Impacts of Positive Margins and Surgical Extent on Outcomes After Early-Stage Lung Cancer Resection.

BACKGROUND: Sublobar resection of early-stage non-small cell lung cancer (NSCLC) is increasingly considered appropriate but may compromise margins compared with lobectomy. This study evaluated resection extent, margin status, and survival in patients with clinical stage I NSCLC. METHODS: Patients with clinical T1-2 N0 M0 NSCLC in the National Cancer Database (2006-2020) who were treated with primary surgery were compared stratified by margin status. The potential benefit of radiation was explored in subgroup analysis of patients who underwent sublobar resection with positive margins. RESULTS: Positive margins occurred in 5089 (2.8%) of 181,824 patients and were more common in sublobar resections compared with lobectomy (4.3% vs 2.4%; P < .001). Sublobar resection had the strongest association with positive margins in multivariable analysis (odds ratio, 2.06; 95% CI, 1.91-2.23; P < .001). Patients with positive margins were more likely to undergo both adjuvant chemotherapy (16% vs 13%; P < .001) and radiation (17% vs 1%; P < .001) but had worse survival in univariate analysis (44.0% 5-year overall survival vs 69.2%; P < .001) and multivariable Cox analysis (hazard ratio, 1.71; 95% CI, 1.63-1.78; P < .001) in the entire cohort, as well as in a univariate subset analysis of lobectomy (46.9% vs 70.4%; P < .001) and sublobar resection (37.5% vs 64.1%; P < .001). Postoperative radiation for patients who underwent sublobar resection with positive margins did not improve 5-year overall survival (36.3% for irradiated patients vs 38.3% for nonirradiated patients; P = .57), and patients who underwent sublobar resection with positive margins who were treated with radiation had survival inferior to that of patients who underwent lobectomy with negative margins. CONCLUSIONS: Positive margins occur more frequently after sublobar resection of clinical stage I NSCLC compared with lobectomy. Patients with positive margins have worse survival than patients who undergo complete resection and are not rescued by postoperative radiation.

Barriers to Completing Low Dose Computed Tomography Scan for Lung Cancer Screening.

INTRODUCTION: Annual low-dose computed tomography (LDCT) screening has been shown to reduce lung cancer mortality in high-risk individuals by detecting the disease at an earlier stage. This study aims to assess the barriers to completing LDCT in a cohort of patients who were determined eligible for lung cancer screening (LCS). METHODS: We performed a single institution, mixed methods, cross-sectional study of patients who had a LDCT ordered from July to December 2022. We then completed phone surveys with patients who did not complete LDCT to assess knowledge, attitude, and perceptions toward LCS. RESULTS: We identified 380 patients who met inclusion criteria, including 331 (87%) who completed LDCT and 49 (13%) who did not. Patients who completed a LDCT and those who did not were similar regarding age, sex, race, primary language, household income, body mass index, median pack years, and quit time. Positive predictors of LDCT completion were: meeting USPSTF guidelines (97.9% vs 81.6%), being married (58.3% vs 44.9%), former versus current smokers (55% vs 41.7%), personal history of emphysema (60.4% vs 42.9%), and family history of lung cancer (13.9% vs 4.1%) (all P < .05). Of the patients who participated in the phone survey, only 7% of respondents thought they were high risk for developing lung cancer despite attending a shared decision-making visit and only 10% wanted to re-schedule their LDCT. CONCLUSION: There exist barriers to completing LDCT even after patients are identified as eligible and complete a shared decision-making visit secondary to knowledge barriers, misperceptions, and patient disinterest.

Randomized controlled trials in lung cancer surgery: How are we doing?

