Associations of tissue tumor mutational burden and mutational status with clinical outcomes in KEYNOTE-042: pembrolizumab versus chemotherapy for advanced PD-L1-positive NSCLC.

BACKGROUND: We evaluated whether tissue tumor mutational burden (tTMB) and STK11, KEAP1, and KRAS mutations have clinical utility as biomarkers for pembrolizumab monotherapy versus platinum-based chemotherapy in patients with programmed death ligand 1 (PD-L1)-positive (tumor proportion score ≥1%) advanced/metastatic non-small-cell lung cancer (NSCLC) without EGFR/ALK alterations in the phase III KEYNOTE-042 trial. PATIENTS AND METHODS: This retrospective exploratory analysis assessed prevalence of tTMB and STK11, KEAP1, and KRAS mutations determined by whole-exome sequencing of tumor tissue and matched normal DNA and their associations with outcomes in KEYNOTE-042. Clinical utility of tTMB was assessed using a prespecified cut point of 175 mutations/exome. RESULTS: Of 793 patients, 345 (43.5%) had tTMB ≥175 mutations/exome and 448 (56.5%) had tTMB <175 mutations/exome. No association was observed between PD-L1 expression and tTMB. Continuous tTMB score was associated with improved overall survival (OS) and progression-free survival among patients receiving pembrolizumab (Wald test, one-sided P < 0.001) but not those receiving chemotherapy (Wald test, two-sided P > 0.05). tTMB ≥175 mutations/exome was associated with improved outcomes for pembrolizumab versus chemotherapy, whereas tTMB <175 mutations/exome was not {OS: hazard ratio, 0.62 [95% confidence interval (CI) 0.48-0.80] and 1.09 (95% CI 0.88-1.36); progression-free survival: 0.75 (0.59-0.95) and 1.27 (1.04-1.55), respectively}. Improved OS [hazard ratio (95% CI)] for pembrolizumab versus chemotherapy was observed regardless of STK11 [STK11 mutant (n = 33): 0.37 (0.16-0.86), STK11 wild-type (n = 396): 0.83 (0.65-1.05)]; KEAP1 [KEAP1 mutant (n = 64): 0.75 (0.42-1.35), KEAP1 wild-type (n = 365): 0.78 (0.61-0.99)], or KRAS [KRAS mutant (n = 69): 0.42 (0.22-0.81); KRAS wild-type (n = 232): 0.86 (0.63-1.18)] mutation status. CONCLUSION: tTMB with a cut point of ≥175 mutations/exome is a potential predictive biomarker for pembrolizumab monotherapy for advanced/metastatic PD-L1 tumor proportion score ≥1% NSCLC. Pembrolizumab is a standard first-line treatment in this setting regardless of STK11, KEAP1, or KRAS mutation status.

Characterization of the PilN, PilO and PilP type IVa pilus subcomplex.

Type IVa pili are bacterial nanomachines required for colonization of surfaces, but little is known about the organization of proteins in this system. The Pseudomonas aeruginosa pilMNOPQ operon encodes five key members of the transenvelope complex facilitating pilus function. While PilQ forms the outer membrane secretin pore, the functions of the inner membrane-associated proteins PilM/N/O/P are less well defined. Structural characterization of a stable C-terminal fragment of PilP (PilP(Δ71)) by NMR revealed a modified ß-sandwich fold, similar to that of Neisseria meningitidis PilP, although complementation experiments showed that the two proteins are not interchangeable likely due to divergent surface properties. PilP is an inner membrane putative lipoprotein, but mutagenesis of the putative lipobox had no effect on the localization and function of PilP. A larger fragment, PilP(Δ18-6His), co-purified with a PilN(Δ44)/PilO(Δ51) heterodimer as a stable complex that eluted from a size exclusion chromatography column as a single peak with a molecular weight equivalent to two heterotrimers with 1:1:1 stoichiometry. Although PilO forms both homodimers and PilN-PilO heterodimers, PilP(Δ18-6His) did not interact stably with PilO(Δ51) alone. Together these data demonstrate that PilN/PilO/PilP interact directly to form a stable heterotrimeric complex, explaining the dispensability of PilP's lipid anchor for localization and function.

Ki67 expression in the primary tumor predicts for clinical benefit and time to progression on first-line endocrine therapy in estrogen receptor-positive metastatic breast cancer.

