A pH-Activatable Nanoprobe Labels Diverse Histologic Subtypes of Human Lung Cancer During Resection

BACKGROUND

Intraoperative molecular imaging (IMI) uses tumor-targeted optical contrast agents to improve identification and clearance of cancer during surgery. Recently, pH-activatable contrast agents have been developed but none has been tested in lung cancer. Here, we report the successful clinical translation of pegsitacianine (ONM-100), a pH-activatable nanoprobe, for fluorescence-guided lung cancer resection.

METHODS

We first characterized the pH setpoint for pegsitacianine fluorescence activation in vitro. We then optimized the specificity, dosing, and timing of pegsitacianine in murine flank xenograft models of lung adenocarcinoma and squamous cell carcinoma. Finally, we tested pegsitacianine in humans undergoing lung cancer surgery as part of an ongoing phase 2 trial.

RESULTS

We found that the fluorescence activation of pegsitacianine occurred below physiologic pH in vitro. Using preclinical models of lung cancer, we found that the probe selectively labeled both adenocarcinoma and squamous cell carcinoma xenografts (mean tumor-to-background ratio [TBR] > 2.0 for all cell lines). In the human pilot study, we report cases in which pegsitacianine localized pulmonary adenocarcinoma and pulmonary squamous cell carcinoma (TBRs= 2.7 and 2.4) in real time to illustrate its successful clinical translation and potential to improve surgical management.

CONCLUSIONS

This translational study demonstrates the feasibility of pegsitacianine as an IMI probe to label the two most common histologic subtypes of human lung cancer.

Three-Dimensional Near-Infrared Specimen Mapping Can Identify the Distance from the Tumor to the Surgical Margin During Resection of Pulmonary Ground Glass Opacities

BACKGROUND

Lung cancers can recur locally due to inadequate resection margins. Achieving adequate margin distances is challenging in pulmonary ground glass opacities (GGOs) because they are not easily palpable. To improve margin assessment during resection of GGOs, we propose a novel technique, three-dimensional near-infrared specimen mapping (3D-NSM).

METHODS

Twenty patients with a cT1 GGO were enrolled and received a fluorescent tracer preoperatively. After resection, specimens underwent 3D-NSM in the operating room. Margins were graded as positive or negative based upon fluorescence at the staple line. Images were analyzed using ImageJ to quantify the distance from the tumor edge to the nearest staple line. This margin distance calculated by 3D-NSM was compared to the margin distance reported on final pathology several days postoperatively.

RESULTS

3D-NSM identified 20/20 GGOs with no false positive or false negative diagnoses. Mean fluorescence intensity for lesions was 110.92 arbitrary units (A.U.) (IQR: 77.77-122.03 A.U.) compared to 23.68 A.U. (IQR: 19.60-27.06 A.U.) for background lung parenchyma (p < 0.0001). There were 4 tumor-positive or close margins in the study cohort, and all 4 (100%) were identified by 3D-NSM. 3D-NSM margin distances were nearly identical to margin distances reported on final pathology (R2 = 0.9362). 3D-NSM slightly under-predicted margin distance, and the median difference in margins was 1.9 mm (IQR 0.5-4.3 mm).

CONCLUSIONS

3D-NSM rapidly localizes GGOs by fluorescence and detects tumor-positive or close surgical margins. 3D-NSM can accurately quantify the resection margin distance as compared to formal pathology, which allows surgeons to rapidly determine whether sublobar resection margin distances are adequate.

Single-institution experience of 500 pulmonary resections guided by intraoperative molecular imaging

OBJECTIVE

Intraoperative molecular imaging (IMI) using tumor-targeted optical contrast agents can improve thoracic cancer resections. There are no large-scale studies to guide surgeons in patient selection or imaging agent choice. Here, we report our institutional experience with IMI for lung and pleural tumor resection in 500 patients over a decade.

METHODS

Between December 2011 and November 2021, patients with lung or pleural nodules undergoing resection were preoperatively infused with 1 of 4 optical contrast tracers: EC17, TumorGlow, pafolacianine, or SGM-101. Then, during resection, IMI was used to identify pulmonary nodules, confirm margins, and identify synchronous lesions. We retrospectively reviewed patient demographic data, lesion diagnoses, and IMI tumor-to-background ratios (TBRs).

RESULTS

Five hundred patients underwent resection of 677 lesions. We found that there were 4 types of clinical utility of IMI: detection of positive margins (n = 32, 6.4% of patients), identification of residual disease after resection (n = 37, 7.4%), detection of synchronous cancers not predicted on preoperative imaging (n = 26, 5.2%), and minimally invasive localization of nonpalpable lesions (n = 101 lesions, 14.9%). Pafolacianine was most effective for adenocarcinoma-spectrum malignancies (mean TBR, 2.84), and TumorGlow was most effective for metastatic disease and mesothelioma (TBR, 3.1). False-negative fluorescence was primarily seen in mucinous adenocarcinomas (mean TBR, 1.8), heavy smokers (>30 pack years; TBR, 1.9), and tumors greater than 2.0 cm from the pleural surface (TBR, 1.3).

CONCLUSIONS

IMI may be effective in improving resection of lung and pleural tumors. The choice of IMI tracer should vary by the surgical indication and the primary clinical challenge.

Comparative Experience of Short-wavelength Versus Long-wavelength Fluorophores for Intraoperative Molecular Imaging of Lung Cancer

BACKGROUND

Intraoperative molecular imaging (IMI) using tumor-targeted optical contrast agents can improve cancer resections. The optimal wavelength of the IMI tracer fluorophore has never been studied in humans and has major implications for the field. To address this question, we investigated 2 spectroscopically distinct fluorophores conjugated to the same targeting ligand.

METHODS

Between December 2011 and November 2021, patients with primary lung cancer were preoperatively infused with 1 of 2 folate receptor-targeted contrast tracers: a short-wavelength folate-fluorescein (EC17; λ em =520 nm) or a long-wavelength folate-S0456 (pafolacianine; λ em =793 nm). During resection, IMI was utilized to identify pulmonary nodules and confirm margins. Demographic data, lesion diagnoses, and fluorescence data were collected prospectively.

RESULTS

Two hundred eighty-two patients underwent resection of primary lung cancers with either folate-fluorescein (n=71, 25.2%) or pafolacianine (n=211, 74.8%). Most tumors (n=208, 73.8%) were invasive adenocarcinomas. We identified 2 clinical applications of IMI: localization of nonpalpable lesions (n=39 lesions, 13.8%) and detection of positive margins (n=11, 3.9%). In each application, the long-wavelength tracer was superior to the short-wavelength tracer regarding depth of penetration, signal-to-background ratio, and frequency of event. Pafolacianine was more effective for detecting subpleural lesions (mean signal-to-background ratio=2.71 vs 1.73 for folate-fluorescein, P <0.0001). Limit of signal detection was 1.8 cm from the pleural surface for pafolacianine and 0.3 cm for folate-fluorescein.

CONCLUSIONS

Long-wavelength near-infrared fluorophores are superior to short-wavelength IMI fluorophores in human tissues. Therefore, future efforts in all human cancers should likely focus on long-wavelength agents.