Objective: Randomized control trials are considered the highest level of evidence, yet the scalability and practicality of implementing randomized control trials in the thoracic surgical oncology space are not well described. The aim of this study is to understand what types of randomized control trials have been conducted in thoracic surgical oncology and ascertain their success rate in completing them as originally planned. Methods: The ClinicalTrials.gov database was queried in April 2023 to identify registered randomized control trials performed in patients with lung cancer who underwent surgery (by any technique) as part of their treatment. Results: There were 68 eligible randomized control trials; 33 (48.5%) were intended to examine different perioperative patient management strategies (eg, analgesia, ventilation, drainage) or to examine different intraoperative technical aspects (eg, stapling, number of ports, port placement, ligation). The number of randomized control trials was relatively stable over time until a large increase in randomized control trials starting in 2016. Forty-four of the randomized control trials (64.7%) were open-label studies, 43 (63.2%) were conducted in a single facility, 66 (97.1%) had 2 arms, and the mean number of patients enrolled per randomized control trial was 236 (SD, 187). Of 21 completed randomized control trials (31%), the average time to complete accrual was 1605 days (4.4 years) and average time to complete primary/secondary outcomes and adverse events collection was 2125 days (5.82 years). Conclusions: Given the immense investment of resources that randomized control trials require, these findings suggest the need to scrutinize future randomized control trial proposals to assess the likelihood of successful completion. Future study is needed to understand the various contributing factors to randomized control trial success or failure.

What Is an Adequate Margin During Sublobar Resection of ≤3 cm N0 Subsolid Lung Adenocarcinomas?

BACKGROUND: Sublobar resection offers noninferior survival vs lobectomy for ≤2 cm non-small cell lung cancer and is commonly used for subsolid tumors. Although data exist for solid tumors, the minimum adequate margin of resection for subsolid adenocarcinomas remains unclear. METHODS: This was a retrospective review of 1101 adenocarcinoma resections at our institution from 2006 to 2022. Inclusion criteria were tumors ≤3 cm with ≥10% radiographic ground glass, excised by sublobar resection. Exclusions were positive nodes or positive or unreported margin. The primary outcome was the rate of local recurrence (LR) at multiple thresholds of margin distance. The relationship between margin distance and solid component size was also explored. RESULTS: Inclusion criteria were met by 194 patients. Median (interquartile range) tumor diameter and margin distance were 12 mm (9-17 mm) and 10 mm (5-17 mm), respectively. Median follow-up was 42.5 months. There was a progressive increase in LR with diminishing margin (0.1-cm decrements) from 1.5 cm to 0.5 cm. The difference in the rate of LR between "over" (n = 143) and "under" (n = 51) was most significant at 0.5 cm (8 of 51 [15.7%] vs 6 of 143 [4.2%]; P = .01) but did not reach α adjusted for multiple comparisons. On Cox regression for LR-free survival, margin ≤0.5 cm (P = .19) and solid component percentage (P = .14) trended to significance. Combining these using a ratio of margin distance-to-solid component size, a ratio of ≤1 showed a significantly higher rate of LR (7 [14.3%] vs 2 [2.0%], P = .009). Treatment of LRs provided at least intermediate-term survival in 87% of recurrences (median postrecurrence follow-up was 44 months). CONCLUSIONS: During sublobar resection of subsolid lung adenocarcinomas, a margin distance-to-solid component size ratio of >1.0 appears to be a more reliable factor than margin distance alone to minimize local recurrence. Local recurrence, however, may not impact survival in patients with subsolid adenocarcinomas if timely treatment is administered.

The Impact of Immunotherapy Use in Stage IIIA (T1-2N2) NSCLC: A Nationwide Analysis.

Introduction: Multiple clinical trials have revealed the benefit of immunotherapy (IO) for NSCLC, including unresectable stage III disease. Our aim was to investigate the impact of IO use on treatment and outcomes of potentially resectable stage IIIA NSCLC in a broader nationwide patient cohort. Methods: We queried the National Cancer Database (2004-2019) for patients with stage IIIA (T1-2N2) NSCLC. Treatment and survival were evaluated with descriptive statistics, logistic regression, Kaplan-Meier analysis, and Cox proportional hazards modeling. Results: Overall, 5.5% (3777 of 68,335) of patients received IO. IO use was uncommon until 2017, but by 2019, it was given to 40.1% (1544 of 2308) of stage IIIA patients. The increased use of IO after 2017 was associated with increased definitive chemoradiation treatment (54.2% [6800 of 12,535] from years 2017 to 2019 versus 46.9% [26,251 of 55,914] from 2004 to 2016, p < 0.001) and less use of surgery (18.1% [2266 of 12,535] from years 2017 to 2019 versus 22.0% [12,300 of 55,914] from 2004 to 2016, p < 0.001). IO treatment was associated with significantly better 5-year survival in the entire cohort (36.9% versus 23.4%, p < 0.001) and the subsets of patients treated with chemoradiation (37.2% versus 22.7%, p < 0.001) and surgery (48.6% versus 44.3%, p < 0.001). Pneumonectomy use decreased with increased IO treatment (5.1% of surgical patients [116 of 2266] from years 2017 to 2019 versus 9.2% [1127 of 12,300] from 2004 to 2016, p < 0.001). Conclusions: Increased use of IO was associated with a change in treatment patterns and improved survival for patients with stage IIIA(N2) NSCLC.

