Development and validation of a novel nomogram for predicting good neoangiogenesis after encephaloduroarteriosynangiosis in patients with moyamoya disease and type 2 diabetes mellitus: a case-control study.

OBJECTIVE: Diabetes is often linked to poorer outcomes in patients with moyamoya disease (MMD). However, experience has shown that certain individuals with diabetes have favorable outcomes after encephaloduroarteriosynangiosis (EDAS). The authors aimed to develop a nomogram to predict good neoangiogenesis in patients with MMD and type 2 diabetes mellitus (T2DM) to aid neurosurgeons in the identification of suitable candidates for EDAS. METHODS: Adults with MMD and T2DM who underwent EDAS between June 2004 and December 2018 were included in the analysis. In total, 126 patients (213 hemispheres) with MMD and T2DM from the Fifth Medical Centre of the Chinese PLA General Hospital were included and randomly divided into training (152 hemispheres) and internal validation (61 hemispheres) cohorts at a ratio of 7:3. Univariate logistic and least absolute shrinkage and selection operator regression analyses were used to identify the significant factors associated with good neoangiogenesis, which were used to develop a nomogram. The discrimination, calibration, and clinical utility were assessed. RESULTS: A total of 213 hemispheres in 126 patients were reviewed, including 152 (71.36%) hemispheres with good postoperative collateral formation and 61 (28.64%) with poor postoperative collateral formation. The authors selected 4 predictors (FGD5 rs11128722, VEGFA rs9472135, Suzuki stage, and internal carotid artery [ICA] moyamoya vessels) for nomogram development. The C-indices of the nomogram in the training and internal validation cohorts were 0.873 and 0.841, respectively. The nomogram exhibited a sensitivity of 84.5% and specificity of 81.0%. The positive and negative predictive values were 92.1% and 66.7%, respectively. The calibration curves indicated high predictive accuracy, and receiver operating characteristic curve analysis showed the superiority of the nomogram. The decision-making analysis validated the fitness and clinical application value of this nomogram. Then a web-based calculator to facilitate clinical application was generated. CONCLUSIONS: The nomogram developed in this study accurately predicted neoangiogenesis in patients with MMD and T2DM after EDAS and may assist neurosurgeons in identifying suitable candidates for indirect revascularization surgery.

Development and validation of a novel nomogram for predicting long-term rebleeding risk among patients with hemorrhagic moyamoya disease: a 10-year multicenter retrospective cohort study.

OBJECTIVE: The aim of this study was to develop and validate a predictive nomogram model for long-term rebleeding events in patients with hemorrhagic moyamoya disease (HMMD). METHODS: In total, 554 patients with HMMD from the Fifth Medical Center of the Chinese PLA General Hospital (5-PLAGH cohort) were included and randomly divided into training (390 patients) and internal validation (164 patients) sets. An independent cohort from the First Medical Center and Eighth Medical Center of Chinese PLA General Hospital (the 1-PLAGH and 8-PLAGH cohort) was used for external validation (133 patients). Univariate Cox regression analysis and least absolute shrinkage and selection operator (LASSO) regression algorithm were used to identify significant factors associated with rebleeding, which were used to develop a nomogram for predicting 5- and 10-year rebleeding. RESULTS: Intraventricular hemorrhage was the most common type of cerebral hemorrhage (39.0% of patients in the 5-PLAGH cohort and 42.9% of the 1-PLAGH and 8-PLAGH cohort). During the mean ± SD follow-up period of 10.4 ± 2.9 years, 91 (16.4%) patients had rebleeding events in the 5-PLAGH cohort. The rebleeding rates were 12.3% (68 patients) at 5 years and 14.8% (82 patients) at 10 years. Rebleeding events were observed in 72 patients (14.3%) in the encephaloduroarteriosynangiosis (EDAS) surgery group, whereas 19 patients (37.3%) experienced rebleeding events in the conservative treatment group. This difference was statistically significant (p < 0.001). We selected 4 predictors (age at onset, number of episodes of bleeding, posterior circulation involvement, and EDAS surgery) for nomogram development. The concordance index (C-index) values of the nomograms of the training cohort, internal validation cohort, and the external validation cohort were 0.767 (95% CI 0.704-0.830), 0.814 (95% CI 0.694-0.934), and 0.718 (95% CI 0.661-0.775), respectively. The nomogram at 5 years exhibited a sensitivity of 48.1% and specificity of 87.5%. The positive and negative predictive values were 38.2% and 91.3%, respectively. The nomogram at 10 years exhibited a sensitivity of 47.1% and specificity of 89.1%. The positive and negative predictive values were 48.5% and 88.5%, respectively. CONCLUSIONS: EDAS may prevent rebleeding events and improve long-term clinical outcomes in patients with HMMD. The nomogram accurately predicted rebleeding events and assisted clinicians in identifying high-risk patients and devising individual treatments. Simultaneously, comprehensive and ongoing monitoring should be implemented for specific patients with HMMD throughout their entire lifespan.

