related to previous transthoracic puncture or involvement of pleural lymphatics by tumor cells.

CONCLUSIONS

VPI and positive PLC are linked, and the appearance of tumor cells within the pleural cavity can be explained by tumor desquamation. The role that visceral pleura involvement and parietal pleura reabsorption play in lung cancer is of paramount importance and deserves further research. A better understanding of their relationship could have major implications in the therapeutic management of non-small cell lung cancer.

[Chylothorax]

PHYSIOLOGY: Chylothorax corresponds to the intrathoracic presence of chyle. Chyle is a lymph of intestinal origin containing the product of digested fat. This lymph joins the blood circulation through the thoracic duct. The thoracic duct receives a part of the lymphatic drainage from the viscera below the diaphragm, from the diaphragm and from the sterno-costal wall.

PHYSIOPATHOLOGY

Intrapleural chyle issue is explained by an acquired or spontaneous lesion of the thoracic duct or of one of its collaterals in the thorax. The iatrogenic or spontaneous lesions of the collaterals suggest that the latter are incontinent and have lost their valve capacity, and hence provoke a reflux of chyle from the thoracic duct. The anatomy of the chylothorax (occasionally pathological) can be specified by a pedal lymphography. FROM A THERAPEUTIC POINT OF VIEW: Treatment, essentially medical, can be completed by surgery. The medical treatment is based on re-nutrition and a diet excluding fat, supplemented by medium chain triglycerides. Surgery consists in pleural symphysis and/or suture of the damaged collaterals, or ligature of the thoracic duct. The indications depend on the severity of the chyle leakage and the type of original lesion. The indications therefore depend on the etiology and clinical evolution of each case. These different treatments, isolated or combined, lead to the regression of the effusion in nearly all cases.

Thoracic duct tributaries from intrathoracic organs

BACKGROUND

The thoracic duct (TD) is the main collecting vessel of the lymphatic system. Little is known about the intrathoracic tributaries of the TD, which are named intercostal, mediastinal, and bronchomediastinal trunks. The purpose of the study was to identify the lymphatic tributaries from intrathoracic organs to the thoracic duct.

METHODS

The study was performed on 530 adult cadavers. The lymphatics of different organs were catheterized and injected with a dye: lungs (n = 360), heart (n = 90), esophagus (n = 50), and diaphragm (n = 30). The lymphatic tributaries draining the lymph from these organs to the thoracic duct were dissected along their course to the thoracic duct and classified.

RESULTS

The TD tributaries were observed in 147 cases: right lung (n = 46), left lung (n = 69), heart (n = 8), esophagus (n = 13), and diaphragm (n = 11). Connections with the TD were observed at its origin (n = 13), within the mediastinum (n = 87), and at the level of the TD arch (n = 47). Tributaries from the lung issued from lower paratracheal nodes 4 R (n = 14) and 4 L (n = 31), subaortic 5 (n = 4), subcarinal 7 (n = 18), pulmonary ligament 9 (n = 7), upper tracheal 2 L (n = 28), paraortic 6 (n = 11), and celiac nodes (n = 2). Tributaries from the heart connected with the TD in the mediastinum in 1 case (4 L) and with the TD arch in 7 cases. Tributaries from the esophagus connected with the thoracic duct within the mediastinum in 13 cases; anodal routes were frequent (n = 5). The TD tributaries from the diaphragm were observed in 11 cases, always connecting with the TD at its origin.

CONCLUSIONS

Injection of intrathoracic organs permits visualization of TD tributaries. These tributaries appear located at unchanging levels. Lymph of intrathoracic organs may thus drain into the general circulation through the TD. The tributaries may represent a potential route for tumor cells dissemination. When incompetent, due to valve insufficiency, they permit chylous lymph to backflow into the intrathoracic lymph nodes. Injury at this level may lead to intrathoracic chylous effusions.