Lepidic-Type Lung Adenocarcinomas: Is It Safe to Observe for Growth Before Treating?

BACKGROUND: Lepidic-type adenocarcinomas (LPAs) can be multifocal, and treatment is often deferred until growth is observed. This study investigated the potential downside of that strategy by evaluating the relationship of nodal involvement with tumor size and survival. METHODS: The impact of tumor size on lymph node involvement and survival was evaluated for National Cancer Database patients who underwent surgery without induction therapy as primary treatment for cT1-3 N0 M0 histologically confirmed LPA from 2006 to 2019 by using logistic regression, Kaplan-Meier, and Cox analyses. RESULTS: Positive nodes occurred in 442 of 8286 patients (5.3%). The incidence of having positive nodes approximately doubled with each 1-cm increment increase in size. Patients with positive nodes were more likely to have larger tumors (27 mm vs 20 mm, P < .001) and clinical ≥T2 disease (40.7% vs 26.8%, P < .001) compared with node-negative patients. However, tumor size was the only significant independent predictor of having positive nodal disease in logistic regression analysis, and this association grew stronger with each incremental centimeter increase in size. Patients with positive nodes were more likely to undergo adjuvant radiotherapy (23.5% vs 1.1%, P < .001) and chemotherapy (72.9% vs 7.9%, P < .001), and expectedly, had worse survival compared with the node-negative group in univariate (5-year overall survival, 50.9% vs 81.1%, P < .001) and multivariable (hazard ratio, 2.56; 95% CI, 2.14-3.05; P < .001) analyses. CONCLUSIONS: Nodal involvement is relatively uncommon in early-stage LPAs but steadily increases with tumor size and is associated with dramatically worse survival. These data can be used to inform treatment decisions when evaluating LPA patients.

Impact of hyperthermic intrathoracic chemotherapy (HITHOC) during resection of pleural mesothelioma on patient survival.

Background: Pleural mesothelioma (PM) is rare but portends a poor prognosis. Multimodal treatment, including aggressive surgical resection, may offer the best chance of treatment response and improved survival. Single-center studies suggest that hyperthermic intrathoracic chemotherapy (HITHOC) during surgical resection improves outcomes, but the impact of HITHOC on postoperative morbidity and survival has not been examined on a larger scale. Methods: The National Cancer Database was queried for patients undergoing resection for PM from 2006-2017. Patients were excluded if staging or survival data was incomplete. After propensity-score matching, patients who underwent HITHOC were compared to patients who did not (case-control study). Perioperative outcomes and survival were analyzed. Results: The final cohort consisted of 3,232 patients; of these, 365 patients underwent HITHOC. After propensity-score matching, receipt of HITHOC was associated with increased length of stay (12 vs. 7 days, P<0.001) and increased 30-day readmissions (9.9% vs. 4.9%, P=0.007), but decreased 30-day mortality (3.2% vs. 6.0%, P=0.017) and 90-day mortality (7.5% vs. 10.9%). Kaplan-Meier modeling demonstrated that HITHOC was associated with improved survival in the overall cohort (median 20.5 vs. 16.8 months, P=0.001). In multivariable analysis, HITHOC remained associated with improved overall survival [hazard ratio (HR) =0.80; 95% confidence interval (CI): 0.69-0.92; P=0.002], and this persisted in the propensity-matched analysis (HR =0.73; 95% CI: 0.61-0.88; P=0.001). Conclusions: Using a large national database, we describe the impact of HITHOC on survival in patients with PM. Despite observed increased short-term morbidity, in multivariable analysis HITHOC was associated with an overall survival advantage for patients undergoing surgical resection of PM.