A Cathepsin-Targeted Quenched Activity-Based Probe Facilitates Enhanced Detection of Human Tumors during Resection

PURPOSE

Fluorescence-guided surgery using tumor-targeted contrast agents has been developed to improve the completeness of oncologic resections. Quenched activity-based probes that fluoresce after covalently binding to tumor-specific enzymes have been proposed to improve specificity, but none have been tested in humans. Here, we report the successful clinical translation of a cathepsin activity-based probe (VGT-309) for fluorescence-guided surgery.

EXPERIMENTAL DESIGN

We optimized the specificity, dosing, and timing of VGT-309 in preclinical models of lung cancer. To evaluate clinical feasibility, we conducted a canine study of VGT-309 during pulmonary tumor resection. We then conducted a randomized, double-blind, dose-escalation study in healthy human volunteers receiving VGT-309 to evaluate safety. Finally, we tested VGT-309 in humans undergoing lung cancer surgery.

RESULTS

In preclinical models, we found highly specific tumor cell labeling that was blocked by a broad spectrum cathepsin inhibitor. When evaluating VGT-309 for guidance during resection of canine tumors, we found that the probe selectively labeled tumors and demonstrated high tumor-to-background ratio (TBR; range: 2.15-3.71). In the Phase I human study, we found that VGT-309 was safe at all doses studied. In the ongoing Phase II trial, we report two cases in which VGT-309 localized visually occult, non-palpable tumors (TBRs = 2.83 and 7.18) in real time to illustrate its successful clinical translation and potential to improve surgical management.

CONCLUSIONS

This first-in-human study demonstrates the safety and feasibility of VGT-309 to label human pulmonary tumors during resection. These results may be generalizable to other cancers due to cathepsin overexpression in many solid tumors.

First-in-human results of targeted intraoperative molecular imaging for visualization of ground glass opacities during robotic pulmonary resection

Background

Identifying ground glass opacities (GGOs) is challenging during robot-assisted thoracic surgery (RATS). Intraoperative molecular imaging (IMI) using tumor-targeted fluorescent tracers may address this clinical problem, but has never been evaluated in RATS. In a pilot study, we sought to determine whether IMI during RATS (RIMI) can localize GGOs.

Methods

Ten patients with a cT1 GGO were enrolled. Prior to resection, participants received a folate-receptor targeted fluorescent tracer (OTL38). During RATS, a white-light robotic scope was utilized to identify tumors. RIMI was then conducted using a RATS thoracoscope with a wavelength-specific camera. Finally, a video-assisted thoracic surgery (VATS) thoracoscope designed to detect OTL38 was used as a control to compare to RIMI. The lesions were then resected under RIMI guidance.

Results

By white-light robotic scope, 7/10 (70%) GGOs were visually identifiable by pleuroparenchymal distortions. RIMI identified tumor-specific fluorescence in all (100%) subjects. RIMI clearly located the three nodules that could not be seen by robotic white-light imaging. The mean fluorescence intensity (MFI) of tumors was 99.48 arbitrary units (A.U.) (IQR, 75.72–130.49 A.U.), which was significantly higher than background tissue with mean MFI 20.61 A.U. (IQR, 13.49–29.93 A.U., P<0.0001). Mean signal-to-background ratio was 5.71 (range, 2.28–10.13). When compared to VATS-IMI as a control, there were no significant differences in MFI of tumors, background tissue, or signal-to-background ratios. In summary, RIMI compared favorably to VATS-IMI by all measured imaging characteristics.

Conclusions

RIMI is feasible for identification of GGOs during robotic resection as compared to white light thoracoscopy and compares favorably to VATS-IMI.

Targeted detection of cancer cells during biopsy allows real-time diagnosis of pulmonary nodules

Background

The diagnostic yield of biopsies of solitary pulmonary nodules (SPNs) is low, particularly in sub-solid lesions. We developed a method (NIR-nCLE) to achieve cellular level cancer detection during biopsy by integrating (i) near-infrared (NIR) imaging using a cancer-targeted tracer (pafolacianine), and (ii) a flexible NIR confocal laser endomicroscopy (CLE) system that can fit within a biopsy needle. Our goal was to assess the diagnostic accuracy of NIR-nCLE ex vivo in SPNs.

Methods

Twenty patients with SPNs were preoperatively infused with pafolacianine. Following resection, specimens were inspected to identify the lesion of interest. NIR-nCLE imaging followed by tissue biopsy was performed within the lesion and in normal lung tissue. All imaging sequences (n = 115) were scored by 5 blinded raters on the presence of fluorescent cancer cells and compared to diagnoses by a thoracic pathologist.

Results

Most lesions (n = 15, 71%) were adenocarcinoma-spectrum malignancies, including 7 ground glass opacities (33%). Mean fluorescence intensity (MFI) by NIR-nCLE for tumor biopsy was 20.6 arbitrary units (A.U.) and mean MFI for normal lung was 6.4 A.U. (p < 0.001). Receiver operating characteristic analysis yielded a high area under the curve for MFI (AUC = 0.951). Blinded raters scored the NIR-nCLE sequences on the presence of fluorescent cancer cells with sensitivity and specificity of 98% and 97%, respectively. Overall diagnostic accuracy was 97%. The inter-observer agreement of the five raters was excellent (κ = 0.95).

Conclusions

NIR-nCLE allows sensitive and specific detection of cancer cells in SPNs. This technology has far-reaching implications for diagnostic needle biopsies and intraprocedural decision-making.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-022-05868-9.

Targeted detection of cancer at the cellular level during biopsy by near-infrared confocal laser endomicroscopy

Suspicious nodules detected by radiography are often investigated by biopsy, but the diagnostic yield of biopsies of small nodules is poor. Here we report a method-NIR-nCLE-to detect cancer at the cellular level in real-time during biopsy. This technology integrates a cancer-targeted near-infrared (NIR) tracer with a needle-based confocal laser endomicroscopy (nCLE) system modified to detect NIR signal. We develop and test NIR-nCLE in preclinical models of pulmonary nodule biopsy including human specimens. We find that the technology has the resolution to identify a single cancer cell among normal fibroblast cells when co-cultured at a ratio of 1:1000, and can detect cancer cells in human tumors less than 2 cm in diameter. The NIR-nCLE technology rapidly delivers images that permit accurate discrimination between tumor and normal tissue by non-experts. This proof-of-concept study analyzes pulmonary nodules as a test case, but the results may be generalizable to other malignancies.

