Carcinoid tumours of the lung and the 'PEPPS' approach: evaluation of preoperative bronchoscopic tumour debulking as preparation for subsequent parenchyma-sparing surgery

Pneumonectomy for broncho-pulmonary carcinoids: a single centre analysis of surgical approaches and patient outcomes

Background

Pneumonectomy is a radical surgical procedure associated with significant morbidity and mortality. Its application in the context of pulmonary neuroendocrine tumours, including carcinoid tumours, requires meticulous preoperative planning and intraoperative precision. This study aims to assess the safety and efficacy of pneumonectomy in the management of these rare and challenging neoplasms.

Methods

A retrospective analysis of patients who underwent pneumonectomy for pulmonary carcinoid tumours at our institution over a specified period was conducted. Data regarding patient demographics, tumour characteristics, surgical techniques, intraoperative complications, perioperative management, and long-term outcomes were collected and analysed.

Results

Between March 2001 and October 2022, 21 patients (7 male, 14 female) with carcinoid tumours underwent pneumonectomy on a total of 459 surgical operations for carcinoid. Preoperative bronchoscopic procedures were conducted in 90.4% of cases, leading to histological diagnoses for most. The median hospital stay was eight days, with no reported perioperative deaths. Median follow-up after surgery was 73 months, with a five-year overall survival of 65.4 months. Recurrences occurred in 28.6% of cases, primarily in atypical carcinoids.

Conclusion

Despite the rarity of bronchial carcinoids, pneumonectomy is effective for low-grade malignancies, demonstrating positive short-and long-term outcomes. Radical lymph node dissection is fundamental in pathological staging and overall survival.

[Isolated bronchoplastic procedure for typical carcinoid of the left lung]

Lung carcinoids (LC) comprise neuroendocrine lung tumors of low (typical carcinoid) and intermediate (atypical carcinoid) grade of malignancy accounting for less than 2% of all lung neoplasms. In Europe, annual incidence of LC varies from 0.2 to 2 per 100 000. This value increased dramatically over the past 30 years. One of the causes is improvement of diagnostic methods. Compared to aggressive high-grade neuroendocrine lung cancer, natural course of early-stage LC is usually indolent. Therefore, surgery with preservation of as much normal lung tissue as possible is preferable for resectable tumors. Nevertheless, the number of isolated bronchial resections with preservation of the entire lung tissue is relatively small, and these procedures remain technically complex interventions. We present isolated resection of interlobular spur, lower medial wall of distal part of the left main bronchus and proximal part of the lower lobular bronchus for typical carcinoid with monobronchial anastomosis and preservation of the entire lung parenchyma.

Diagnosis of atypical carcinoid can be made on biopsies > 4 mm2 and is accurate

In the 2021 WHO thoracic tumors, gradation of lung carcinoids in biopsies is discouraged. We hypothesized that atypical carcinoid (AC) could be reliably diagnosed in larger preoperative biopsies. Biopsy-resection paired specimens of carcinoid patients were included, and definitive diagnosis was based on the resection specimen according to the WHO 2021 classification. A total of 64 biopsy-resection pairs (26 typical carcinoid (TC) (41%) and 38 AC (59%)) were analyzed. In 35 patients (55%), tumor classification between the biopsy and resection specimen was concordant (26 TC, 9 AC). The discordance in the remaining 29 biopsies (45%, 29 TC, 0 AC) was caused by misclassification of AC as TC. In biopsies measuring < 4 mm², 15/15 AC (100%) were misclassified compared to 14/23 AC (61%) of biopsies ≥ 4 mm². Categorical concordance of Ki-67 in biopsy-resection pairs at threshold of 5% was 68%. Ki-67 in the biopsy was not of additional value to discriminate between TC and AC, irrespective of the biopsy size. Atypical carcinoid is frequently missed in small bronchial biopsies (< 4 mm²). If the carcinoid classification is clinically relevant, a cumulative biopsy size of at least 4 mm² should be considered. Our study provides strong arguments to make the diagnosis of AC in case of sufficient mitosis for AC on a biopsy and keep the diagnosis "carcinoid NOS" for carcinoids with ≤ 1 mitosis per 2 mm². Ki-67 has a good concordance but was not discriminative for definitive diagnosis.

Confocal endomicroscopy and robot-assisted bronchoplasty integration to treat an endobronchial tumour

We present a case of a young man with an endobronchial carcinoid in the left main bronchus, which was treated integrating probe-based confocal laser endomicroscopy and fluorescence imaging during a robot-assisted bronchoplasty. This technique allowed precise detection of the neoplastic area, avoiding associated lung resection. The incorporation of new technologies to our current practice may lead to a better approach to airway tumours.

Bronchoscopic diagnosis and treatment of endobronchial carcinoid: case report and review of the literature

Carcinoid tumours are rare neuroendocrine neoplasms that mostly occur in younger adults with low tendencies to metastasise. Based on their histological characteristics, they are divided into typical and atypical subtypes. The most common presenting symptoms are due to central airway obstruction. The first step in the diagnostic assessment should be a computed tomography (CT) scan, as it provides information both for local tumour extent and lymph node involvement. Bronchoscopy is the main tool for histological confirmation, evaluation of bronchial wall invasion and removal of endobronchial manifestation with subsequent resolution of atelectasis. Endobronchial ultrasound may be necessary to rule out lymph node metastasis. Somatostatin receptor scintigraphy in combination with CT can rule out further metastatic disease.Surgical resection using parenchyma-sparing techniques remains the gold standard for treatment. For selected patients, endobronchial therapy could be an alternative for minimal invasiveness. Long-term follow-up is suggested due to the high likelihood of recurrence.Here, we describe our clinical experience in a 35-year-old male patient who originally presented with haemoptysis and a central polypoid tumour in the left main bronchus revealed by a CT scan. The histological characteristics were indicative of a typical carcinoid. The patient was treated using an endobronchial approach only. No complications and no recurrences have been observed in a follow-up of 2 years.

