Wedge Resection Versus Segmentectomy for Older Patients With Stage IA Non-Small-Cell Lung Cancer

INTRODUCTION

Anatomic lung resection remains the standard of care for early-stage non-small-cell lung cancer (NSCLC), but wedge resection may offer similar survival in older adult patients. The objective of this study was to evaluate the survival of patients aged 80 y and older undergoing wedge resection versus segmentectomy for stage IA NSCLC using a large clinical registry.

METHODS

Patients aged 80 y and older in the National Cancer Database who underwent wedge resection or segmentectomy for cT1a-b N0 M0 NSCLC between 2004 and 2018 were identified for an analysis. Survival was assessed using multivariable Cox proportional hazards analysis, propensity-score matching, and inverse probability weighting. A subgroup analysis of patients who underwent lymph node evaluation with their wedge resection or segmentectomy was also performed.

RESULTS

Of the 2690 patients identified, 2272 (84%) underwent wedge resection and 418 (16%) underwent segmentectomy. Wedge resection was associated with worse 5-year overall survival relative to segmentectomy in multivariable-adjusted (adjusted Hazard Ratio: 1.26, [1.06-1.51], P = 0.01) and propensity score-matched analysis (49% [95% confidence interval {CI}: 42%-55%] versus 59% [95% CI: 52%-65%], P = 0.02). Among a subgroup of 1221 wedge resection and 347 segmentectomy patients who also received intraoperative lymph node evaluation, however, there were no significant differences in 5-year survival in multivariable-adjusted (adjusted Hazard Ratio: 1.12, [0.90-1.39], P = 0.31) or propensity score-matched analysis (55% [95% CI: 48%-62%] versus 61% [95% CI: 54%-68%], P = 0.10).

CONCLUSIONS

In this national analysis, there were no significant differences in survival between older adult patients with stage IA NSCLC who underwent wedge resection versus segmentectomy when a lymph node evaluation was performed.

Genomic description of human clinical Aspergillus fumigatus isolates, California, 2020

Aspergillus fumigatus, an environmental mold, causes life-threatening infections. Studies on the phylogenetic structure of human clinical A. fumigatus isolates are limited. Here, we performed whole genome sequencing of 24 A. fumigatus isolates collected from 18 patients in U.S. healthcare facilities in California. Single-nucleotide polymorphism (SNP) differences between patient isolates ranged from 187 to 70 829 SNPs. For five patients with multiple isolates, we calculated the within-host diversities. Three patients had a within-host diversity that ranged from 4 to 10 SNPs and two patients ranged from 2 to 16 977 SNPs. Findings revealed highly diverse A. fumigatus strains among patients and two patterns of diversity for isolates that come from the same patient, low and extremely high diversity.

The Risk of Postoperative Complications After Major Elective Surgery in Active or Resolved COVID-19 in the United States

OBJECTIVE

To assess the association between the timing of surgery relative to the development of Covid-19 and the risks of postoperative complications.

SUMMARY BACKGROUND DATA

It is unknown whether patients who recovered from Covid-19 and then underwent a major elective operation have an increased risk of developing postoperative complications.

METHODS

The risk of postoperative complications for patients with Covid-19 undergoing 18 major types of elective operations in the Covid-19 Research Database was evaluated using multivariable logistic regression. Patients were grouped by time of surgery relative to SARS-CoV-2 infection; that is, surgery performed: (1) before January 1, 2020 ("pre-Covid-19"), (2) 0 to 4 weeks after SARS-CoV-2 infection ("peri-Covid-19"), (3) 4 to 8 weeks after infection ("early post-Covid-19"), and (4) ≥8 weeks after infection ("late post-Covid-19").

RESULTS

Of the 5479 patients who met study criteria, patients with peri-Covid-19 had an elevated risk of developing postoperative pneumonia [adjusted odds ratio (aOR), 6.46; 95% confidence interval (CI): 4.06-10.27], respiratory failure (aOR, 3.36; 95% CI: 2.22-5.10), pulmonary embolism (aOR, 2.73; 95% CI: 1.35-5.53), and sepsis (aOR, 3.67; 95% CI: 2.18-6.16) when compared to pre-Covid-19 patients. Early post-Covid-19 patients had an increased risk of developing postoperative pneumonia when compared to pre-Covid-19 patients (aOR, 2.44; 95% CI: 1.20-4.96). Late post-Covid-19 patients did not have an increased risk of postoperative complications when compared to pre-Covid-19 patients.