A Prostate-Specific Membrane Antigen-Targeted Near-Infrared Conjugate for Identifying Pulmonary Squamous Cell Carcinoma during Resection

Pulmonary squamous cell carcinoma is the second most common lung cancer subtype and has a low 5-year survival rate at 17.6%. Complete resection with negative margins can be curative, but a high number of patients suffer early postoperative recurrence due to inadequate disease clearance at the index operation. Intraoperative molecular imaging (IMI) with tumor-targeted optical contrast agents is effective in improving resection completeness for other tumor types, but there are no IMI tracers targeted to pulmonary squamous cell carcinoma. In this report, we describe the use of a novel prostate-specific membrane antigen (PSMA)-targeted near-infrared conjugate (OTL78) to identify pulmonary squamous cell carcinoma. We identified PSMA as a viable target by examining its expression in human lung tumor specimens from a surgical cohort. Ninety-four percent of tumors expressed PSMA in either the pulmonary squamous cells or the tumor neovasculature. Using in vitro and in vivo models, we found that OTL78 reliably localized pulmonary squamous cell carcinoma in a PSMA-dependent manner. Finally, we found that IMI with OTL78 markedly improved surgeons' ability to identify residual disease after surgery in a preclinical model. Ultimately, this novel optical tracer may aid surgical resection of pulmonary squamous cell carcinoma and potentially improve long-term outcomes.

Pericardial–Esophageal Fistula: A Rare but Increasing Complication of Cardiac Ablation

Pericardial–esophageal fistula and/or atrial–esophageal fistula after cardiac ablation is nearly universally fatal if not detected and treated expeditiously. This condition should be assumed and ruled out in anyone with a recent history of cardiac ablation presenting with signs of sepsis, pneumomediastinum, pneumopericardium, or chest pain. Computed tomography scan of the chest is a rapid and a sensitive diagnostic modality. Tenets of treatment and repair consist of preventing an air embolism, repairing the esophageal perforation and atrial defect, and interposing autologous tissue between the esophagus and heart.

3D Specimen Mapping Expedites Frozen Section Diagnosis of Non-Palpable Ground Glass Opacities

BACKGROUND

Pulmonary ground glass opacities (GGOs) are early-stage adenocarcinoma spectrum lesions that are not easily palpable. Challenges in localizing GGOs during intraoperative pathology can lead to imprecise diagnoses and additional time under anesthesia. To improve localization of GGOs during frozen section diagnosis, we evaluated a novel technique, three-dimensional near-infrared specimen mapping (3D-NSM).

METHODS

Fifty-five patients with a cT1 GGO were enrolled and received a fluorescent tracer preoperatively. After resection, specimens were inspected to identify lesions. Palpable and non-palpable nodules underwent 3D-NSM and the area of highest fluorescence was marked with a suture. Time for 3D-NSM, time for frozen section diagnosis, and number of tissue sections examined were recorded. To compare 3D-NSM to standard-of-care techniques, a control cohort of twenty subjects with identical inclusion criteria were enrolled. Specimens did not undergo 3D-NSM and were sent directly to pathology.

RESULTS

3D-NSM localized 54/55 lesions with one false negative. All 41 palpable lesions were identified by 3D-NSM. Thirteen of 14 non-palpable lesions (92.8%) were located by 3D-NSM. Time to diagnosis for the 3D-NSM cohort was 23.5 minutes, compared to 26.0 minutes in the control cohort (p=0.04). 3D-NSM did not affect time to diagnosis of palpable lesions (23.2 min vs. 21.4 minutes, p=0.10). 3D-NSM significantly reduced time to diagnosis for non-palpable lesions (t=23.3 min vs. 34.4 minutes, p<0.0001). 3D-NSM also reduced the number of tissue sections analyzed in non-palpable lesions (4.50 vs. 11.00, p<0.0001).

CONCLUSIONS

3D-NSM accurately localizes GGOs and expedites intraoperative diagnosis by reducing the number of tissue sections analyzed for non-palpable GGOs.

Targeted Intraoperative Molecular Imaging for Localizing Nonpalpable Tumors and Quantifying Resection Margin Distances

Importance

Complete (R0) resection is the dominant prognostic factor for survival across solid tumor types. Achieving adequate tumor clearance with appropriate margins is particularly difficult in nonpalpable tumors or in situ disease. Previous methods to address this problem have proven time consumptive, impractical, or ineffective.

Objective

To assess the capability of intraoperative molecular imaging (IMI), a novel technology using a fluorescent tracer targeted to malignant cells, to localize visually occult, nonpalpable tumors and quantify margin distances during resection.

Design, Setting, and Participants

This nonrandomized open-label trial of IMI using a folate receptor-targeted fluorescent tracer enrolled patients between May 2017 and June 2020 at a single referral center. Eligible patients included those with a small (T1) lung lesion suspicious for malignant neoplasms and with radiographic features suggestive of a nonpalpable lesion.

Interventions

Patients were preoperatively infused with a folate receptor-targeted near-infrared tracer. Intraoperatively, surgeons used thoracoscopic visualization and palpation to identify lesions. IMI was performed to detect the lesion in situ, and lesions were imaged ex vivo. Margins were assessed by IMI before comparison with those reported on final histopathologic analysis.

Main Outcomes and Measures

The main outcomes were whether IMI could (1) localize nonpalpable lung lesions in situ and (2) quantify margin distance with comparison with final pathology as the criterion standard. Patient demographic information and lesion characteristics were prospectively recorded.

Results

Of 40 patients, 26 (65%) were female, and the median (interquartile range) age was 66.5 (62-72) years. Conventional surgical methods localized 22 of 40 lesions (55%), while IMI localized 36 of 40 (90%). Of 18 nonpalpable lesions, 15 (83.3%) were identified by IMI. Both palpable and nonpalpable lesions demonstrated mean signal-to-background ratio more than 2. An IMI margin was able to be calculated for 39 of 40 patients (95%). IMI margins were nearly identical to margins reported on final pathology (R2 = 0.9593), with median (interquartile range) difference of 1.3 (0.7-2.0) mm. IMI detected 2 margins in nonpalpable tumors that were clinically unacceptable and would have had a high probability of recurrence.

Conclusions and Relevance

To our knowledge, this study presents the first clinical use of IMI for nonpalpable tumors and provides proof of principle for the utility of IMI across the field of surgical oncology in identifying occult disease and tumor-positive margins.

The efficacy and safety of definitive concurrent chemoradiotherapy for non-operable esophageal cancer

Objective

To report outcomes and toxicity in patients who received definitive concurrent chemoradiation (DCCRT) for non‐operable esophageal cancer (EC) in the modern era, and to identify markers of overall and disease‐free survival (OS/DFS).

Methods

We conducted a retrospective cohort study of patients with unresectable EC who received DCCRT at our institution between 1/2008 and 1/2019. Descriptive statistics were used to report disease‐control outcomes and CTCAE v4.0–5.0 toxicities. Univariable and multivariable Cox regression, and stepwise regression were used to identify associations with survival.

Results

At a median follow‐up of 19.5 months, 130 patients with adenocarcinoma (AC) (62%) or squamous cell carcinoma (SCC) (38%) were evaluable (Stage II‐III: 92%). Patients received carboplatin/paclitaxel (75%) or fluorouracil‐based (25%) concurrent chemotherapy. Median total RT dose was 50.4 Gy (range, 44.7–71.4 Gy) delivered in 28 fractions (24–35). Locoregional and distant recurrence occurred in 30% and 35% of AC, and 24% and 33% of SCC, respectively. Median OS and DFS were 22.9 and 10.7 months in AC, and 25.7 and 20.2 months in SCC, respectively. On stepwise regression, tumor stage, feeding tube during DCCRT, and change in primary tumor PET/CT SUVmax were significantly associated with OS and DFS. Most severe toxicities were acute grade 4 hematologic cytopenia (6%) and radiation dermatitis (1%). Most common acute grade 3 toxicities were hematologic cytopenia (35%), dysphagia (23%), and anorexia (19%).