Clinical and genetic factors associated with contralateral progression in unilateral moyamoya disease: Longitudinal and Cross-Sectional Study.

Objective: This study aimed to explore the long-term outcome of unilateral moyamoya disease and predict the clinical and genetic factors associated with contralateral progression in unilateral moyamoya disease. Methods: We retrospectively recruited unilateral moyamoya disease patients with available genetic data who underwent encephaloduroarteriosynangiosis (EDAS) surgery at our institution from January 2009 to November 2017. Long-term follow-up data, including clinical outcomes, angiographic features, and genetic information, were analyzed. Results: A total of 83 unilateral moyamoya disease patients with available genetic data were enrolled in our study. The mean duration of clinical follow-up was 7.9 ± 2.0 years. Among all patients, 19 patients demonstrated contralateral progression to bilateral disease. Heterozygous Ring Finger Protein 213 p.R4810K mutations occurred significantly more frequently in unilateral moyamoya disease patients with contralateral progression. Furthermore, patients with contralateral progression typically demonstrated an earlier age of onset than those with non-progressing unilateral moyamoya disease. In the contralateral progression group, posterior circulation involvement was observed in 11 (11/19, 57.9%) patients compared to 12 (12/64, 18.8%) in the non-contralateral progression group (P = 0.001). The time to peak of cerebral perfusion and neurological status showed significant postoperative improvement. Conclusion: Long-term follow-up revealed that the EDAS procedure might provide benefits for unilateral moyamoya disease patients. Ring Finger Protein 213 p.R4810K mutations, younger age, and posterior circulation involvement might predict the contralateral progression of unilateral moyamoya disease.

Natural course and risk factors of moyamoya disease with unruptured intracranial aneurysm.

Background and objective: The natural course and risk factors of moyamoya disease (MMD) associated with unruptured intracranial aneurysms involving stenosed parental arteries are scarcely studied. This study aimed to elucidate the natural course of MMD and its associated risk factors in patients with MMD with unruptured aneurysms. Methods: Between September 2006 and October 2021, patients with MMD with intracranial aneurysms at our center were examined. The natural course, clinical features, radiological features, and follow-up outcomes after revascularization were analyzed. Results: This study included 42 patients with MMD with intracranial aneurysms (42 aneurysms). The age distribution of MMD cases ranged from 6 to 69 years, with four children (9.5%) and 38 adults (90.5%). A total of 17 male and 25 female subjects were included (male-to-female ratio: 1:1.47). The first symptom was cerebral ischemia in 28 cases, and cerebral hemorrhage occurred in 14 cases. There were 35 trunk aneurysms and seven peripheral aneurysms. There were 34 small aneurysms (<5 mm) and eight medium aneurysms (5-15 mm). During the average clinical follow-up period of 37.90 ± 32.53 months, there was no rupture or bleeding from aneurysms. Twenty-seven of these patients underwent a cerebral angiography review, in which it was found that one aneurysm had enlarged, 16 had remained unchanged, and 10 had shrunk or disappeared. A correlation exists between the reduction or disappearance of aneurysms and the progression of the Suzuki stages of MMD (P = 0.015). Nineteen patients underwent EDAS on the aneurysm side, and nine aneurysms disappeared, while eight patients did not undergo EDAS on the aneurysm side and one aneurysm disappeared. Conclusion: The risk of rupture and hemorrhage of unruptured intracranial aneurysms is low when the parent artery already has stenotic lesions, thus, direct intervention may not be necessary for such aneurysms. The progression of the Suzuki stage of moyamoya disease may play a role in the shrinkage or disappearance of the aneurysms, thereby decreasing the risk of rupture and hemorrhage. Encephaloduroarteriosynangiosis (EDAS) surgery may also help promote atrophy or even the disappearance of the aneurysm, thus reducing the risk of further rupture and bleeding.

The Impact of Palliative Care and Nursing Intervention on the Psychology and Quality of Life of Elderly Patients with Colorectal Cancer.

