Robotic hiatal hernia repair without mesh.

Background: Newer minimally invasive techniques have supplanted laparotomy and thoracotomy for management of hiatal hernias. Limited data exists on outcomes after robotic hiatal hernia repair without mesh despite the increasing popularity of this approach. We report our high-volume experience with durable robotic hiatal hernia repair with gastric fundoplication without mesh. Methods: A retrospective review was conducted on patients with type I-IV hiatal hernias who underwent an elective robotic-assisted repair from 2016 to 2019 using a novel technique of approximating the hiatus with running barbed absorbable (V-locTM) suture and securing it with interrupted silk sutures. Main outcomes included length of stay, readmission rate, and recurrence rate. Results: A total of 144 patients were reviewed. The average age of the patient was 61 years. Most of the patients were female [95 females (66%) to 49 males], and the average body mass index (BMI) was 29.96 kg/m2. The average operating time was 173 minutes (standard deviation 62 minutes). The average length of stay in the hospital was 2 days, and 89% of patients went home within the first 3 days. Ten patients (6.9%) were readmitted within 30 days, there were no mortalities in 30 days, and there were 6 (4.2%) recurrences on follow up requiring reoperation. Conclusions: Elective robotic hiatal hernia repair with fundoplication and primary closure of the hiatus with V-locTM and nonabsorbable suture without mesh is safe and effective. The robotic approach has similar operative times, lengths of stay, and complications compared to nationally published data on laparoscopic hiatal hernia repairs.

Safety and usability of an endo staple line reinforcement device for pulmonary resections.

Background: Pulmonary resection can present technical challenges for surgeons due to the dissection and closure of tissues, which vary in thickness and elastic properties, occasionally leading to prolonged air leaks. Staple line reinforcements (SLRs) are widely utilized tools for fortifying the stability and integrity of closures in thoracic surgery, however, materials available and ease of use for both surgeon and scrub nurse have been suboptimal. A novel "click-and-go" device pre-loaded with bioabsorbable buttress material was recently developed, the Echelon Endopath SLR (ESLR, Ethicon, Inc., Cincinnati, OH, USA). This prospective study examines the safety and efficacy of this novel device in lung resections. Methods: Adult surgical candidates undergoing primary pulmonary resection (both open and thoracoscopic) where the ESLR would be used were enrolled. Exclusion included reoperation/revision in same anatomical location, hypersensitivity to polyglactin or related products, and body mass index (BMI) ≥46.0 kg/m2. The primary endpoint assessed the incidence of specific device-related adverse events (AEs): prolonged air leak and empyema. Additional endpoints included number of devices replaced during surgery due to slippage or bunching, and surgeon-reported usability responses. Data was summarized for AEs deemed device-related and usability questionnaire responses. Results: A total of 131 subjects were included in the primary endpoint analysis data set with 120 subjects completing the study (91.6%). The mean age at consent was 62.8±12.0 years and 55.7% were female. The most common primary indication for the procedure was malignancy 61.1%, and primary non-malignant lung disease (non-chronic obstructive pulmonary disease) 12.2%. Common procedures performed were wedge resection (58.0%) and lobectomy (34.4%). There were zero reported device-specific/-related AEs which counted toward the primary endpoint. Responses from a usability questionnaire found all surgeons (100.0%) reported the ease of setup was superior to previous devices utilized. Surgeons expressed greater confidence in the buttress material of the ESLR than that of previous SLR devices (strongly agree 88.9%; slightly agree 11.1%). Most also felt that there was less wastage with the click-and-go ESLR (strongly agree 77.8%, slightly agree 11.1%, neutral 11.1%). Conclusions: The ESLR device demonstrates safe and effective performance in this post-market study of specific thoracic procedures. Furthermore, surgeons found this was easier to use.

A two-stage in vivo approach for implanting a 3D printed tissue-engineered tracheal replacement graft: A proof of concept.