Conclusions

Treatment of non‐operable EC with DCCRT has acceptable toxicity and can provide multi‐year disease control for some patients, even in AC. Continued follow‐up and investigation in large studies would be useful.

Management of Lung Cancer During the COVID-19 Pandemic

Coronavirus disease 2019 (COVID-19) has had a devastating impact around the world. With high rates of transmission and no curative therapies or vaccine yet available, the current cornerstone of management focuses on prevention by social distancing. This includes decreased health care contact for patients. Patients with lung cancer are a particularly vulnerable population, where the risk of mortality from cancer must now be balanced by the potential risk of a life-threatening infection. In these unprecedented times, a collaborative and multidisciplinary approach is required to streamline but not compromise care. We have developed guidelines at our academic cancer center to standardize management of patients with lung cancer across our health care system and provide guidance to the larger oncology community. We recommend that general principles of lung cancer treatment continue to be followed in most cases where delays could result in rapid cancer progression. We recognize that our recommendations may change over time based on clinical resources and the evolving nature of the COVID-19 pandemic. In principle, however, treatment paradigms must continue to be individualized, with careful consideration of risks and benefits of continuing or altering lung cancer-directed therapy.

A clinical trial of intraoperative near-infrared imaging to assess tumor extent and identify residual disease during anterior mediastinal tumor resection

BACKGROUND

The management of most solid tumors of the anterior mediastinum involves complete resection. Because of their location near mediastinal structures, wide resection is not possible; therefore, surgeons must use subjective visual and tactile cues to determine disease extent. This clinical trial explored intraoperative near-infrared (NIR) imaging as an approach to improving tumor delineation during mediastinal tumor resection.

METHODS

Twenty-five subjects with anterior mediastinal lesions suspicious for malignancy were enrolled in an open-label feasibility trial. Subjects were administered indocyanine green (ICG) at a dose of 5 mg/kg, 24 hours before resection (via a technique called TumorGlow). The NIR imaging systems included Artemis (Quest, Middenmeer, the Netherlands) and Iridium (VisionSense Corp, Philadelphia, Pennsylvania). Intratumoral ICG uptake was evaluated. The clinical value was determined via an assessment of the ability of NIR imaging to detect phrenic nerve involvement or incomplete resection. Clinical and histopathologic variables were analyzed to determine predictors of tumor fluorescence.

RESULTS

No drug-related toxicity was observed. Optical imaging added a mean of 10 minutes to case duration. Among the subjects with solid tumors, 19 of 20 accumulated ICG. Fluorescent tumors included thymomas (n = 13), thymic carcinomas (n = 4), and liposarcomas (n = 2). NIR feedback improved phrenic nerve dissection (n = 4) and identified residual disease (n = 2). There were no false-positives or false-negatives. ICG preferentially accumulated in solid tumors; this was independent of clinical and pathologic variables.

CONCLUSIONS

NIR imaging for anterior mediastinal neoplasms is safe and feasible. This technology may provide a real-time tool capable of determining tumor extent and specifically identify phrenic nerve involvement and residual disease.

Near-infrared intraoperative imaging for minimally invasive pulmonary metastasectomy for sarcomas

BACKGROUND

Complete pulmonary metastasectomy for sarcoma metastases provides patients an opportunity for long-term survival and possible cure. Intraoperative localization of preoperatively identified metastases and identification of occult lesions can be challenging. In this trial, we evaluated the efficacy of near-infrared (NIR) intraoperative imaging using second window indocyanine green during metastasectomy to identify known metastases and to detect occult nodules.

METHODS

Thirty patients with pulmonary nodules suspicious for sarcoma metastases were enrolled in an open-label, feasibility study (NCT02280954). All patients received intravenous indocyanine green (5 mg/kg) 24 hours before metastasectomy. Patients 1 through 10 (cohort 1) underwent metastasectomy via thoracotomy to assess fluorescence patterns of nodules detected by traditional methods (preoperative imaging and intraoperative visualization/bimanual palpation). After confirming reliability within cohort 1, patients 11 through 30 (cohort 2) underwent video-assisted thoracic surgery metastasectomy with NIR imaging.

RESULTS

In cohort 1, 14 out of 16 preoperatively identified pulmonary metastases (87.5%) displayed tumor fluorescence. Nonfluorescent metastases were deeper than fluorescent metastases (2.1 cm vs 1.3 cm; P = .03). Five out of 5 metastases identified during thoracotomy displayed fluorescence. NIR imaging identified 3 additional occult lesions in this cohort. In cohort 2, 33 out of 37 known pulmonary metastases (89.1%) displayed fluorescence. Nonfluorescent tumors were deeper than 2.0 cm (P = .007). NIR imaging identified 24 additional occult lesions. Of 24 occult lesions, 21 (87.5%) were confirmed metastases and the remaining 3 nodules were lymphoid aggregates.

CONCLUSIONS

NIR intraoperative imaging with indocyanine green (5 mg/kg and 24 hours before surgery) localizes known sarcoma pulmonary metastases and identifies otherwise occult lesions. This approach may be a useful intraoperative adjunct to improve metastasectomy.

Implications of Hospital Volume on Costs Following Esophagectomy in the United States

BACKGROUND

With increasing focus on health care quality and cost containment, volume-based referral strategies have been proposed to improve value in high-cost procedures, such as esophagectomy. While the effect of hospital volume on outcomes has been demonstrated, our goal was to evaluate the economic consequences of volume-based referral practices for esophagectomy.

METHODS

The nationwide inpatient sample (NIS) was queried for the years 2004-2013 for all patients undergoing esophagectomy. Patients were stratified by hospital volume quartile and substratified by preoperative risk and age. Clustered multivariable hierarchical logistic regression analysis was used to assess adjusted costs and mortality.

RESULTS

In total, 9270 patients were clustered based on annual hospital volume quartiles of < 7, 7 to 22, 23 to 87, and > 87 esophagectomies. After stratification by patient variables, high-volume centers performed esophagectomies in high-risk patients at the same cost as low-volume centers without significant difference in resource utilization. Overall, mortality decreased across volume quartiles (lowest 8.9 versus highest 3.6%, p < 0.0001). The greatest volume-mortality differences were observed among patients aged between 70 and 80 years (lowest 12.2 versus highest 6.2%, p = 0.009). Patients with high preoperative risk also derived mortality benefits with increasing hospital volume (lowest 17.5 versus highest 11.8%, p < 0.0001).

CONCLUSIONS

This study demonstrates that the mortality improvements for high-risk patients undergoing esophagectomy at high-volume centers do not come at increased costs. These results suggest that health systems should consider selectively referring high-risk patients to high-volume centers within their region.