We examined whether baseline Ki67 expression in estrogen receptor-positive (ER+) primary breast cancer correlates with clinical benefit and time to progression on first-line endocrine therapy and survival in metastatic disease. Ki67 values and outcome information were retrieved from a prospectively maintained clinical database and validated against the medical records; 241 patients with metastatic breast cancer were included--who had ER+ primary cancer with known Ki67 expression level--and received first-line endocrine therapy for metastatic disease. Patients were assigned to low (<10 %), intermediate (10-25 %), or high (>25 %) Ki67 expression groups. Kaplan-Meier survival curves were plotted and multivariate analysis was performed to assess association between clinical and immunohistochemical variables and outcome. The clinical benefit rates were 81, 65, and 55 % in the low (n = 32), intermediate (n = 103), and high (n = 106) Ki67 expression groups (P = 0.001). The median times to progression on first-line endocrine therapy were 20.3 (95 % CI, 17.5-38.5), 10.8 (95 % CI, 8.9-18.8), and 8 (95 % CI, 6.1-11.1) months, respectively (P = 0.0002). The median survival times after diagnosis of metastatic disease were also longer for the low/intermediate compared to the high Ki67 group, 52 versus 30 months (P < 0.0001). In multivariate analysis, high Ki67 expression in the primary tumor remained an independent adverse prognostic factor in metastatic disease (P = 0.001). Low Ki67 expression in the primary tumor is associated with higher clinical benefit and longer time to progression on first-line endocrine therapy and longer survival after metastatic recurrence.

Short communication: characterization of early postpartum estrous behavior and ovulation in lactating dairy cows using radiotelemetry.

The objective of this study was to describe early postpartum estrous behavior and ovulation in lactating dairy cows using radiotelemetry. Cows (n=50) were continuously monitored for behavioral estrus with a radiotelemetric system, HeatWatch II (CowChips LLC, Manalapan, NJ), from d 14 to approximately d 49 postpartum. Blood collection for analysis of progesterone and ovarian ultrasonography were performed once weekly starting on d 14. First ovulation was associated with behavioral estrus in 5 cows and occurred at 28.2±10.8 d (mean±SD; range 17 to 40 d). The average duration of estrus was 6.0±4.9 h (range 3 to 12.2 h), and the mean number of standing events was 18.4±8.9 (range 4 to 26). Based on progesterone concentrations of ≥1 ng/mL, estimated first postpartum ovulation occurred at 25.1±10.4 d (range 10 to 49 d) for 38 animals without evidence of behavioral estrus. The interval to estimated first ovulation without behavioral estrus was not different from the interval to first ovulation associated with behavioral estrus. Level of milk production and body condition score loss did not affect the interval to estimated first ovulation without estrus or first ovulation associated with estrus. Six animals did not show evidence of ovulation based on progesterone concentration, whereas 1 cow showed evidence of estrous behavior on the day before removal from the study. The majority of first postpartum ovulations (38/43; 88.4%) were not associated with behavioral estrus.

Randomized trial of polychromatic blue-enriched light for circadian phase shifting, melatonin suppression, and alerting responses.

Wavelength comparisons have indicated that circadian phase-shifting and enhancement of subjective and EEG-correlates of alertness have a higher sensitivity to short wavelength visible light. The aim of the current study was to test whether polychromatic light enriched in the blue portion of the spectrum (17,000 K) has increased efficacy for melatonin suppression, circadian phase-shifting, and alertness as compared to an equal photon density exposure to a standard white polychromatic light (4000 K). Twenty healthy participants were studied in a time-free environment for 7 days. The protocol included two baseline days followed by a 26-h constant routine (CR1) to assess initial circadian phase. Following CR1, participants were exposed to a full-field fluorescent light (1 × 1014 photons/cm2/s, 4000 K or 17,000 K, n = 10/condition) for 6.5 h during the biological night. Following an 8 h recovery sleep, a second 30-h CR was performed. Melatonin suppression was assessed from the difference during the light exposure and the corresponding clock time 24 h earlier during CR1. Phase-shifts were calculated from the clock time difference in dim light melatonin onset time (DLMO) between CR1 and CR2. Blue-enriched light caused significantly greater suppression of melatonin than standard light ((mean ±â€¯SD) 70.9 ±â€¯19.6% and 42.8 ±â€¯29.1%, respectively, p < 0.05). There was no significant difference in the magnitude of phase delay shifts. Blue-enriched light significantly improved subjective alertness (p < 0.05) but no differences were found for objective alertness. These data contribute to the optimization of the short wavelength-enriched spectra and intensities needed for circadian, neuroendocrine and neurobehavioral regulation.