CONCLUSIONS

Major, elective surgery 0 to 4 weeks after SARS-CoV-2 infection is associated with an increased risk of postoperative complications. Surgery performed 4 to 8 weeks after SARS-CoV-2 infection is still associated with an increased risk of postoperative pneumonia, whereas surgery 8 weeks after Covid-19 diagnosis is not associated with increased complications.

A National Analysis of Minimally Invasive Vs Open Segmentectomy for Stage IA Non-Small-Cell Lung Cancer

The objective of this study was to compare long-term outcomes of open vs minimally invasive (MIS) segmentectomy for early stage non-small-cell lung cancer (NSCLC), which has not been previouslyevaluated using national studies. Outcomes of open vs MIS segmentectomy for clinical T1, N0, M0 NSCLC in the National Cancer Data Base (2010-2015) were evaluated using propensity score matching. Of the 39,351 patients who underwent surgery for stage IA NSCLC from 2010 to 2015, 770 underwent segmentectomy by thoracotomy and 1056 by MIS approach (876 thoracoscopic [VATS], 180 robotic). The MIS to open conversion rate was 6.7% (n = 71). After propensity score matching, all baseline characteristics were well-balanced between the open (n = 683) and MIS (n = 683) groups. When compared to the open group, the MIS group had shorter median length of stay (4 vs 5 days, P< 0.001) and lower 30-day mortality (0.6% vs 1.9%, P = 0.037). There were no significant differences between MIS and open groups with regard to 30-day readmission (5.0% vs 3.7%, P = 0.43), or upstaging from cN0 to pN1/N2/N3 (3.1% vs 3.6%, P = 0.89). The MIS approach was associated with similar long-term overall survival as the open approach (5-year survival: 62.3% vs 63.5%, P = 0.89; multivariable-adjusted hazard ratio: 0.99, 95% Confidence Intervial (CI): 0.82-1.21, P = 0.96). In this national analysis of open vs MIS segmentectomy for clinical stage IA NSCLC, MIS was associated with shorter length of stay and lower perioperative mortality, and similar nodal upstaging and 5-year survival when compared to segmentectomy via thoracotomy. MIS segmentectomy does not appear to compromise oncologic outcomes for clinical stage IA NSCLC.

Sublobar resection is associated with decreased survival for patients with early stage large-cell neuroendocrine carcinoma of the lung

OBJECTIVES

Sublobar resection (SLR) for early non-small-cell lung carcinoma (NSCLC) has been shown to have a survival rate similar to that of lobectomy. Large-cell neuroendocrine carcinoma (LCNEC) of the lung, although treated like an NSCLC, has a poor prognosis compared to NSCLC. We sought to determine if outcomes are poor in patients with early stage LCNEC treated with SLR versus lobectomy.

METHODS

We searched for patients with pathological stage I LCNEC ≤3 cm within the National Cancer Database between 2004 and 2014. Propensity score matching was used to compare the 5-year overall survival rate of patients having SLR (wedge or segmentectomy) to that of patients having a lobectomy. Patients were matched for age, node sampling, comorbidity score, tumour size, insurance status and other factors. Patients who received neoadjuvant therapy were excluded. Kaplan-Meier methods were used for analysis.

RESULTS

A total of 1011 patients met the inclusion criteria: 263 were treated with SLR (223 wedges and 40 segmentectomies) and 748 patients, with lobectomy. Patients who received SLR were older, had more comorbidities and smaller tumours. On unadjusted Kaplan-Meier analysis, patients who had SLR had decreased 5-year overall survival compared to those who had a lobectomy (37.9% vs 56.6%, P < 0.001). Propensity score matching (1:1) across 12 demographic and tumour variables yielded 185 patients per group with 34 segmentectomies and 151 wedge resections in the SLR cohort. On Kaplan-Meier analysis of the matched cohort, patients who had SLR had a worse 5-year overall survival rate compared to those who had a lobectomy (41.5% vs 60.3%; P = 0.001).