Half of Anastomotic Leaks After Esophagectomy Are Undetected on Initial Postoperative Esophagram.

BACKGROUND: The sensitivity of fluoroscopic esophagography with oral administration of contrast material to exclude anastomotic leak after esophagectomy is not well documented, and the consequences of missing a leak in this setting have not been previously described. METHODS: We performed a retrospective cohort study of a prospectively maintained institutional database of patients undergoing esophagectomy with esophagogastric anastomosis from 2008 to 2020. Relevant details of leaks, management, and outcomes were obtained from the database and formal chart review. Statistical analysis was performed to compare patients with and without leaks and those with false-negative vs positive esophagrams. RESULTS: There were 384 patients who underwent esophagectomy with gastric reconstruction; the majority were Ivor-Lewis (82%), and 51% were wholly or partially minimally invasive. By use of a broad definition of leak, 55 patients (16.7%) developed an anastomotic leak. Of the 55 patients, 27 (49%) who ultimately were found to have a leak initially had a normal esophagram result (performed on average on postoperative day 6). Those with a normal initial esophagram result were more likely to have an uncontained leak (81% vs 29%; P < .01), to require unplanned readmission (70% vs 39%; P = .02), and to undergo reoperation (44% vs 11%; P < .01). CONCLUSIONS: Early postoperative esophagrams intended to evaluate anastomotic integrity have a low sensitivity of 51%, and leaks missed on the initial esophagram have greater clinical consequences than those identified on the initial esophagram. These findings suggest that a high index of suspicion must be maintained even after a normal esophagram result and call into question the common practice of using this test to triage patients for diet advancement.

The impact of refusing esophagectomy for treatment of locally advanced esophageal adenocarcinoma.

Objective: Patients with esophageal cancer may be reluctant to proceed with surgery due to high complication rates. This study aims to compare outcomes between eligible surgical candidates who proceeded with surgery versus those who refused surgery. Methods: Characteristics and survival of patients with locally advanced (cT3N0M0, cT1-3N+M0) mid-/distal esophageal adenocarcinoma in the National Cancer Database (2006-2019) who either proceeded with or refused surgery after chemoradiotherapy were evaluated with logistic regression, Kaplan-Meier curves, and Cox proportional hazards methods. Results: Of the 13,594 patients included in the analysis, 595 (4.4%) patients refused esophagectomy. Patients who refused surgery were older, had less distance to travel to their treatment facility, were more likely to have cN0 disease, and were more likely to be treated at a community rather than academic or integrated network program, but did not have significantly different comorbid disease distributions. On multivariable analysis, refusing surgery was independently associated with older age, uninsured, lower income, less distance to a hospital, and treatment in a community program versus an academic/research or integrated network program. Esophagectomy was associated with better survival (5-year survival 40.1% [39.2-41] vs 23.6% [19.9-27.9], P < .001) and was also independently associated with better survival in the Cox model (hazard rate, 0.78 [95% confidence interval, 0.7-0.87], P < .001). Conclusions: The results of this study can inform selected patients with resectable esophageal adenocarcinoma that their survival will be significantly diminished if surgery is not pursued. Many factors associated with refusing surgery are non-clinical and suggest that access to or support for care could influence patient decisions.

Risk of developing subsequent primary lung cancer after receiving radiation for breast cancer.