OBJECTIVES: To optimize a 3D printed tissue-engineered tracheal construct using a combined in vitro and a two-stage in vivo technique. METHODS: A 3D-CAD (Computer-aided Design) template was created; rabbit chondrocytes were harvested and cultured. A Makerbot Replicator™ 2x was used to print a polycaprolactone (PCL) scaffold which was then combined with a bio-ink and the previously harvested chondrocytes. In vitro: Cell viability was performed by live/dead assay using Calcein A/Ethidium. Gene expression was performed using quantitative real-time PCR for the following genes: Collagen Type I and type II, Sox-9, and Aggrecan. In vivo: Surgical implantation occurred in two stages: 1) Index procedure: construct was implanted within a pocket in the strap muscles for 21 days and, 2) Final surgery: construct with vascularized pedicle was rotated into a segmental tracheal defect for 3 or 6 weeks. Following euthanasia, the construct and native trachea were explanted and evaluated. RESULTS: In vitro: After 14 days in culture the constructs showed >80% viable cells. Collagen type II and sox-9 were overexpressed in the construct from day 2 and by day 14 all genes were overexpressed when compared to chondrocytes in monolayer. IN VIVO: By day 21 (immediately before the rotation), cartilage formation could be seen surrounding all the constructs. Mature cartilage was observed in the grafts after 6 or 9 weeks in vivo. CONCLUSION: This two-stage approach for implanting a 3D printed tissue-engineered tracheal replacement construct has been optimized to yield a high-quality, printable segment with cellular growth and viability both in vitro and in vivo.

Biomechanical properties of the ex vivo porcine trachea: A benchmark for three-dimensional bioprinted airway replacements.

PURPOSE: Combining tissue engineering and three-dimensional (3D) printing may allow for the introduction of a living functional tracheal replacement graft. However, defining the biomechanical properties of the native trachea is a key prerequisite to clinical translation. To achieve this, we set out to define the rotation, axial stretch capacity, and positive intraluminal pressure capabilities for ex vivo porcine tracheas. STUDY DESIGN: Animal study. MATERIALS AND METHODS: Six full-length ex vivo porcine tracheas were bisected into 5.5 cm segments. Maximal positive intraluminal pressure was measured by sealing segment ends with custom designed 3D printed caps through which a pressure transducer was introduced. Axial stretch capacity and rotation were evaluated by stretching and rotating the segments along their axis between two clamps, respectively. RESULTS: Six segments were tested for axial lengthening and the average post-stretch length percentage was 148.92% (range 136.81-163.48%, 95% CI 153-143%). The mean amount of length gain achieved per cartilaginous ring was 7.82% (range 4.71-10.95%, 95% CI 6.3-9.35%). Four tracheal segments were tested for maximal positive intraluminal pressure, which was over 400 mmHg. Degree of rotation testing found that the tracheal segments easily transformed 180° in anterior-posterior bending, lateral bending, and axial rotational twisting. CONCLUSIONS: We define several biomechanical properties of the ex vivo porcine trachea by reporting the rotation, axial stretch capacity, and positive intraluminal pressure capabilities. We hope that this will aid future work in the clinical translation of 3D bioprinted airway replacement grafts and ensure their compatibility with native tracheal properties.

An epigenetic switch regulates the ontogeny of AXL-positive/EGFR-TKi-resistant cells by modulating miR-335 expression.

Despite current advancements in research and therapeutics, lung cancer remains the leading cause of cancer-related mortality worldwide. This is mainly due to the resistance that patients develop against chemotherapeutic agents over the course of treatment. In the context of non-small cell lung cancers (NSCLC) harboring EGFR-oncogenic mutations, augmented levels of AXL and GAS6 have been found to drive resistance to EGFR tyrosine kinase inhibitors such as Erlotinib and Osimertinib in certain tumors with mesenchymal-like features. By studying the ontogeny of AXL-positive cells, we have identified a novel non-genetic mechanism of drug resistance based on cell-state transition. We demonstrate that AXL-positive cells are already present as a subpopulation of cancer cells in Erlotinib-naïve tumors and tumor-derived cell lines and that the expression of AXL is regulated through a stochastic mechanism centered on the epigenetic regulation of miR-335. The existence of a cell-intrinsic program through which AXL-positive/Erlotinib-resistant cells emerge infers the need of treating tumors harboring EGFR-oncogenic mutations upfront with combinatorial treatments targeting both AXL-negative and AXL-positive cancer cells.

Uniportal VATS Lobectomy and Decortication: Not an Everyday Occurrence.