Colorectal cancer patients face physical, psychological, and social difficulties. Psychosocial therapies appear to be successful in improving cancer patients' psychological and social results. Preoperative and postoperative psychological therapies for colorectal surgery patients have not been extensively studied. During their treatment, up to 35% of cancer patients experience clinically severe psychological discomfort. As a consequence, a greater knowledge of health-related quality of life and its causes can assist oncology nurses in developing effective treatments to improve the health-related quality of life. The palliative care model and the nursing intervention model are used in this study to assess the effectiveness of an individually customized nursing intervention for lowering chemotherapy-related symptom distress in adult patients with colorectal cancer. Initially, the dataset is collected and split into the control group and the experimental group. The patient conditions are evaluated using the novel accelerated gradient boosting regression tree (AGBRT) estimation model. For improving the evaluation process, we have proposed the enriched gravitational search optimization algorithm (EGSOA). The system's success is evaluated in terms of the patients' psychological well-being and quality of life.

Nisin reduces uterine inflammation in rats by modulating concentrations of pro- and anti-inflammatory cytokines.

PROBLEM: The Staphylococcus aureus has been found to be associated with clinical endometritis of cow. The result of oral antibiotic remains poor. Therefore, this study investigates the role of nisin in endometritis. METHOD OF STUDY: The effect of nisin on the growth and cell wall of S aureus were determined in vitro. Besides the blank control group, animals with established post-partum were inoculated with 0.1 mL S aureus intravaginally. Two days post-inoculation, the animals were administered nisin (25 mg/kg), kanamycin (30 mg/kg), and water (model group) for 7 days. On the seventh day, serum and uterine organs were obtained for pro- and anti-inflammatory analysis. The uterine tissue samples were weighed, and histopathological analysis was performed. RESULTS: The results showed that nisin had an inhibitory effect on the growth and cell wall formation of S aureus. Nisin and kanamycin treatment prevented a S aureus-induced decrease in pro-inflammatory cytokines and promoted an increase in the level of serum anti-inflammatory cytokines in the endometrium of these animals. Nisin and kanamycin, significantly decreased (P < 0.05) the endometritis-induced increases in uterine weight, restored endometrial architecture and significantly (P < 0.05) normalized uterine neutrophils to control levels. Additionally, improved levels of B7-2 , IFN-γ, IL-2, and IL-8 were observed when treated with nisin. CONCLUSION: Our findings suggest that nisin compared favorably with kanamycin in endometritis prevention, suggesting that nisin can be used in S aureus-induced endometritis by protecting the uterus from S aureus infection.

Lack of Adipocytes Alters Hematopoiesis in Lipodystrophic Mice.

Adult hematopoiesis takes place in the perivascular zone of the bone cavity, where endothelial cells, mesenchymal stromal/stem cells and their derivatives such as osteoblasts are key components of bone marrow (BM) niches. Defining the contribution of BM adipocytes to the hematopoietic stem cell niche remains controversial. While an excess of medullar adiposity is generally considered deleterious for hematopoiesis, an active role for adipocytes in shaping the niche has also been proposed. We thus investigated the consequences of total adipocyte deletion, including in the BM niche, on adult hematopoiesis using mice carrying a constitutive deletion of the gene coding for the nuclear receptor peroxisome proliferator-activated receptor-γ (PPARγ). We show that PpargΔ/Δ lipodystrophic mice exhibit severe extramedullary hematopoiesis (EMH), which we found to be non-cell autonomous, as it is reproduced when wild-type donor BM cells are transferred into PpargΔ/Δ recipients. This phenotype is not due to a specific alteration linked to Pparg deletion, such as chronic inflammation, since it is also found in AZIPtg/+ mice, another lipodystrophic mouse model with normal PPARγ expression, that display only very moderate levels of inflammation. In both models, the lack of adipocytes alters subpopulations of both myeloid and lymphoid cells. The CXCL12/CXCR4 axis in the BM is also dysregulated in an adipocyte deprived environment supporting the hypothesis that adipocytes are required for normal hematopoietic stem cell mobilization or retention. Altogether, these data suggest an important role for adipocytes, and possibly for the molecular interactions they provide within the BM, in maintaining the appropriate microenvironment for hematopoietic homeostasis.

Mutations in Fibronectin Cause a Subtype of Spondylometaphyseal Dysplasia with "Corner Fractures".