Background: Radiotherapy (RT) is integral to breast cancer treatment, especially in the current era that emphasizes breast conservation. The aim of our study was to determine the incidence of subsequent primary lung cancer after RT exposure for breast cancer over a time span of 3 decades to quantify this risk over time as modern oncologic treatment continues to evolve. Methods: The SEER (Surveillance, Epidemiology, and End Results) database was queried from 1988 to 2014 for patients diagnosed with nonmetastatic breast cancer. Patients who subsequently developed primary lung cancer were identified. Multivariable regression modeling was performed to identify independent factors associated with the development of lung cancer stratified by follow up intervals of 5 to 9 years, 10 to 15 years, and >15 years after breast cancer diagnosis. Results: Of the 612,746 patients who met our inclusion criteria, 319,014 (52%) were irradiated. primary lung cancer developed in 5556 patients (1.74%) in the RT group versus 4935 patients (1.68%) in the non-RT group. In a multivariable model stratified by follow-up duration, the overall HR of developing subsequent ipsilateral lung cancer in the RT group was 1.14 (P = .036) after 5 to 9 years of follow-up, 1.28 (P = .002) after 10 to 15 years of follow-up, and 1.30 (P = .014) after >15 years of follow-up. The HR of contralateral lung cancer was not increased at any time interval. Conclusions: The increased risk of developing a primary lung cancer secondary to RT exposure for breast cancer is much lower than previously published. Modern RT techniques may have contributed to the improved risk profile, and this updated study is important for counseling and surveillance of breast cancer patients.

Comparison of failure to rescue in younger versus elderly patients following lung cancer resection.

Objective: Failure to rescue (FTR), defined as in-hospital death following a major complication, has been increasingly studied in patients who undergo cardiothoracic surgery. This study tested the hypothesis that elderly patients undergoing lung cancer resection have greater rates of FTR compared with younger patients. Methods: Patients who underwent surgery for primary lung cancer between 2011 and 2020 and had at least 1 major postoperative complication were identified using the National Surgical Quality Improvement Program database. Patients who died following complications (FTR) were compared with those who survived in an elderly (80+ years) and younger (<80 years) cohort. Results: Of the 2823 study patients, the younger cohort comprised 2497 patients (FTR: n = 139 [5.6%]), whereas the elderly cohort comprised 326 patients (FTR: n = 39 [12.0%]). Pneumonia was the most common complication in younger (877/2497, 35.1%) and elderly patients (118/326, 36.2%) but was not associated with FTR on adjusted analysis. Increasing age was associated with FTR (adjusted odds ratio [AOR], 1.55 per decade, P < .001), whereas unplanned reoperation was associated with reduced risk (AOR, 0.55, P = .01). Within the elderly cohort, surgery conducted by a thoracic surgeon was associated with lower FTR risk (AOR, 0.29, P = .028). Conclusions: FTR following lung cancer resection was more frequent with increasing age. Pneumonia was the most common complication but not a predictor of FTR. Unplanned reoperation was associated with reduced FTR, as was treatment by a thoracic surgeon for elderly patients. Surgical therapy for complications after lung cancer resection and elderly patients managed by a thoracic specialist may mitigate the risk of death following an adverse postoperative event.

Resection of a Giant Epithelioid Hemangioendothelioma Arising from the Superior Vena Cava.

Epithelioid hemangioendothelioma is a rare malignant vascular sarcoma. Here we present a patient with a very large tumor arising from the superior vena cava, in whom a resection with negative margins was accomplished using venovenous bypass and bovine pericardial patch reconstruction of the superior vena cava.

Minimally Invasive Bilateral Stellate Ganglionectomy for Refractory Ventricular Tachycardia.

Cardiac sympathetic denervation (CSD) for refractory ventricular tachycardia (VT) has been shown to decrease VT recurrence and defibrillator shocks in patients with ischemic and nonischemic cardiomyopathy. Here and in the accompanying Video, we demonstrate the technique for minimally invasive CSD, highlight important technical points, and report surgical outcomes. CSD is accomplished through bilateral resection of the inferior one-third to one-half of the stellate ganglion en bloc with T2-T4 sympathectomy. Despite the high potential for perioperative risk, most patients do not have serious complications. We find that surgical CSD can be performed safely in an attempt to liberate patients from refractory VT.

Histone deacetylase inhibition is synthetically lethal with arginine deprivation in pancreatic cancers with low argininosuccinate synthetase 1 expression.