Management of trapped lung with an underlying lung lesion and hydropneumothorax remains controversial. Furthermore, Aspergillus empyema and aspergilloma are rare pathologies for which uniportal video-assisted thoracoscopic (VATS) surgical management remains controversial. We present a young patient referred to our service after recent hospitalization for pneumonia. The patient was found to have a chronic effusion with a right lower lobe cystic parenchymal lesion and was taken to the operating room. The patient underwent right uniportal VATS surgery with evacuation of empyema, total pulmonary decortication, and right lower lobectomy. His postoperative course was unremarkable, and he was discharged home. Postoperative workup demonstrated lymphocyte variant hypereosinophilia. He continues to follow with thoracic surgery at the time of this report and remains asymptomatic. We conclude that uniportal VATS is a most minimally invasive, safe, and efficient approach for management of complex intrathoracic pathology including total pulmonary decortication and lobectomy.

Impact That Day of the Week has on Length of Stay for Video-assisted Lobectomy.

We aimed to analyze the effect that the day of the week for video-assisted thoracoscopic surgery lobectomy has on length of stay . A retrospective review identified all patients who underwent video-assisted thoracoscopic surgery lobectomy at a single institution from January 2016 to July 2017. In total, 208 patients were divided into 2 groups based on timing of their operation: Operations performed on Monday, Tuesday, or Wednesday were defined as "early in the week" and those performed on Thursday or Friday were defined as "late in the week." We then propensity-matched 81 pairs of patients and analyzed perioperative data and short-term clinical outcomes. A total of 208 patients underwent video-assisted thoracic surgery lobectomy during the study period. Length of stay was significantly decreased by 2.0 days (P <0.0001) for all lobectomies performed "early in the week" compared with those performed "late in the week." Thirty-day mortality and all major morbidities did not significantly different between the 2 matched groups. Our findings suggest that major pulmonary resections should be performed early in the week, when feasible, to facilitate utilization of hospital resources and prompt discharge.

Intermediate oncologic outcomes after uniportal video-assisted thoracoscopic thymectomy for early-stage thymoma.

BACKGROUND: Recent years have seen a trend towards utilizing a video-assisted thoracic surgery (VATS) approach for treatment of thymoma. Although increasing in practice, intermediate- and long-term oncologic outcome data is lacking for the VATS approach. There is no oncologic data for the uniportal VATS approach. We sought to evaluate the feasibility and impact on patient survival of uniportal VATS thymectomy for early-stage thymoma. METHOD: The clinical outcomes for 17 patients with Masaoka stage I to II thymomas treated between January of 2009 and July of 2014 at a single institution were collected retrospectively. Primary endpoint was overall survival (OS) and secondary endpoint was recurrence-free survival (RFS). RESULTS: Ten women and seven men underwent uniportal VATS thymectomy; eleven had stage I thymoma and six had stage II thymoma. There were no conversions to open surgery. Operative mortality was zero. Mean tumor size was 3.8±1.0 centimeters, with a range of 1.9 to 6.0 centimeters. All patients underwent a R0 resection. Five-year survival was 100%, and the estimated RFS was 100%. CONCLUSIONS: Our findings suggest that uniportal VATS thymectomy for early-stage thymoma is feasible, and the intermediate-term oncologic outcomes are comparable to historic standards for open and multi-incision VATS thymectomy. However, additional follow-up is required to evaluate for long-term oncologic outcomes.

Robotic-Assisted First Rib Resection: Our Experience and Review of the Literature.

Thoracic outlet syndrome (TOS) comprises a constellation of signs and symptoms that arise from neurologic and vascular compression of the brachial plexus and subclavian vasculature, respectively. Surgical decompression of the neurovascular structures is often indicated to alleviate TOS. We report here our robotic surgical approach and experience for resection of the first rib. Between July 2014 and January 2017, 17 patients who underwent robotic-assisted first rib resection at our institution were reviewed. Nine women and 8 men with a mean age of 45 ± 11 years had a robotic-assisted first rib resection; 8 for neurogenic TOS and 9 for venous TOS. There were no complications or conversion to open surgery. The mean operative time was 113.2 ± 55.3 minutes. Length of stay was a mean of 1.8 ± 1.9 days. Length of rib resected was 5.8 ± 0.5 cm. Anticoagulation for the venous TOS cohort was Xarelto, for a mean of 5.1 ± 1.8 months. Short-term follow-up (mean 10.3 ± 4.9 days) revealed resolution of symptoms in all patients, with patent vasculature on venogram for the entire venous TOS cohort. Further follow-up at 2 months and 6 months revealed that all patients remained symptom free. Based on our institution's experience with the robotic-assisted approach to first rib resection, we feel that it is a feasible approach that could be added to the armamentarium of the thoracic surgeon.