The Crystal Backlighter Imager: A spherically bent crystal imager for radiography on the National Ignition Facility.

The Crystal Backlighter Imager (CBI) is a quasi-monochromatic, near-normal incidence, spherically bent crystal imager developed for the National Ignition Facility (NIF), which will allow inertial confinement fusion capsule implosions to be radiographed close to stagnation. This is not possible using the standard pinhole-based area-backlighter configuration, as the self-emission from the capsule hotspot overwhelms the backlighter signal in the final stages of the implosion. The CBI mitigates the broadband self-emission from the capsule hot spot by using the extremely narrow bandwidth inherent to near-normal-incidence Bragg diffraction. Implementing a backlighter system based on near-normal reflection in the NIF chamber presents unique challenges, requiring the CBI to adopt novel engineering and operational strategies. The CBI currently operates with an 11.6 keV backlighter, making it the highest energy radiography diagnostic based on spherically bent crystals to date. For a given velocity, Doppler shift is proportional to the emitted photon energy. At 11.6 keV, the ablation velocity of the backlighter plasma results in a Doppler shift that is significant compared to the bandwidth of the instrument and the width of the atomic line, requiring that the shift be measured to high accuracy and the optics aligned accordingly to compensate. Experiments will be presented that used the CBI itself to measure the backlighter Doppler shift to an accuracy of better than 1 eV. These experiments also measured the spatial resolution of CBI radiographs at 7.0 µm, close to theoretical predictions. Finally, results will be presented from an experiment in which the CBI radiographed a capsule implosion driven by a 1 MJ NIF laser pulse, demonstrating a significant (>100) improvement in the backlighter to self-emission ratio compared to the pinhole-based area-backlighter configuration.

Collagen IV levels are elevated in the serum of patients with primary breast cancer compared to healthy volunteers.

Collagen IV is a major component of the vascular basement membrane and may be a marker of angiogenesis. Serum levels of this protein are elevated in some human cancers. Our objectives were to compare collagen IV levels in the serum of breast cancer patients and healthy women and to examine changes during preoperative chemotherapy. Sera from 51 patients with stage II-III breast cancer and 55 healthy controls were analysed. Collagen IV level was measured by a commercially available sandwich enzyme link immunoassay. Baseline serum levels were compared between cancer patients and healthy women and paired pre- and post-chemotherapy measurements were also performed in 39 patients who received preoperative chemotherapy and were correlated with response to therapy. The median serum collagen IV concentration was significantly higher in cancer patients (166 microg l(-1)) than in healthy women (115 microg l(-1)), P<0.001. Chemotherapy induced a significant further increase in serum collagen IV (167 microg l(-1) prechemo vs 206 microg l(-1) postchemo, P=0.001). There were no correlations between baseline collagen IV levels and response to therapy, age, clinical stage or HER2 status. In conclusion, patients with breast cancer have elevated levels of collagen IV compared to healthy women and collagen IV levels increase further during chemotherapy.

On the system stability and calibration of the image plate/scanner system for plasma diagnosis at the National Ignition Facility.

At the National Ignition Facility (NIF), storage phosphor image plates (IP) are used extensively for recording x-rays, charged particles, and neutrons. For x-ray imaging and spectroscopy, absolute and relative calibrations are important for extracting plasma information from the diagnostics. We use Fuji MS, SR, and TR image plates that have been cut to fit custom diagnostic envelopes. The image plates are scanned on a General Electric FLA 7000 IP flying spot scanner. Calibrations for sensitivity, spatial scale, and temperature dependent fade are applied. During a set of recent calibrations, we noticed large shifts in the absolute calibration of the image plate system. The possible source of these shifts is discussed. We discuss scanner stability and a method for calibration. We discuss the fade and temperature effects of the image plates and how this correction is applied within the NIF environment. We also compare our NIF GE FLA 7000 IP scanner with a new General Electric Amersham Typhoon IP scanner.

Duvelisib treatment is associated with altered expression of apoptotic regulators that helps in sensitization of chronic lymphocytic leukemia cells to venetoclax (ABT-199).