Arginine (Arg) deprivation is a promising therapeutic approach for tumors with low argininosuccinate synthetase 1 (ASS1) expression. However, its efficacy as a single agent therapy needs to be improved as resistance is frequently observed. Methods: A tissue microarray was performed to assess ASS1 expression in surgical specimens of pancreatic ductal adenocarcinoma (PDAC) and its correlation with disease prognosis. An RNA-Seq analysis examined the role of ASS1 in regulating the global gene transcriptome. A high throughput screen of FDA-approved oncology drugs identified synthetic lethality between histone deacetylase (HDAC) inhibitors and Arg deprivation in PDAC cells with low ASS1 expression. We examined HDAC inhibitor panobinostat (PAN) and Arg deprivation in a panel of human PDAC cell lines, in ASS1-high and -knockdown/knockout isogenic models, in both anchorage-dependent and -independent cultures, and in multicellular complex cultures that model the PDAC tumor microenvironment. We examined the effects of combined Arg deprivation and PAN on DNA damage and the protein levels of key DNA repair enzymes. We also evaluated the efficacy of PAN and ADI-PEG20 (an Arg-degrading agent currently in Phase 2 clinical trials) in xenograft models with ASS1-low and -high PDAC tumors. Results: Low ASS1 protein level is a negative prognostic indicator in PDAC. Arg deprivation in ASS1-deficient PDAC cells upregulated asparagine synthetase (ASNS) which redirected aspartate (Asp) from being used for de novo nucleotide biosynthesis, thus causing nucleotide insufficiency and impairing cell cycle S-phase progression. Comprehensively validated, HDAC inhibitors and Arg deprivation showed synthetic lethality in ASS1-low PDAC cells. Mechanistically, combined Arg deprivation and HDAC inhibition triggered degradation of a key DNA repair enzyme C-terminal-binding protein interacting protein (CtIP), resulting in DNA damage and apoptosis. In addition, S-phase-retained ASS1-low PDAC cells (due to Arg deprivation) were also sensitized to DNA damage, thus yielding effective cell death. Compared to single agents, the combination of PAN and ADI-PEG20 showed better efficacy in suppressing ASS1-low PDAC tumor growth in mouse xenograft models. Conclusion: The combination of PAN and ADI-PEG20 is a rational translational therapeutic strategy for treating ASS1-low PDAC tumors through synergistic induction of DNA damage.

Epidural Analgesia Improves Postoperative Pain Control but Impedes Early Discharge in Patients Undergoing Pancreatic Surgery.

OBJECTIVES: The aim of this study was to evaluate the impact of epidural analgesia (EA) on postoperative length of stay (LOS), expeditious discharge, and pain relief after pancreaticoduodenectomy (PD) and distal pancreatectomy (DP). METHODS: Retrospective reviews of 2014-2015 American College of Surgeons National Surgical Quality Improvement Program databases and our institutional pancreatic surgery database were conducted. RESULTS: On univariate analysis, EA was associated with statistically significant longer lengths of stay for both PD and DP. On comparative analysis at mode LOS, discharged before versus after 7 days for PD and 6 days for DP, EA was a significant predictor for the longer groups for both procedures on multivariable analysis (PD, odds ratio of 1.465, P < 0.001; DP, odds ratio of 1.471, P = 0.004). On review of our institution's pancreatic surgery database, patient-reported pain scores were significantly lower in the EA groups than intravenous narcotics groups on the day of surgery only for both PD and DP. CONCLUSIONS: Epidural analgesia was associated with longer LOS with a most pronounced effect on early discharge after surgery for patients undergoing open PD and DP. It only resulted in superior pain control on the day of surgery.

Lysosome inhibition sensitizes pancreatic cancer to replication stress by aspartate depletion.