Switching from Thoracoscopic to Robotic Platform for Lobectomy: Report of Learning Curve and Outcome.

OBJECTIVE: The optimal minimally invasive surgical management for patients with non-small-cell lung cancer (NSCLC) is unclear. For experienced video-assisted thoracoscopic surgery (VATS) surgeons, the increased costs and learning curve are strong barriers for adoption of robotics. We examined the learning curve and outcome of an experienced VATS lobectomy surgeon switching to a robotic platform. METHODS: We conducted a retrospective review to identify patients who underwent a robotic or VATS lobectomy for NSCLC from 2016 to 2018. Analysis of patient demographics, perioperative data, pathological upstaging rates, and robotic approach (RA) learning curve was performed. RESULTS: This study evaluated 167 lobectomies in total, 118 by RA and 49 by VATS. Patient and tumor characteristics were similar. RA had significantly more lymph node harvested (14 versus 10; P = 0.004), more nodal stations sampled (5 versus 4; P < 0.001), and more N1 nodes (8 versus 6; P = 0.010) and N2 nodes (6 versus 4; P = 0.017) resected. With RA, 22 patients were upstaged (18.6%) compared to 5 patients (10.2%) with VATS (P = 0.26). No differences were found in perioperative outcome. Operative time decreased significantly with a learning curve of 20 cases, along with a steady increase in lymph node yield. CONCLUSIONS: RA can be adopted safely by experienced VATS surgeons. Learning curve is 20 cases, with RA resulting in superior lymph node clearance compared to VATS. The potential improvement in upstaging and oncologic resection for NSCLC may justify the associated investments of robotics even for experienced VATS surgeons.

A 3-dimensional bioprinted tracheal segment implant pilot study: Rabbit tracheal resection with graft implantation.

OBJECTIVES: Surgical reconstruction of tracheal disease has expanded to include bioengineering and three dimensional (3D) printing. This pilot study investigates the viability of introducing a living functional tracheal replacement graft in a rabbit animal model. METHODS: Seven New Zealand White rabbits were enrolled and six completed participation (one intraoperative mortality). Tracheal replacement grafts were created by impregnating 3D printed biodegradable polycaprolactone (PCL) tracheal scaffolds with rabbit tracheal hyaline chondrocytes. 2 cm of native trachea was resected and the tracheal replacement graft implanted. Subjects were divided into two equal groups (n = 3) that differed in their time of harvest following implantation (three or six weeks). Tracheal specimens were analyzed with intraluminal telescopic visualization and histopathology. RESULTS: The two groups did not significantly differ in histopathology or intraluminal diameter. All sections wherein the implant telescoped over native trachea (anastomotic ends) contained adequate hyaline cartilage formation (i.e. chondrocytes within lacuna, surrounding extracellular matrix, and strong Safranin O staining). Furthermore, the PCL scaffold was surrounded by a thin layer of fibrous tissue. All areas without membranous coverage contained inadequate or immature cartilage formation with inflammation. The average intraluminal stenosis was 83.4% (range 34.2-95%). CONCLUSIONS: We report normal cartilage growth in a tracheal replacement graft when chondrocytes are separated from the tracheal lumen by an intervening membrane. When no such membrane exists there is a propensity for inflammation and stenosis. These findings are important for future construction and implantation of tracheal replacement grafts. LEVEL OF EVIDENCE: Not applicable: this is an in vivo animal trial.

Improving the Odds: Intercostal Metal Coils Mark Area to Resect in Rib Lesions.

Precise localization of a rib lesion for its resection remains a challenge because of multiple factors including nonpalpable pathology, unfavorable body habitus, inaccurate clinical examination, and unreliable rib count on physical examination, unfavorable lesion location within a rib (its posterior aspect), and resection of sclerotic lesions with grossly intact rib cortex. We describe a novel rib localization technique that eliminates potential mistakes and avoids resection of an inappropriate rib. Our method of rib localization includes placement of metallic coils by interventional radiologists under computed tomography guidance where two coils are deployed within the intercostal spaces, one superior and one inferior to the rib lesion. Intraoperative use of fluoroscopy results in precise localization of rib lesions even in cases where the pathology is not grossly apparent. We implemented this approach in 2014 and have since performed it in five patients for both lytic and sclerotic lesions. Placement of markers superficial to the intercostal spaces resulted in their displacement in one case. Successfully, we removed the correct ribs in each patient without technical difficulties or complications. Our series demonstrates a novel strategy for a highly accurate and relatively easy way to identify the exact portion of the rib for surgical resection. Intercostal space positioning of the coil markers superior and inferior to the lesion prevents their dislodgement during patient transport and positioning on the operating room table, which improves rib identification accuracy and reliability. When combined with intraoperative fluoroscopy, it will greatly eliminate resection of incorrect ribs.