Duvelisib, an oral dual inhibitor of PI3K-δ and PI3K-γ, is in phase III trials for the treatment of chronic lymphocytic leukemia (CLL) and indolent non-Hodgkin's lymphoma. In CLL, duvelisib monotherapy is associated with high iwCLL (International Workshop on Chronic Lymphocytic Leukemia) and nodal response rates, but complete remissions are rare. To characterize the molecular effect of duvelisib, we obtained samples from CLL patients on the duvelisib phase I trial. Gene expression studies (RNAseq, Nanostring, Affymetrix array and real-time RT-PCR) demonstrated increased expression of BCL2 along with several BH3-only pro-apoptotic genes. In concert with induction of transcript levels, reverse phase protein arrays and immunoblots confirmed increase at the protein level. The BCL2 inhibitor venetoclax induced greater apoptosis in ex vivo-cultured CLL cells obtained from patients on duvelisib compared with pre-treatment CLL cells from the same patients. In vitro combination of duvelisib and venetoclax resulted in enhanced apoptosis even in CLL cells cultured under conditions that simulate the tumor microenvironment. These data provide a mechanistic rationale for testing the combination of duvelisib and venetoclax in the clinic. Such combination regimen (NCT02640833) is being evaluated for patients with B-cell malignancies including CLL.

A single tube RT-PCR assay for the detection of mosquito-borne flaviviruses.

Mosquito-borne flaviviruses include several important agents of human disease and have provided striking examples of emerging infections. In this study we present the design and validation of a single tube RT-PCR assay using a pair of consensus primers for the detection of mosquito-borne flaviviruses. Sequencing of the amplicons permits the species identification. The assay was validated using RNA from the yellow fever virus vaccine strain and from representative strains of dengue viruses 1, 2, 3 and 4, West Nile virus, Kunjin virus (a clade of West Nile virus), and St. Louis encephalitis virus.

A single-gene biomarker identifies breast cancers associated with immature cell type and short duration of prior breastfeeding.

The pathogenesis of breast cancers that do not express estrogen receptors or Her-2/neu receptors (ER-/HER2- phenotype) is incompletely understood. We had observed markedly elevated gene expression of gamma-aminobutyric acid type A (GABA(A)) receptor subunit pi (GABApi, GABRP) in some breast cancers with ER-/HER2- phenotype. In this study, transcriptional profiles (TxPs) were obtained from 82 primary invasive breast cancers by oligonucleotide microarrays. Real-time reverse transcription-polymerase chain reaction (RT-PCR) was used to measure GABApi gene expression in a separate cohort of 121 invasive breast cancers. GABApi gene expression values from TxP and RT-PCR were standardized and compared with clinicopathologic characteristics in the 203 patients. GABApi gene expression was increased in 16% of breast cancers (13/82 TxP, 20/ 121 RT-PCR), particularly in breast cancers with ER-/HER2- phenotype (60%), and breast cancers with basal-like genomic profile (60%). The profile of genes coexpressed with GABApi in these tumors was consistent with an immature cell type. In multivariate linear regression analysis, the level of GABApi gene expression was associated with ER-/HER2- phenotype (P < 0.0001), younger age at diagnosis (P = 0.0003), and shorter lifetime duration of breastfeeding (< or = 6 months) in all women (P = 0.017) and specifically in parous women (P = 0.013). GABApi gene expression was also associated with combinations of high grade with ER-/HER2- phenotype (P = 0.002), and with Hispanic ethnicity (P = 0.036). GABApi gene expression is increased in breast cancers of immature (undifferentiated) cell type and is significantly associated with shorter lifetime history of breastfeeding and with high-grade breast cancer in Hispanic women.

Gene expression profiles predict complete pathologic response to neoadjuvant paclitaxel and fluorouracil, doxorubicin, and cyclophosphamide chemotherapy in breast cancer.

PURPOSE: The goal of this study was to examine the feasibility of developing a multigene predictor of pathologic complete response (pCR) to sequential weekly paclitaxel and fluorouracil + doxorubicin + cyclophosphamide (T/FAC) neoadjuvant chemotherapy regimen for breast cancer. PATIENTS AND METHODS: All patients underwent one-time pretreatment fine-needle aspiration to obtain RNA from the cancer for transcriptional profiling using cDNA arrays containing 30721 human sequence clones. Analysis was performed after profiling, and 42 patients' clinical results were available, 24 of which were used for predictive marker discovery; 18 patients' results were used as an independent validation set. RESULTS: Thirty-one percent of patients had pCR (six discovery and seven validation), defined as disappearance of all invasive cancer in the breast after completion of chemotherapy. We could identify no single marker that was sufficiently associated with pCR to be used as an individual predictor. A multigene model with 74 markers (P

Reconciling quantitative ultrasound of the calcaneus with X-ray-based measurements of the central skeleton.