A Clinical Trial of TumorGlow to Identify Residual Disease During Pleurectomy and Decortication

BACKGROUND

Macroscopic complete resection can improve survival in a select group of patients with malignant pleural mesothelioma. During resection, differentiating residual tumor from inflammation or scar can be challenging. This trial evaluated near-infrared (NIR) intraoperative imaging using TumorGlow (a novel NIR imaging approach utilizing high-dose indocyanine green and delayed imaging) technology to improve detection of macroscopic residual disease.

METHODS

Twenty subjects were enrolled in an open-label clinical trial of NIR intraoperative imaging with TumorGlow (Indocyanine Green for Solid Tumors [NCT02280954]). Twenty-four hours before pleural biopsy or pleurectomy and decortication (P/D), patients received intravenous indocyanine green. All specimens identified during standard-of-care surgical resection and with NIR imaging underwent histopathologic profiling and correlative microscopic fluorescent tomographic evaluation. For subjects undergoing P/D (n = 13), the hemithorax was evaluated with NIR imaging during P/D to assess for residual disease. When possible, additional fluorescent lesions were resected.

RESULTS

Of 203 resected specimens submitted for evaluation, indocyanine green accumulated within 113 of 113 of resected mesothelioma specimens, with a mean signal-to-background fluorescence ratio of 3.1 (SD, 2.2 to 4.8). The mean signal-to-background fluorescence ratio of benign tissues was 2.2 (SD, 1.4 to 2.4), which was significantly lower than in malignant specimens (p = 0.001). NIR imaging identified occult macroscopic residual disease in 10 of 13 subjects. A median of 5.6 resectable residual deposits per patient (range, 0 to 11 deposits per patient), with a mean size of 0.3 cm (range, 0.1 to 1.5 cm), were identified.

CONCLUSIONS

TumorGlow for malignant pleural mesothelioma is safe and feasible. Excellent sensitivity allows for to reliable detection of macroscopic residual disease during cytoreductive surgical procedures.

Localization of Pulmonary Ground-Glass Opacities with Folate Receptor-Targeted Intraoperative Molecular Imaging

PURPOSE

Intraoperative localization and resection of ill-defined pulmonary ground-glass opacities (GGOs) during minimally invasive pulmonary resection is technically challenging. Current preoperative techniques to facilitate localization of GGOs include microcoil and hook wire placement, both of which have logistic limitations, carry safety concerns, and do not help with margin assessment. In this clinical trial, we explored an alternative method involving near-infrared molecular imaging with a folate receptor-targeted agent, OTL38, to improve localization of GGOs and confirmation of resection margins.

METHODS

In a human trial, 20 subjects with pulmonary GGOs who were eligible for video-assisted thoracoscopic surgery (VATS) resection received 0.025 mg/kg of OTL38 before the resection. The primary objectives were to (1) determine whether use of OTL38 allows safe localization of GGOs and assessment of margins during VATS and (2) determine patient, radiographic, and histopathologic variables that predict the amount of fluorescence during near-infrared imaging.

RESULTS

We observed no toxicity. Of the 21 GGOs, 20 accumulated OTL38 and displayed fluorescence upon in situ or back table evaluation. Intraoperatively, near-infrared imaging localized 15 of 21 lesions whereas VATS alone localized 10 of 21 (p = 0.05). The addition of molecular imaging affected care of nine of 21 subjects by improving intraoperative localization (n = 6) and identifying close margins (n = 3). This approach was most effective for subpleural lesions measuring less than 2 cm. For lesions deeper than 1.5 cm from the pleural surface, intraoperative localization using fluorescent feedback was limited.

CONCLUSIONS

This approach provides a safe alternative for intraoperative localization of small, peripherally located pulmonary lesions. In contrast to alternative localization techniques, use of OTL38 also allows confirmation of adequate margins. Future studies will compare this approach to alternative localization techniques in a clinical trial.

ROS1 Rearrangement in a Case of Classic Biphasic Pulmonary Blastoma

Classic biphasic pulmonary blastoma (CBPB) is a rare and aggressive type of non-small cell lung carcinoma (NSCLC) presenting in adults in the fourth to fifth decade. The prognosis is poor and after surgical resection, therapeutic options are often limited. ROS1 is a proto-oncogene receptor tyrosine kinase that has been identified in some types of NSCLC. We report a case of a 36-year-old woman with CBPB, which was subsequently found to have a ROS1 rearrangement. This is the first reported case of a ROS1-rearranged CBPB. This finding has therapeutic implications as these tumors have the potential to be treated with receptor tyrosine kinase inhibitors.

Surgical Management of Early-Stage Esophageal Adenocarcinoma Based on Lymph Node Metastasis Risk

BACKGROUND

In early-stage esophageal adenocarcinoma (EAC), esophagectomy improves staging but also increases mortality compared with endoscopic resection. Our objective was to quantify esophagectomy mortality and lymph node metastasis (LNM) risk in early-stage EAC to improve surgical treatment allocation.

METHODS

We identified National Cancer Database (2004-2014) patients with nonmetastatic, Tis, T1a, or T1b EAC who had primary surgical resection and microscopic examination of at least 15 lymph nodes. Univariate and multivariable logistic regression identified predictors of LNM. Cox regression identified predictors of death. The Kaplan-Meier method predicted overall survival (OS).

RESULTS

In 782 patients, LNM rates were: all patients 13.8%, Tis 0%, T1a 3.6%, T1b 23.4%. Independent predictors of LNM were submucosal invasion, lymphovascular invasion (LVI), decreasing differentiation, and tumor size ≥ 2 cm (P < 0.05). For T1a tumors with poor differentiation or size ≥ 2 cm, LNM rates were 10.2 and 6.7%, respectively; 90-day mortality was 3.1%. The LNM rate in well differentiated T1b tumors < 2 cm was 4.2%; 90-day mortality was 6.0%. Estimated 5-year OS was 80.2% versus 64.4% (T1a vs. T1b). LNM increased risk of death for T1a (hazard ratio [HR] 8.52, 95% confidence interval [CI] 3.13-23.22, P < 0.001) and T1b tumors (HR 2.52, 95% CI 1.59-4.00, P < 0.001).

CONCLUSIONS

In T1a EAC with poor differentiation or size ≥ 2 cm, esophagectomy should be considered, whereas in T1b EAC with low-risk features (well-differentiated T1b EAC < 2 cm without LVI), endoscopic resection may be sufficient. Treatment guidelines for early-stage EAC should include all high-risk tumor features for LNM and stage-specific esophagectomy mortality.

Intraoperative Molecular Imaging Combined With Positron Emission Tomography Improves Surgical Management of Peripheral Malignant Pulmonary Nodules

OBJECTIVE

To determine if intraoperative molecular imaging (IMI) can improve detection of malignant pulmonary nodules.

BACKGROUND

18-Fluorodeoxyglucose positron emission tomography (PET) is commonly utilized in preoperative assessment of patients with solid malignancies; however, false negatives and false positives remain major limitations. Using patients with pulmonary nodules as a study model, we hypothesized that IMI with a folate receptor targeted near-infrared contrast agent (OTL38) can improve malignant pulmonary nodule identification when combined with PET.