Ex vivo tracheomalacia model with 3D-printed external tracheal splint.

OBJECTIVE: To design and evaluate an ex vivo model of tracheomalacia with and without a three-dimensional (3D)-printed external tracheal splint. STUDY DESIGN: Prospective, ex vivo animal trial. METHODS: Three groups of ex vivo porcine tracheas were used: 1) control (unmanipulated trachea), 2) tracheomalacia (tracheal rings partially incised and crushed), and 3) splinted tracheomalacia (external custom tracheal splint fitted onto group 2 trachea). Each end of an ex vivo trachea was sealed with a custom-designed and 3D-printed cap; a transducer was placed through one end to measure the pressure inside the trachea. Although the negative pressure was applied to the tracheal lumen, the tracheal wall collapse was measured externally and internally using a bronchoscope. Each group had at least three recorded trials. Tracheal diameter was evaluated using ImageJ software (National Institutes of Health, Bethesda, MD) and was averaged between two raters. RESULTS: Average tracheal occlusion percentage was compared using Student t test. The average occlusion was 31% for group 1, 87.4% for group 2, and 20% for group 3. Significant differences were found between the control and tracheomalacia groups (P < 0.01) and the tracheomalacia and splinted tracheomalacia groups (P < 0.01). There was no significant difference between the control and splinted tracheomalacia groups (P = 0.13). Applied pressure was plotted against occlusion and regression line slope differed between the tracheomalacia (0.91) and control (0.12) or splinted tracheomalacia (0.39) groups. CONCLUSION: We demonstrate the potential for an ex vivo tracheomalacia model to reproduce airway collapse and show that this collapse can be treated successfully with a 3D-printed external splint. These results are promising and justify further studies. LEVEL OF EVIDENCE: N/A. Laryngoscope, 127:950-955, 2017.

Feasibility of Bioprinting with a Modified Desktop 3D Printer.

Numerous studies have shown the capabilities of three-dimensional (3D) printing for use in the medical industry. At the time of this publication, basic home desktop 3D printer kits can cost as little as $300, whereas medical-specific 3D bioprinters can cost more than $300,000. The purpose of this study is to show how a commercially available desktop 3D printer could be modified to bioprint an engineered poly-l-lactic acid scaffold containing viable chondrocytes in a bioink. Our bioprinter was used to create a living 3D functional tissue-engineered cartilage scaffold. In this article, we detail the design, production, and calibration of this bioprinter. In addition, the bioprinted cells were tested for viability, proliferation, biochemistry, and gene expression; these tests showed that the cells survived the printing process, were able to continue dividing, and produce the extracellular matrix expected of chondrocytes.

Three dimensional printing: A review on the utility within medicine and otolaryngology.

Three dimensional (3D) printing is a novel technique that has evolved over the past 35 years and has the potential to revolutionize the field of medicine with its inherent advantages of customizability and the ability to create complex shapes with precision. It has been used extensively within the fields of orthopedics, dentistry, and craniofacial reconstruction with wide ranging utility including, medical modeling, surgical planning and the production of custom plates, screws and surgical guides. Furthermore, it has been used for similar means in the field of Otorhinolaryngology and also has potential to revolutionize the treatment of airway malacia. In fact, 3D printed external tracheal splints have already been studied in several pediatric patients with very promising results. The emerging field of 3D bioprinting, which integrates tissue engineering with 3D printing, may produce a paradigm shift with the potential introduction of customized functional biologic replacements.

Introducing a 3-dimensionally Printed, Tissue-Engineered Graft for Airway Reconstruction: A Pilot Study.