Osteoporosis is frequently undiagnosed before fracture because of the lack of availability of instruments to quantitate bone mass. To evaluate the utility of quantitative ultrasound (QUS) of the calcaneus to diagnose osteoporosis, we determined bone mineral density (BMD) of the posterior-arterior spine, total hip, and femoral neck by dual-energy X-ray absorptiometry (DXA) and QUS in 312 women aged 50 years and older. A risk factor assessment (simple calculated osteoporosis risk estimation [SCORE]) also was quantitated in all women. Ninety-four of the 312 women were diagnosed as osteoporotic based on T scores < or = -2.5 at the spine, total hip, and/or femoral neck. The sensitivity of the individual central sites for the diagnosis of osteoporosis was 49% at the spine (46 of 94 women), 32% at the total hip (30 of 94 women), and 81% at the femoral neck (76 of 94 women). At a QUS T score < or = -1, the peripheral technique had a sensitivity of 62% and a specificity of 72%. Combining a QUS T score of < or = -1 followed by a risk factor assessment of women with a QUS T score > or = -0.99 using a cut point of 11 increased sensitivity to 81% (comparable with femoral neck DXA) but decreased specificity to 58%. If peripheral QUS measurements and risk factor assessment are the only tools employed before initiation of therapy, the benefits of increased ease of diagnosis will need to be balanced against potentially unnecessary treatment in some normal patients and lack of treatment in some osteoporotic patients.

Axonal degeneration is an early pathological feature in autoimmune-mediated demyelination in mice.

Multiple sclerosis (MS) is an inflammatory disorder of the central nervous system (CNS), characterised by focal destruction of myelin. Although it is evident that the immune system contributes to tissue destruction in MS, it is still unclear as to whether this immune response is a cause or a consequence of the disease process. In addition, there is debate over the contribution of axonal damage to clinical progression. We have described a murine model of relapsing-remitting MS (RR-MS), the most common form of the disease, following immunisation with the myelin component, myelin oligodendrocyte glycoprotein (MOG). We showed that a single injection of a MOG peptide (MOG(35-55)) in NOD/Lt mice induces a paralytic relapsing disease with extensive plaque-like demyelination. This model also mimics many of the immunological features associated with RR-MS. To investigate the relationship between clinical episodes, inflammation, and demyelination/remyelination, we analysed lesions during each attack and remission over the course of the disease, using histological, immunocytochemical, and electron microscopy (EM) techniques. We show that morphological features of lesions in our model resemble those observed in MS. Indeed, severe inflammation and demyelination coincide with the peak of clinical episodes while remissions are characterised by quiescent plaques. Furthermore, axonal damage is evident from the earliest stage of the disease and increases in severity with subsequent relapses. These data establish that in the model of MS-like disease, the peak of clinical episodes coincides with severe inflammation and demyelination and that axonal pathology correlates with clinical progression.

Peripheral nerve binding patterns of anti-sulphatide antibodies in HIV-infected individuals.

HIV-positive plasma samples from patients with and without neuropathy and with high titre anti-GalS antibodies showed strong binding to the myelin membrane of both fixed and unfixed human sciatic nerve specimens. This staining pattern was also seen with a plasma sample from a patient with IgM paraproteinaemic inflammatory demyelinating neuropathy with anti-GalS IgM antibody. Teased nerve fibres incubated with these anti-GalS antibodies from both HIV and non-HIV plasma samples showed immunofluorescence at the paranodal regions and Schmidt-Lanterman incisures. These data support a potential role for these antibodies in the aetiology of HIV-associated immune mediated neuropathies.

High titre anti-sulphatide antibodies in HIV-infected individuals.