METHODS

Fifty patients with pulmonary nodules with imaging features suspicious for malignancy underwent preoperative PET. Patients then received OTL38 before pulmonary resection. During resection, IMI was utilized to evaluate known pulmonary nodules and identify synchronous lesions. Tumor size, PET standardized uptake value, and IMI tumor-to-background ratios were compared for known and synchronous nodules via paired and unpaired t tests, when appropriate. Test characteristics of PET and IMI with OTL38 were compared.

RESULTS

IMI identified 56 of 59 (94.9%) malignant pulmonary nodules identified by preoperative imaging. IMI located an additional 9 malignant lesions not identified preoperatively. Nodules only detected by IMI were smaller than nodules detected preoperatively (0.5 vs 2.4 cm; P < 0.01), but displayed similar fluorescence (tumor-to-background ratio 3.3 and 3.1; P = 0.50). Sensitivity of IMI and PET were 95.6% and 73.5% (P = 0.001), respectively; and positive predictive values were 94.2% and 89.3%, respectively (P > 0.05). Additionally, utilization of IMI clinically upstaged 6 (12%) subjects and improved management of 15 (30%) subjects.

CONCLUSIONS

These data suggest that combining IMI with PET may provide superior oncologic outcomes for patients with resectable lung cancer.

Intraoperative imaging identifies thymoma margins following neoadjuvant chemotherapy

Near infrared (NIR) molecular imaging is useful to identify tumor margins during surgery; however, the value of this technology has not been evaluated for tumors that have been pre-treated with chemotherapy. We hypothesized that NIR molecular imaging could locate mediastinal tumor margins in a murine model after neoadjuvant chemotherapy. Flank thymomas were established on mice. Two separate experiments were performed for tumor margin detection. The first experiment compared (i) surgery and (ii) surgery + NIR imaging. The second experiment compared (iii) preoperative chemotherapy + surgery, and (iv) preoperative chemotherapy + surgery + NIR imaging. NIR imaging occurred following systemic injection of indocyanine green. Margins were assessed for residual tumor cells by pathology. NIR imaging was superior at detecting retained tumor cells during surgery compared to standard techniques (surgery alone vs. surgery + NIR imaging, 20% vs. 80%, respectively). Following chemotherapy, the sensitivity of NIR imaging of tumor margins was not significantly altered. The mean in vivo tumor-to-background fluorescence ratio was similar in the treatment-naïve and chemotherapy groups ((p = 0.899): 3.79 ± 0.69 (IQR 3.29 - 4.25) vs. 3.79 ± 0.52 (IQR 3.40 - 4.03)). We conclude that chemotherapy does not affect tumor fluorescence or identification of retained cancer cells at margins.

Abstract 4333: Association of TP53 mutation status with clinical outcomes in patients with EGFR mutated non-small cell lung cancer (NSCLC)

Introduction:

Molecular characterization of tumors is critical in the modern treatment of NSCLC. Epidermal Growth Factor Receptor (EGFR) and p53 are commonly mutated genes in NSCLC with independent prognostic implications, but the significance of the co-existence of these mutations inpatients (pts) with Stage IV NSCLC is not well established. Herein, we describe the relationship of EGFR and TP53 mutations (MT) in pts with Stage 4 or recurrent NSCLC and their correlation with pt demographics and therapeutic outcomes.

Study Design:

We conducted a retrospective analysis of Stage 4 and recurrent EGFR MT (+) NSCLC pts with TP53 MT status determined by the Gene Sequence Analysis Panel obtained at the Abramson Cancer Center between 6/1/2012 and 2/1/2014. Overall survival (OS) and progression-free survival (PFS) were estimated for the TP53 MT (+) and wild type (WT) cohorts from the date of diagnosis.

Results:

Thirty-six EGFR (+) pts were identified, of whom 26 (72%) were TP53 MT (+). Pt characteristics were similar between cohorts, except for a higher rate of bone metastasis in pts with p53 WT (p = 0.07, Table 1). Median potential follow-up for OS was 15.1 mos. 60% of patients in TP53 WT group received TKI compared to 69% in TP53 MT (+). Of the 36 pts, 9 (25%). have died. A trend towards shorter median OS was seen in pts with p53 MT. (p = 0.08). PFS did not correlate with p53 MT status (p = 0.53).

Conclusion:

Coexistence of p53 MT and EGFR MT may be associated with shorter survival. Larger sample size and longer clinical follow up will be necessary to determine if these differences are statistically significant and whether TP53 MT status is an independent prognostic factor in EGFR MT NSCLC.

Citation Format: Saman Ahmed, Charu Aggarwal, Rosemarie Mick, Joshua Bauml, Roger Cohen, Stephan Kadauke, Trisha Sterlicchi, Tracey L. Evans, John C. Kucharczuk, Charu Desphande, Jennifer J D Morrissette, Robert Daber, Corey J. Langer. Association of TP53 mutation status with clinical outcomes in patients with EGFR mutated non-small cell lung cancer (NSCLC). [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4333. doi:10.1158/1538-7445.AM2015-4333

The impact of extent and location of mediastinal lymph node involvement on survival in Stage III non-small cell lung cancer patients treated with definitive radiotherapy

PURPOSE

Several surgical series have identified subcarinal, contralateral, and multilevel nodal involvement as predictors of poor overall survival in patients with Stage III non-small-cell lung cancer (NSCLC) treated with definitive resection. This retrospective study evaluates the impact of extent and location of mediastinal lymph node (LN) involvement on survival in patients with Stage III NSCLC treated with definitive radiotherapy.

METHODS AND MATERIALS

We analyzed 106 consecutive patients with T1-4 N2-3 Stage III NSCLC treated with definitive radiotherapy at the University of Pennsylvania between January 2003 and February 2009. For this analysis, mediastinal LN stations were divided into four mutually exclusive groups: supraclavicular, ipsilateral mediastinum, contralateral mediastinum, and subcarinal. Patients' conditions were then analyzed according to the extent of involvement and location of mediastinal LN stations.

RESULTS

The majority (88%) of patients received sequential or concurrent chemotherapy. The median follow-up time for survivors was 32.6 months. By multivariable Cox modeling, chemotherapy use (hazard ratio [HR]: 0.21 [95% confidence interval (CI): 0.07-0.63]) was associated with improved overall survival. Increasing primary tumor [18F]-fluoro-2-deoxy-glucose avidity (HR: 1.11 [CI: 1.06-1.19]), and subcarinal involvement (HR: 2.29 [CI: 1.11-4.73]) were significant negative predictors of overall survival. On univariate analysis, contralateral nodal involvement (HR: 0.70 [CI: 0.33-1.47]), supraclavicular nodal involvement (HR: 0.78 [CI: 0.38-1.67]), multilevel nodal involvement (HR: 0.97 [CI: 0.58-1.61]), and tumor size (HR: 1.04 [CI: 0.94-1.14]) did not predict for overall survival. Patients with subcarinal involvement also had lower rates of 2-year nodal control (51.2% vs. 74.9%, p = 0.047) and 2-year distant control (28.4% vs. 61.2%, p = 0.043).

CONCLUSIONS

These data suggest that the factors that determine oncologic outcome in Stage III NSCLC patients treated with definitive radiotherapy are distinct from those observed in patients who undergo surgical resection. The ultimate efficacy of radiation in locally advanced NSCLC is dependent on the intrinsic biology of the tumor.