OBJECTIVE: To use 3-dimensional (3D) printing and tissue engineering to create a graft for laryngotracheal reconstruction (LTR). STUDY DESIGN: In vitro and in vivo pilot animal study. SETTING: Large tertiary care academic medical center. SUBJECTS AND METHODS: A 3D computer model of an anterior LTR graft was designed. That design was printed with polylactic acid on a commercially available 3D printer. The scaffolds were seeded with mature chondrocytes and collagen gel and cultured in vitro for up to 3 weeks. Scaffolds were evaluated in vitro for cell viability and proliferation. Anterior graft LTR was performed on 9 New Zealand white rabbits with the newly created scaffolds. Three animals were sacrificed at each time point (4, 8, and 12 weeks). The in vivo graft sites were assessed via bronchoscopy and histology. RESULTS: The in vitro cell proliferation assay demonstrated initial viability of 87.5%. The cells proliferated during the study period, doubling over the first 7 days. Histology revealed that the cells retained their cartilaginous properties during the 21-day study period. In vivo testing showed that all animals survived for the duration of the study. Bronchoscopy revealed a well-mucosalized tracheal lumen with no evidence of scarring or granulation tissue. Histology indicated the presence of newly formed cartilage in the region where the graft was present. CONCLUSIONS: Our results indicate that it is possible to produce a custom-designed, 3D-printed, tissue-engineered graft for airway reconstruction.

Current readings: Redefining minimally invasive: uniportal video-assisted thoracic surgery.

Minimally invasive surgery is clearly dominating the modern surgical era across multiple surgical subspecialties and thoracic surgery is no exception. Video-assisted thoracic surgery (VATS) is a well-established method of performing various interventions, and it continues to gain momentum. Though small differences in VATS methods exist, it is commonly accepted as a non-rib-spreading approach into the thoracic cavity via 2-4 incisions and allows for a wide range of anatomical and nonanatomical pulmonary resections. As more experience is gained with VATS, more complex surgeries take place and greater refinement of the technique occurs. A newer single-incision or uniportal VATS has been described to minimize surgical trauma, to decrease the number and size of thoracic incisions, to reduce the number of complications, and to enable faster recovery. It allows performing a full spectrum of thoracic operations through a single incision adhering to surgical and oncological principles without compromise.

Complicated pediatric subglottic granular cell tumor with extensive intraluminal and extraluminal invasion.

Subglottic granular cell tumors (GCT) are rare, potentially life threatening benign tumors. Complete resection is necessary, yet care must be taken to preserve laryngeal function. We present the first description of a pediatric subglottic GCT with extensive invasion beyond the confines of the subglottis to include the vocal folds and central neck. Urgent endoscopic debulking avoided tracheotomy and facilitated extubation. Later, complete resection required hemithyroidectomy, laryngofissure and partial cricotracheal resection. We conclude that endoscopic debulking is an appropriate initial treatment. Transmural extension should be suspected in tumors larger than 1cm and warn of the need for tracheal resection.

Pulmonary adenofibroma: cytologic and clinicopathologic features of a rare benign primary lung lesion.

We report a case of pulmonary adenofibroma in a 29-year-old female found by CT scan during work-up for midline chest pain. To our knowledge, the cytological features of this entity have not been previously reported. Cytology demonstrated bland epithelial and stromal cells of varying size without karyorrhexis, pyknosis, or necrosis and with very rare mitoses. Stromal cells were present as either naked bipolar nuclei, as spindle cells with fragile eosinophilic cytoplasm, or as rare larger carrot shaped nuclei. Epithelial cells were present as small loosely cohesive groups with smooth round nuclei and moderate amounts of cytoplasm. Histologically, this lesion consisted of a leaf-like fibroepithelial pattern in which the clefts were lined by a single layer of cuboidal epithelium reminiscent of adenofibroma occurring in the female genital tract. Immunohistochemical analysis demonstrated epithelium that stained positively for pan-cytokeratin and TTF-1. The stroma stained positively for vimentin and desmin, and was weakly positive for SMA-1. The lesion was confirmed to be pulmonary adenofibroma with a smooth muscle component. The differential diagnosis for this lesion includes, but is not limited to, pulmonary hamartoma, pulmonary blastoma, adenomyofibroma, synovial sarcoma, and visceral metastases. It is important for cytopathologists to be aware of this benign entity because it can be encountered on lung FNA specimens. Considering this benign lesion in the differential diagnosis may help plan for minimal lung resection. Confirmatory intraoperative frozen section is a reasonable option.