CONCLUSIONS

SLR for early stage LCNEC is associated with a lower 5-year overall survival rate compared to lobectomy on unadjusted and propensity matched analyses.

The Oldest Old: A National Analysis of Outcomes for Patients 90 Years or Older With Lung Cancer

BACKGROUND

Most clinicians will encounter patients 90 years or older with non-small cell lung cancer (NSCLC), but evidence that informs treatment decisions for this extremely elderly population is lacking. This study evaluated outcomes associated with treatment strategies for this nonagenarian population.

METHODS

Treatment and overall survival for patients 90 years and older with NSCLC in the National Cancer Data Base (2004-2014) were evaluated using logistic regression, the Kaplan-Meier method, and multivariable Cox proportional hazard models.

RESULTS

The majority (n = 4152, 57.6%) of the 7205 patients 90 years or older with stage I-IV NSCLC did not receive any therapy. For the entire cohort, receiving treatment was associated with significantly better survival when compared with no therapy (5-year survival, 9.3% [95% confidence interval [CI], 8.0%-10.7%] vs 1.7% [95% CI, 1.2%-2.2%]; multivariable adjusted hazard ratio, 0.53; P < .001). Stage I patients had the most pronounced survival benefit with treatment (median survival, 27.4 months vs 10.0 months with no treatment; P < .001). Among this subset of patients with stage I disease (n = 1430), only 12.7% (n = 182) had surgery and 33% (n = 471) had no therapy. In these stage I patients surgery was associated with significantly better 5-year survival (33.7% [95% CI, 25.4%-42.1%]) than nonoperative therapy (17.1% [95% CI, 13.7%-20.8%]) and no therapy (6.2% [95% CI, 3.8%-9.4%]).

CONCLUSIONS

Therapy for nonagenarians with NSCLC is associated with a significant survival benefit but is not used in most patients. Treatment should not be withheld for these "oldest old" patients based on their age alone but should be considered based on stage and patient preferences in a multidisciplinary setting.

Mechanochromic Stretchable Electronics

Soft and stretchable electronics are promising for a variety of applications such as wearable electronics, human-machine interfaces, and soft robotics. These devices, which are often encased in elastomeric materials, maintain or adjust their functionality during deformation, but can fail catastrophically if extended too far. Here, we report new functional composites in which stretchable electronic properties are coupled to molecular mechanochromic function, enabling at-a-glance visual cues that inform user control. These properties are realized by covalently incorporating a spiropyran mechanophore within poly(dimethylsiloxane) to indicate with a visible color change that a strain threshold has been reached. The resulting colorimetric elastomers can be molded and patterned so that, for example, the word "STOP" appears when a critical strain is reached, indicating to the user that further strain risks device failure. We also show that the strain at color onset can be controlled by layering silicones with different moduli into a composite. As a demonstration, we show how color onset can be tailored to indicate a when a specified frequency of a stretchable liquid metal antenna has been reached. The multiscale combination of mechanochromism and soft electronics offers a new avenue to empower user control of strain-dependent properties for future stretchable devices.

Surgical treatment for early stage non-small cell lung cancer

Surgery is the standard of care for early stage non-small cell lung cancer. There is significant debate about the type of operation most effective for lung cancer. Minimally invasive techniques like video-assisted (VATS) and robot-assisted thoracoscopic surgery (RATS) have been shown to reduce postoperative complications and shorten hospitalization. However, there remains skepticism about their oncologic effectiveness when compared to an open approach, though recent literature suggests no differences in upstaging or survival between VATS and thoracotomy. The extent of resection for early lung cancer also remains a matter of debate. Lobectomy remains the preferred operation and is associated with better survival and lower locoregional recurrence, but there is increased interest in the role of sublobar resections. Sublobar resections have similar mortality to lobar resections in small ground glass-predominant tumors. We examine the literature surrounding these controversies in this review.

Design of interventional studies in thoracic surgery

Interventional studies differ from observational studies in that one or more specific interventions are evaluated. Randomized controlled trials remain the gold standard for interventional studies and can take different forms. In surgical studies, the three types of randomized controlled trials most commonly encountered are: (I) trials that compare two different medical treatments for patients undergoing surgery; (II) trials that evaluate two different surgical techniques and (III) studies that compare surgery vs. non-operative management. When an intervention is to be evaluated but a randomized controlled trial is not feasible, alternative interventional study designs may be considered.