Intraluminal migration of surgical drains after transhiatal esophagogastrectomy: radiographic findings and clinical relevance

OBJECTIVE

The objectives of our study were to review our experience with a group of patients in whom contrast examinations after transhiatal esophagogastrectomy and gastric pull-through revealed intraluminal migration of a surgical drain and to describe the radiographic appearance and clinical relevance of this phenomenon.

CONCLUSION

Our findings indicate that intraluminal migration of a surgical drain after transhiatal esophagogastrectomy is an infrequent but serious phenomenon that hinders or prevents healing of an anastomotic leak. Radiologists should be aware of this phenomenon and should be able to recognize the findings of an intraluminal drain on contrast examinations. When such drains are identified, we believe that they should be promptly withdrawn or removed to facilitate healing of anastomotic leaks.

Complications of Video-Assisted Thoracoscopic Lung Biopsy in Patients with Interstitial Lung Disease

BACKGROUND

Current guidelines recommend surgical lung biopsy for diagnosis of interstitial lung diseases (ILDs) in selected patients. To shed light on the risk-benefit ratio for this recommendation, we examined the morbidity and mortality associated with video-assisted thoracoscopic surgical (VATS) lung biopsy in a group of outpatients.

METHODS

A retrospective cohort study was conducted of 68 consecutive ambulatory patients with radiographically apparent interstitial lung disease (ILD) referred for VATS biopsy during a 6-year period. Incidence of postoperative mortality, prolonged air leaks, pneumonias, and re-admissions were calculated. Risk factors for complications of surgery were examined.

RESULTS

Three deaths occurred within 60 days after biopsy for a mortality rate of 4.4% (95% confidence interval [CI], 1% to 12%), and 19.1% (95% CI, 11% to 31%) experienced one or more complications of surgery. Risk factors for morbidity included preoperative dependence on oxygen therapy and pulmonary hypertension. The three patients who died had usual interstitial pneumonia on their biopsy specimen and were reintubated postoperatively for acute lung injury. Aggregation of articles published over the past 10 years reporting on surgical lung biopsy for the diagnosis of ILD yielded a postoperative mortality rate of 2% to 4.5%.

CONCLUSIONS

VATS lung biopsy for diagnosis of ILD, even in ambulatory patients, is not an entirely benign procedure. Biopsy rarely may trigger an acute exacerbation of usual interstitial pneumonitis. The risk of postoperative complications appears to be greatest in those dependent on oxygen and those who have pulmonary hypertension. This information may be used in weighing the risk-benefit ratio of biopsy in individual patients.

Parasternal intercostal muscle remodeling in severe chronic obstructive pulmonary disease

Studies in experimental animals indicate that chronic increases in neural drive to limb muscles elicit a fast-to-slow transformation of fiber-type proportions and myofibrillar proteins. Since neural drive to the parasternal intercostal muscles (parasternals) is chronically increased in patients with severe chronic obstructive pulmonary diseases (COPDs), we carried out the present study to test the hypothesis that the parasternals of COPD patients exhibit an increase in the proportions of both slow fibers and slow myosin heavy chains (MHCs). Accordingly, we obtained full thickness parasternal muscle biopsies from the third interspace of seven COPD patients (mean +/- SE age: 59 +/- 4 yr) and seven age-matched controls (AMCs). Fiber typing was done by immunohistochemistry, and MHC proportions were determined by SDS-PAGE followed by densitometry. COPD patients exhibited higher proportions of slow fibers than AMCs (73 +/- 4 vs. 51 +/- 3%; P < 0.01). Additionally, COPD patients exhibited higher proportions of slow MHC than AMCs (56 +/- 4 vs. 46 +/- 4%, P < 0.04). We conclude that the parasternal muscles of patients with severe COPD exhibit a fast-to-slow transformation in both fiber-type and MHC proportions. Previous workers have demonstrated that remodeling of the external intercostals, another rib cage inspiratory muscle, elicited by severe COPD is characterized by a slow-to-fast transformation in both fiber types and MHC isoform proportions. The physiological significance of this difference in remodeling between these two inspiratory rib cage muscles remains to be elucidated.

Anterior surgical approaches to the thoracic outlet

OBJECTIVES

The anatomy of the thoracic outlet is complex, and the optimum surgical approach to pathologic disease at this location is controversial. Although the Dartevelle approach to the apex seems to be a safer and more direct approach, this technique has not been widely adopted in the United States. We have used this approach for pathologic disease at the thoracic outlet and modified it. Our experience is described in this article.

METHODS

A retrospective review was performed on all patients who underwent an anterior approach between December 1997 and May 2003.

RESULTS

There were 42 patients who underwent anterior approaches to pathologic disease at the level of the outlet. Diagnosis included apical non-small cell lung cancers (20 patients), osteosarcoma (2 patients), spinal cord compression (5 patients), solitary metastasis (4 patients), and benign lesions (11 patients). There were 22 female and 20 male patients with ages ranging from 26 to 82 years (mean age, 54.6 years). There were 25 complications in 14 patients and 1 in-hospital death. A transmanubrial approach was used in 14 patients, the standard Dartevelle technique was used in 8 patients, and a transclavicular approach with reapproximation of the clavicle was used in 20 patients. Reapproximation failed in 5 patients (3/3 patients who underwent fixation with mini-plates and 2/17 patients with sternal wires).

CONCLUSIONS

The anterior approach is a useful adjunct to a thoracic surgeon's armamentarium. When a transclavicular approach is optimal, division and reapproximation of the clavicle are feasible. In our experience, reapproximation with wires is superior to plates and screws.

Comparative study of subxiphoid versus video-thoracoscopic pericardial "window"

BACKGROUND

It remains undefined whether surgical subxiphoid drainage or thoracoscopic pericardial "window" is the optimal operative approach to pericardial effusion. We hypothesized that the true window into the pleural space created by the latter might improve the duration of freedom from recurrent effusion.

METHODS

We conducted a retrospective chart review of indications, preoperative and intraoperative variables, morbidity, recurrence, and survival.

RESULTS

Fifty-six patients underwent the subxiphoid procedure and 15 underwent the thoracoscopic procedure. Echocardiographic evidence of tamponade was present before 8 of 10 thoracoscopic procedures (80%) and 43 of 56 subxiphoid procedures (81%) for which descriptions of hemodynamics were available. In addition, non-pericardial procedures were performed in 10 (67%) and 18 (32%) patients, respectively (p = 0.020). Anesthesia time was longer at thoracoscopy (117.1 +/- 32.4 vs 81.1 +/- 25.5 minutes; p < 0.001). Procedural morbidity was higher after thoracoscopy (4 [27%] vs 1 [2%]; p = 0.006), but was generally minor. Hospital mortality tended to be higher after the subxiphoid procedure (7 [13%] vs 0 [0%]; p = 0.332), but none of the deaths was procedure-related. Follow-up was complete for 65 patients (92%). Recurrence occurred in 1 thoracoscopy patient (8%) and 5 subxiphoid patients (10%) (p = 1.000). Mean time to recurrence by Kaplan-Meier analysis trends were longer after thoracoscopy (36.1 vs 11.4 months; p = 0.16), and multivariate analysis identified the thoracoscopic approach as an independent predictor of freedom from recurrence (relative risk, 0.41; p = 0.014).