Functional lysosomes mediate autophagy and macropinocytosis for nutrient acquisition. Pancreatic ductal adenocarcinoma (PDAC) tumors exhibit high basal lysosomal activity, and inhibition of lysosome function suppresses PDAC cell proliferation and tumor growth. However, the codependencies induced by lysosomal inhibition in PDAC have not been systematically explored. We performed a comprehensive pharmacological inhibition screen of the protein kinome and found that replication stress response (RSR) inhibitors were synthetically lethal with chloroquine (CQ) in PDAC cells. CQ treatment reduced de novo nucleotide biosynthesis and induced replication stress. We found that CQ treatment caused mitochondrial dysfunction and depletion of aspartate, an essential precursor for de novo nucleotide synthesis, as an underlying mechanism. Supplementation with aspartate partially rescued the phenotypes induced by CQ. The synergy of CQ and the RSR inhibitor VE-822 was comprehensively validated in both 2D and 3D cultures of PDAC cell lines, a heterotypic spheroid culture with cancer-associated fibroblasts, and in vivo xenograft and syngeneic PDAC mouse models. These results indicate a codependency on functional lysosomes and RSR in PDAC and support the translational potential of the combination of CQ and RSR inhibitors.

Pathologic Response to Neoadjuvant Therapy is Associated With Improved Long-term Survival in High-risk Primary Localized Malignant Peripheral Nerve Sheath Tumors.

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs) comprise a rare, aggressive subtype of soft tissue sarcoma. While surgery is the mainstay of therapy for this disease, the role of neoadjuvant therapy remains undefined. METHODS: This study reviewed patients 16 years of age and older who underwent surgical treatment for MPNST between 1974 and 2012 at the authors' institution. Univariate and multivariate analyses were performed of clinicopathologic and treatment variables predictive of disease-specific survival (DSS) and disease-free survival. RESULTS: Eighty-eight patients with primary localized MPNST underwent surgical treatment between 1974 and 2012 at our institution. Of these, 38 (43%) underwent neoadjuvant chemotherapy and had tissue available for analysis. Neoadjuvant radiation was given to 25 patients (68%). The median follow-up time for survivors was 12.5 years (range, 4 to 27 y). Nine patients (23%) had underlying MPNST. With a cutoff of ≥90% pathologic necrosis and/or fibrosis defining response, we identified 14 responders (36%). On univariate analysis, patient age, tumor size, and pathologic response were significantly associated with DSS (P=0.015, 0.011, and 0.030, respectively). CONCLUSIONS: Although the impact of neoadjuvant chemotherapy on the outcome of primary localized MPNST patients continues to be debated, this study shows that a pathologic response to therapy is associated with a significant improvement in DSS. The challenge moving forward is to determine upfront which patients will be "responders" to standard systemic therapy and which patients should be considered for newer investigational agents as part of a clinical trial.

Temozolomide regresses a doxorubicin-resistant undifferentiated spindle-cell sarcoma patient-derived orthotopic xenograft (PDOX): precision-oncology nude-mouse model matching the patient with effective therapy.

Undifferentiated spindle-cell sarcoma (USCS) is a recalcitrant cancer, resistant to conventional chemotherapy. A patient with high-grade USCS from a striated muscle was implanted orthotopically in the right biceps femoris muscle of mice to establish a patient-derived orthotopic xenograft (PDOX) model. The PDOX models were randomized into the following groups when tumor volume reached 100 mm3 : G1, control without treatment; G2, doxorubicin (DOX) (3 mg/kg, intraperitoneal [i.p.] injection, weekly, for 2 weeks); G3, temozolomide (TEM) (25 mg/kg, p.o., daily, for 14 days). Tumor size and body weight were measured with calipers and a digital balance twice a week. TEM significantly inhibited tumor volume growth compared to the untreated control and the DOX-treated group on day 14 after treatment initiation: control (G1): 343 ± 78 mm3 ; DOX (G2): 308 ± 31 mm3 , P = 0.272; TEM (G3): 85 ± 21 mm3 , P < 0.0001. TEM significantly regressed the tumor volume compared to day 0 (P = 0.019). There were no animal deaths in any group. The body weight of treated mice was not significantly different in any group. Tumors treated with DOX were comprised of spindle-shaped viable cells without apparent necrosis or inflammatory changes. In contrast, tumors treated with TEM showed extensive tumor necrosis. The present study demonstrates the potential power of matching the patient with an effective drug and saving the patient needless toxicity from ineffective drugs.