Anatomic thoracoscopic segmentectomy for early-stage lung cancer

Over the past 20 years, there have been significant advancements in thoracoscopic surgical techniques as well as in lung cancer screening protocols, which have identified greater numbers of smaller lung tumors (<2 cm) that are more frequently operable and curable. These advancements have led to new interest in the thoracoscopic (VATS) approach to segmentectomy. This article will discuss the outcomes and technical considerations associated with VATS segmentectomy.

A new 7,8-euphadien-type triterpenoid from Brackenridgea nitida and Bleasdalea bleasdalei that inhibits DNA polymerase beta

Bioassay-guided fractionation of extracts prepared from Brackenridgea nitida and Bleasdalea bleasdalei, using an assay to detect DNA polymerase beta inhibition, resulted in the isolation of the inhibitory principle, (24E)-3beta-hydroxy-7,24-euphadien-26-oic acid (1), a new euphane triterpenoid. The structure of 1 was established on the basis of HRMS and 1D and 2D NMR spectroscopic methods and was confirmed further by X-ray crystallographic analysis. Compound 1 inhibited rat DNA polymerase beta with an IC(50) value of 23 microM in the presence of bovine serum albumin (BSA) and 9.7 microM in the absence of BSA, consistent with the possibility that 1 may be of utility in vivo. This possibility was further supported by the finding that 1 potentiated the inhibitory action of the anticancer drug bleomycin in cultured P-388D(1) cells, reducing the number of viable cells by 48% when employed at a concentration of 25 microM in the presence of an otherwise nontoxic (75 nM) concentration of bleomycin. Compound 1 is the first euphane-type triterpenoid found to inhibit DNA polymerase beta.

Use of COMPARE analysis to discover functional analogues of bleomycin

Bleomycin was used as the reference compound in a COMPARE analysis to identify extracts in the National Cancer Institute's Natural Products Repository exhibiting cytotoxicity profiles similar to this antitumor agent. One of the extracts so identified was a CH(2)Cl(2)-methanol extract prepared from Gymnosporia trigyna, which effected relaxation of supercoiled pSP64 DNA in the presence of Cu(2+). Bioassay-guided fractionation using DNA strand-scission activity as an end point resulted in the isolation of four active principles. These were identified as syringaldehyde (1), (-)-syringaresinol (2), (+)-catechin (3), and (+)-epicatechin (4). Compounds 1 and 2 represent a new type of DNA strand-scission agent.

Naturally occurring alkylresorcinols that mediate DNA damage and inhibit its repair

A study of di- and trihydroxyalkylbenzenes and bis(dihydroxyalkylbenzenes) revealed that several compounds were capable of both mediating Cu(2+)-dependent DNA cleavage and strongly inhibiting DNA polymerase beta. The most potent DNA polymerase beta inhibitors were bis(dihydroxyalkylbenzenes) 5 and 6; compounds 3 and 4 were also reasonably potent. The length of the alkyl substituent was found to be a critical element for DNA polymerase beta inhibition, since compounds 1 and 2 had shorter substituents than 3 and were completely inactive. Lineweaver-Burk plots revealed that 3, 4, and 6 exhibited mixed inhibition of DNA polymerase beta with respect to both activated DNA and dTTP. Unsaturated bis(dihydroxyalkylbenzene) 5 was a pure noncompetitive inhibitor with respect to both substrates and associated avidly with the enzyme whether or not it was in complex with its substrate(s). Copper(II)-mediated DNA cleavage was the most pronounced for the trihydroxyalkylbenzene 3, consistent with an earlier report [Singh, U. S., Scannell, R. T., An, H., Carter, B. J., and Hecht, S. M. (1995) J. Am. Chem. Soc. 117, 12691-12699]. Unsaturated bis(dihydroxyalkylbenzene) 5 was the next most active DNA cleaving agent, followed by the dihydroxyalkylbenzene 4. The saturated bis(dihydroxyalkylbenzene) (6) did not cleave DNA well in a cell-free system under the conditions studied but nonetheless potentiated the effects of bleomycin to the greatest extent in cell culture studies. Interestingly, compound 5 produced a reduction in the numbers of viable cells when incubated in the presence of bleomycin and a further reduction in the numbers of viable cells in the presence of both bleomycin and Cu(2+). The same effect was noted to a lesser extent for compound 3 but not for 4 or 6.