Plasma samples from 35 individuals with human immunodeficiency virus (HIV) infection but without peripheral neuropathy were screened by enzyme linked immunosorbent assay (ELISA) for IgM and IgG antibodies against sulphatide (GalS). Five of these were shown to contain raised anti-GalS IgM antibody titres, while six had raised IgG titres. All plasma samples screened were compared to an internal neurological disease control which contained raised anti-GalS IgM antibody titres. Anti-GalS IgM antibody titres in the HIV cohort ranged between 200 and 2000 arbitrary units/litre (AU/l), whereas, IgG titres were between 200 and 10,000 AU/l. Two of four plasma samples from HIV-infected individuals with neuropathy (HIV+PN) also showed IgM reactivity with GalS; one also binding to the gangliosides GM1, GD1a, GD1b and GT1b. The other two samples showed IgG reactivity against GalS. These data indicate that antibodies against GalS occur more frequently in HIV infection than in HIV-seronegative individuals with and without neurological disease and may participate in the pathogenesis of neuropathies associated with HIV infection.

Comprehensive detection and identification of human coronaviruses, including the SARS-associated coronavirus, with a single RT-PCR assay.

The SARS-associated human coronavirus (SARS-HCoV) is a newly described, emerging virus conclusively established as the etiologic agent of the severe acute respiratory syndrome (SARS). This study presents a single-tube RT-PCR assay that can detect with high analytical sensitivity the SARS-HCoV, as well as several other coronaviruses including other known human respiratory coronaviruses (HCoV-OC43 and HCoV-229E). Species identification is provided by sequencing the amplicon, although a rapid screening test by restriction enzyme analysis has proved to be very useful for the analysis of samples obtained during the SARS outbreak in Toronto, Canada.

Mechanism of ethanol-induced aggregation in whole blood.

Effects of ethanol on blood clotting and platelet aggregation have been reported in many models, but its in vitro actions in whole blood, impedance aggregometry have not been reported. We investigated the effect of ethanol in vitro in whole blood and platelet rich plasma of humans and rats, as measured by impedance aggregometry. Ethanol (34 to 170 mM) induced concentration-dependent aggregation in whole blood but not platelet rich plasma. In further studies in rats, aggregation was inhibited by pretreatment of whole blood with the prostacyclin analog iloprost or the enzyme apyrase, which degrades ADP to AMP. Levels of ethanol which produced aggregation in whole blood were also associated with concentration-dependent hemolysis. Based on the requirement for whole blood for ethanol-induced aggregation, the inhibitory effect of apyrase and our observation of hemolysis, and previous studies which have demonstrated the potential contribution of ADP from lysed red blood cells to platelet aggregation, we conclude that ethanol-induced aggregation in whole blood is mediated by erythrocyte lysis and the ADP released from these cells.

A double-'blind' placebo-controlled study of nitazoxanide in the treatment of cryptosporidial diarrhoea in AIDS patients in Mexico.

Sixty-six patients with human immunodeficiency virus infection and diarrhoea caused by Cryptosporidium parvum were enrolled in a double-'blind' placebo-controlled study to evaluate the safety and efficacy of nitazoxanide in the treatment of cryptosporidiosis related to the acquired immune deficiency syndrome. Patients were randomly assigned to one of 3 treatment groups and received either 500 mg twice daily of nitazoxanide, 1000 mg twice daily of nitazoxanide, or placebo orally for 14 d; the patients on nitazoxanide then crossed over to placebo while the placebo patients crossed over to nitazoxanide therapy at either the high or low dose depending on their randomization. Three post-treatment faecal examinations were conducted on days 15, 22 and 29 following initiation of treatment: patients were considered 'cured' if none revealed any C. parvum oocysts. Both doses of nitazoxanide produced parasitological cure rates superior to the placebo responses (12/19 [63%, P = 0.016] for patients receiving 1 g/d and 10/15 [67%, P = 0.013] for those receiving 2 g/d). Parasitological cure was correlated with the complete resolution of the diarrhoeal syndrome in 19 of the 22 treated patients who were considered parasitologically cured (86%). Both doses of nitazoxanide were well tolerated by the patients.

Rigid bronchoscopy in the twenty-first century.

Rigid bronchoscopy, a procedure more than 100 years old, now has been performed in three centuries. The "open tube" bronchoscope provides safe access to the lower airways and has proved to be compatible with newer, more sophisticated therapies as they have been introduced into the practice of bronchology. The twenty-first century surely will provide the bronchoscopist with exciting new diagnostic and therapeutic tools for the management of lung diseases, and it is likely that the rigid bronchoscope will continue to play an important role in delivering these tools to the airways. Pulmonologists need to appreciate the use of this classic instrument and prevent rigid bronchoscopy from becoming a forgotten art.