CONCLUSIONS

Operative time and minor procedural morbidity are higher with thoracoscopic pericardial window, but long-term control of effusion seemed to be better than after subxiphoid surgical drainage.

Radiofrequency Ablation: Emerging Therapy for the Small Pulmonary Nodule?

Traditional approaches to small pulmonary nodules have ranged from serial radiographic surveillance to transthoracic needle aspiration to surgical resection for diagnosis. Once the diagnosis of non-small-cell lung cancer is secured, lobectomy remains the gold standard treatment. Nevertheless, advances in image-guided technology and radiofrequency thermal ablation techniques have allowed for diagnostic sampling of lesions with concomitant therapeutic thermal ablation. The role these techniques will play in the treatment of patients with primary lung cancer remains undefined. This review (1) examines the basic technology of radiofrequency ablation; (2) provides an update on current clinical experience with this technique; and (3) explores the role of radiofrequency ablation in the treatment scheme of patients with non-small-cell lung cancer.

Familial massive leiomyoma with esophageal leiomyomatosis: an unusual presentation in a father and his 2 daughters

Esophageal leiomyomatosis and leiomyoma are benign neoplastic lesions composed of proliferating smooth muscle cells. Although rare, these 2 conditions may occur simultaneously in an individual patient. Symptomatic patients often require surgical management. We describe the first reported cases of family members presenting with esophageal leiomyomatosis and concomitant massive esophageal leiomyoma.

Catamenial pneumothorax: optimal hormonal and surgical management

OBJECTIVE

To provide further information addressing the etiology, optimal hormonal management and surgical management in catamenial pneumothorax (CP).

METHODS

We retrospectively analyzed records of all female patients operated on for spontaneous pneumothorax at a university hospital between January 1993 and March 2002.

RESULTS

In eight of 24 patients, pneumothoraces were timed with menses. In all, the right side was involved. Seven patients were on hormonal medications pre-operatively and six post-operatively. All six patients taking estrogen/progesterone replacement had recurrences pre-operatively and two of three had recurrences post-operatively while on these medications. No patient suffered a pneumothorax either pre- or post-operatively while taking a gonadotropin releasing hormone agonist (two and three patients, respectively). Intraoperative findings included diaphragmatic implants [5] diaphragmatic fenestrations [4], apical blebs [2] and visceral pleural implants [2]. All pathology was specifically addressed at the time of surgery. Pleural space management included mechanical pleurodesis in seven and pleurectomy with talc insufflation in 1. Follow-up ranged from 27 to 63 months with a mean of 48 months. Three patients developed post-operative recurrences. One was managed without intervention and two required additional procedures.

CONCLUSION

Catamenial pneumothorax is under appreciated, representing up to one-third of women with spontaneous pneumothorax. Hormonal agents that allow for menses are ineffective. Gonadotropin releasing hormone agonists should be considered as part of the pre-operative or post-operative management in high risk patients. Our findings suggest that an additional intervention to augment pleural symphysis at the level of the diaphragm should be performed.

Lung Cancer in Transplant Recipients

HYPOTHESIS

That aggressive surgical treatment of lung cancer (LC) is justified by stage-based outcome in immunosuppressed solid organ transplant recipients.

DESIGN

Case series.

SETTING

University hospital.

PATIENTS

Lung cancer developed in 15 patients (0.28%) among a solid organ transplant recipient population of 5400 accrued at our institution over a 25-year period.

MAIN OUTCOME MEASURES

Smoking prevalence, subtypes and stages of LC represented, operative morbidity, and survival.

RESULTS

The mean time from transplantation to the diagnosis of LC was 76 months (range, 9-192 months). Eight patients received kidneys; 3, lungs; and 4, hearts. Only 11 patients (73%) had a smoking history (mean, 66 pack-years). The following carcinomas developed in our patient population: adenocarcinoma, 6 patients; squamous cell, 5; large cell undifferentiated, 2; bronchoalveolar, 1; and small cell, 1. Eight patients (53%) presented with inoperable stage IIIB or IV disease. The remaining patients presented in stages IA (n = 2), IB (n = 1), IIB (n = 2), and IIIA (n = 2); all underwent resection. No major postoperative complications occurred. All patients with stage IIIB or greater disease with or without treatment died quickly (mean survival, 1.4 months; range, 0.33-3.0 months). All patients with stage IIB or less remain alive a mean of 37 months after resection. Patients with stage IIIA survived only a mean of 6.0 months despite resection.

CONCLUSIONS

Regarding LCs in transplant recipients compared with LCs in the nontransplant population, we find that (1) there is an increased incidence among nonsmokers; (2) death occurs rapidly in unresected patients; (3) resection carries a low morbidity rate; and (4) resection seems to offer a high chance of cure in those with cancers staged IIB or less.

Evolving options in the management of esophageal perforation

Esophageal perforation remains a devastating event that is difficult to diagnose and manage. The majority of injuries are iatrogenic and the increasing use of endoscopic procedures can be expected to lead to an even higher incidence of esophageal perforation in coming years. Accurate diagnosis and effective treatment depend on early recognition of clinical features and accurate interpretation of diagnostic imaging. Outcome is determined by the cause and location of the injury, the presence of concomitant esophageal disease, and the interval between perforation and initiation of therapy. The overall mortality associated with esophageal perforation can approach 20%, and delay in treatment of more than 24 hours after perforation can result in a doubling of mortality. Surgical primary repair, with or without reinforcement, is the most successful treatment option in the management of esophageal perforation and reduces mortality by 50% to 70% compared with other interventional therapies.

Simple technique for maximal thoracic muscle harvest

We present a modification of technique for standard muscle flap harvest, the placement of cutaneous traction sutures. This technique allows for maximal dissection of the thoracic muscles even through minimal incisions. Through improved exposure and traction, complete dissection of the muscle bed can be performed and the tissue obtained maximized. Because more muscle bulk is obtained with this technique, the need for a second muscle may be prevented.

Bronchial sleeve resection for posttransplant stricture

Nonanastomotic bronchial stenosis is a rare complication of lung transplantation. We report a case of a bilateral lung transplant recipient who experienced recalcitrant stenosis of the bronchus intermedius. All attempts at conservative management failed, and the stricture was successfully treated by a parenchymal-sparing segmental sleeve resection. Although rare, this is an important technique in the management of this difficult problem.

Weerda diverticuloscope: novel use to remove embedded esophageal foreign bodies

Embedded sharp foreign bodies of the cervical esophagus represent a clinical challenge. Initial attempts at removal are usually undertaken by nonsurgical endoscopists who are often successful with blunt objects. Unsuccessful attempts with sharp objects, however, can result in distal migration, mucosal damage, and frank perforation. Thoracic surgeons are often called on for cervical esophagotomy after endoscopic attempts have failed. This report describes the novel use of a Weerda diverticuloscope for removal of a dental appliance with metallic hooks embedded in the cervical esophagus.