[Flavonoids and anthraquinone from Dioscorea bulbifera L]

OBJECTIVE

To study the chemical constituents of Dioscorea bulbifera.

METHOD

Column chromatography with silica gel was employed for the isolation and purification of constituents. The structures were elucidated by UV, IR, MS, 1H NMR and 13C NMR analyses.

RESULT

Three compounds were obtained and elucidated as 3,7-dimethoxy-5,4'-dihydroxyflavone; 3,7-dimethoxy-5,3',4'-trihydroxyflavone and emodin.

CONCLUSION

These compounds were separated from D. bulbifera for the first time.

Pentacyclic triterpenoids from Freziera sp. that inhibit DNA polymerase beta

In a survey of crude plant extracts for DNA polymerase 1 inhibitors, a methyl ethyl ketone extract prepared from Freziera sp. exhibited potent inhibition of DNA polymerase beta. Bioassay-guided fractionation of the extract, guided by an assay to detect DNA polymerase beta inhibition, resulted in the isolation of six active pentacyclic triterpenoids (1-6). These triterpenoids had IC50 values ranging from 7.5 to 16 microM in the presence of bovine serum albumin (BSA) and 2.6-5.8 microM in the absence of BSA, consistent with the possibility that these inhibitors may be of use in vivo.

DNA polymerase beta inhibitors from Baeckea gunniana

Crude plant extracts were surveyed for their ability to inhibit DNA polymerase beta. A methyl ethyl ketone extract prepared from Baeckea gunniana was identified as a potent inhibitor of the enzyme. Bioassay-guided fractionation of the extract, using an assay to monitor the inhibitory potential of individual fractions toward DNA polymerase beta, led to the isolation of four active ursane and oleanane triterpenoids (1-4). Inhibitory principle 1 is a new natural product, and 2 is a novel compound. Their structures were established as 3 beta-hydroxyrus-12,19(29)-dien-28-oic acid (1) and 3 beta-hydroxyrus-18,20(30)-dien-28-oic acid (2) by spectroscopic analysis and by comparison with the data for the structurally related compound ursolic acid (4). Also isolated as a DNA polymerase beta inhibitor was oleanolic acid (3). Compounds 1-4 had IC50 values of 5.3-8.5 microM as inhibitors of polymerase beta in the presence of bovine serum albumin (BSA) and 2.5-4.8 microM in the absence of BSA.

Harbinatic acid, a novel and potent DNA polymerase beta inhibitor from Hardwickia binata

Bioassay-guided fractionation of an active methyl ethyl ketone extract of Hardwickia binata, using an assay sensitive to DNA polymerase beta inhibition, resulted in the isolation of a potent inhibitor. This proved to be a novel diterpenoid, which has been named harbinatic acid (1). The structure of 1 was established as 3alpha-O-trans-p-coumaroyl-7-labden-15-oic acid from spectroscopic analysis and by comparison with the published data for a structurally related compound. Compound 1 strongly inhibited calf thymus DNA polymerase beta, with an IC(50) value of 2.9 microM.

bis-5-Alkylresorcinols from Panopsis rubescens that inhibit DNA polymerase beta

Bioassay-guided fractionation of Panopsis rubescens, using an assay to detect DNA polymerase beta inhibition, led to the isolation of two new bis-5-alkylresorcinols (1 and 2), in addition to one known bis-5-alkylresorcinol (3). The structures of 1-3 were established as 1,3-dihydroxy-5-[14'-(3' ',5' '-dihydroxyphenyl)-cis-4'-tetradecenyl]benzene (1), 1, 3-dihydroxy-5-[14'-(3' ',5' '-dihydroxyphenyl)-cis-7'-tetradecenyl]benzene (2), and 1, 3-dihydroxy-5-[14'-(3' ',5' '-dihydroxyphenyl)tetradecenyl]benzene (3), respectively, by spectroscopic and chemical analyses. Compounds 1-3 exhibited potent inhibition of calf thymus DNA polymerase beta, with IC50 values of 7.5, 6.5, and 5.8 microM, respectively.