Recent Advances in the Management of Typical and Atypical Lung Carcinoids

Neuroendocrine neoplasms of the lung represent about 20% to 30% of all neuroendocrine tumors. On the basis of clinical and pathologic characteristics, 2 different categories of tumors may be defined: poorly differentiated neuroendocrine neoplasms, characterized by a high rate of recurrences and poor prognosis, and well-differentiated neuroendocrine neoplasms (typical carcinoids and atypical carcinoids), which generally display an indolent course. Lung carcinoids represent only 1% to 5% of all lung malignancies, but their incidence has significantly increased over the past 30 years. Surgery is the reference standard of treatment for lung carcinoids with locoregional disease. For advanced or unresectable lung carcinoids, several therapeutic options are available, but the choice should be shared within a multidisciplinary team to ensure optimal therapeutic outcomes. We describe the current management of these rare neoplasms.

Endobronchial and surgical treatment of pulmonary carcinoid tumors: A systematic literature review

The treatment of pulmonary carcinoid has changed over the last decades. Although surgical resection is still the gold standard, minimally invasive endobronchial procedures have emerged as a parenchyma sparing alternative for tumors located in the central airways. This review was performed to identify the optimal treatment strategy for pulmonary carcinoid, with a particular focus on the feasibility and outcome of parenchyma sparing techniques versus surgical resection. A systematic review of the literature was carried out using MEDLINE, Embase and the Cochrane databases, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. Two separate searches of publications in endobronchial and surgical treatment in patients with pulmonary carcinoid, were performed. Outcomes were overall survival, disease free survival, recurrence rate, complications, quality of life, and healthcare costs. Combining the two main searches for endobronchial therapy and surgical therapy yielded 3111 records. Finally, 43 studies concerning surgical treatment and 9 studies related to endobronchial treatment for pulmonary carcinoid were included. Assessment of included studies showed that lymph node involvement, histological grade, tumor location and tumor diameter were identified as poor prognostic factors and seem to be important for patients with pulmonary carcinoid. For patients with a more favorable prognosis, tumor location and tumor diameter are important factors that can help decide on the optimal treatment strategy. Centrally located small intraluminal pulmonary carcinoids, without signs of metastasis can be treated with minimally invasive alternatives such as endobronchial treatment or parenchyma sparing surgical resection. Patients with parenchyma sparing resections should be followed with long term follow up to exclude recurrence of disease. In a multidisciplinary setting, it should be determined whether individual patients are eligible for parenchyma sparing procedures or anatomical resection. Overall evidence is of low quality and future studies should focus on prospective trials in the treatment of pulmonary carcinoid.

Multimodality multistaged management of large endobronchial carcinoid causing respiratory failure: A case report with review of literature

We report the case of a 58-year-old female presenting with central airway obstruction leading to airway compromise thrice, first two times from endobronchial growth of typical carcinoid tissue and subsequently from granulation tissue at anastomotic site after left carinal pneumonectomy. Bronchoscopic resection of carcinoid tumor and granulation tissue was performed successfully with electrosurgical snaring through rigid bronchoscope. Cryodebridement using flexible cryoprobe of the tumor was done postembolization and of the remnant granulation tissue without any complication. A multimodality approach is required for favorable outcome as observed in this case.

Catheter-based endobronchial electroporation is feasible for the focal treatment of peribronchial tumors

OBJECTIVE

To evaluate the feasibility of catheter-based endobronchial electroporation for the treatment of peribronchial tumors and assess the incidence of treatment-related adverse events.

METHODS

Cytotoxicity of electroporation with or without cisplatin or gefitinib was assessed in vitro with lung cancer and normal cell lines. A novel catheter was designed for endobronchial electroporation, and computer simulations were used to predict in vivo treatment effects. Electroporation with the test catheter was performed (2000 V, 70 pulses) in the main bronchus of 8 pigs at 11 locations. Computed tomography imaging was performed before they were killed at 4 hours (6 animals) or 4 weeks (2 animals) posttreatment. Treated airway and surrounding parenchyma were compared with sham treatment via gross and histopathology.

RESULTS

Significant cell death due to electroporation and increased cytotoxicity in combination with cisplatin or gefitinib were observed in cancer cells only (P < .05). Simulations predicted penetrative electroporation of peribronchial parenchyma without tissue heating. Electric pulse delivery in vivo induced transient venous and bronchial spasms that resolved without intervention. Cross-sectional measurement of electroporation effects on computed tomography (14.4 ± 1.4 by 10.5 ± 1.3 mm) and gross pathology (17.2 ± 3.0 by 8.8 ± 0.6 mm) were representative of values predicted by simulation (P < .001). Cell death due to irreversible electroporation was observed in bronchial and parenchymal tissue in acute tissue samples. Treated lung rapidly recovered from the effects of electroporation without change in bronchial patency at 4 weeks posttreatment.

CONCLUSIONS

Catheter-based endobronchial electroporation is a reproducible technique that can be used to treat peribronchial tumors in combination with cisplatin, without affecting patency of the treated bronchus.