Fibronectin is a master organizer of extracellular matrices (ECMs) and promotes the assembly of collagens, fibrillin-1, and other proteins. It is also known to play roles in skeletal tissues through its secretion by osteoblasts, chondrocytes, and mesenchymal cells. Spondylometaphyseal dysplasias (SMDs) comprise a diverse group of skeletal dysplasias and often manifest as short stature, growth-plate irregularities, and vertebral anomalies, such as scoliosis. By comparing the exomes of individuals with SMD with the radiographic appearance of "corner fractures" at metaphyses, we identified three individuals with fibronectin (FN1) variants affecting highly conserved residues. Furthermore, using matching tools and the SkelDys emailing list, we identified other individuals with de novo FN1 variants and a similar phenotype. The severe scoliosis in most individuals and rare developmental coxa vara distinguish individuals with FN1 mutations from those with classical Sutcliffe-type SMD. To study functional consequences of these FN1 mutations on the protein level, we introduced three disease-associated missense variants (p.Cys87Phe [c.260G>T], p.Tyr240Asp [c.718T>G], and p.Cys260Gly [c.778T>G]) into a recombinant secreted N-terminal 70 kDa fragment (rF70K) and the full-length fibronectin (rFN). The wild-type rF70K and rFN were secreted into the culture medium, whereas all mutant proteins were either not secreted or secreted at significantly lower amounts. Immunofluorescence analysis demonstrated increased intracellular retention of the mutant proteins. In summary, FN1 mutations that cause defective fibronectin secretion are found in SMD, and we thus provide additional evidence for a critical function of fibronectin in cartilage and bone.

The spectrum of infantile myofibromatosis includes both non-penetrance and adult recurrence.

Infantile myofibromatosis is characterized by benign myofibroblastic tumors within skin, muscle, bone or viscera which have a characteristic staining pattern on immunohistochemistry. The condition typically presents in infancy and the tumors often disappear by the third year of life. Mutations in the PDGFRB gene and NOTCH3 genes have been identified in familial forms of the condition. We present two families with molecularly confirmed germline mutations in the PDGFRB gene, one demonstrating a phenotype ranging from complete non-penetrance to neonatal lethality; and the other illustrating adult recurrence of the tumors.

Mutations in the Chromatin Regulator Gene BRPF1 Cause Syndromic Intellectual Disability and Deficient Histone Acetylation.

Identification of over 500 epigenetic regulators in humans raises an interesting question regarding how chromatin dysregulation contributes to different diseases. Bromodomain and PHD finger-containing protein 1 (BRPF1) is a multivalent chromatin regulator possessing three histone-binding domains, one non-specific DNA-binding module, and several motifs for interacting with and activating three lysine acetyltransferases. Genetic analyses of fish brpf1 and mouse Brpf1 have uncovered an important role in skeletal, hematopoietic, and brain development, but it remains unclear how BRPF1 is linked to human development and disease. Here, we describe an intellectual disability disorder in ten individuals with inherited or de novo monoallelic BRPF1 mutations. Symptoms include infantile hypotonia, global developmental delay, intellectual disability, expressive language impairment, and facial dysmorphisms. Central nervous system and spinal abnormalities are also seen in some individuals. These clinical features overlap with but are not identical to those reported for persons with KAT6A or KAT6B mutations, suggesting that BRPF1 targets these two acetyltransferases and additional partners in humans. Functional assays showed that the resulting BRPF1 variants are pathogenic and impair acetylation of histone H3 at lysine 23, an abundant but poorly characterized epigenetic mark. We also found a similar deficiency in different lines of Brpf1-knockout mice. These data indicate that aberrations in the chromatin regulator gene BRPF1 cause histone H3 acetylation deficiency and a previously unrecognized intellectual disability syndrome.

PPARß/δ governs Wnt signaling and bone turnover.

Peroxisome proliferator-activated receptors (PPARs) act as metabolic sensors and central regulators of fat and glucose homeostasis. Furthermore, PPARγ has been implicated as major catabolic regulator of bone mass in mice and humans. However, a potential involvement of other PPAR subtypes in the regulation of bone homeostasis has remained elusive. Here we report a previously unrecognized role of PPARß/δ as a key regulator of bone turnover and the crosstalk between osteoblasts and osteoclasts. In contrast to activation of PPARγ, activation of PPARß/δ amplified Wnt-dependent and ß-catenin-dependent signaling and gene expression in osteoblasts, resulting in increased expression of osteoprotegerin (OPG) and attenuation of osteoblast-mediated osteoclastogenesis. Accordingly, PPARß/δ-deficient mice had lower Wnt signaling activity, lower serum concentrations of OPG, higher numbers of osteoclasts and osteopenia. Pharmacological activation of PPARß/δ in a mouse model of postmenopausal osteoporosis led to normalization of the altered ratio of tumor necrosis factor superfamily, member 11 (RANKL, also called TNFSF11) to OPG, a rebalancing of bone turnover and the restoration of normal bone density. Our findings identify PPARß/δ as a promising target for an alternative approach in the treatment of osteoporosis and related diseases.

[L-arginine suppresses ischemia/reperfusion induced up-regulation of endothelin-1 production in a rat model of acute myocardial injury].

OBJECTIVE: To examine the level of endothelin-1 (ET-1) in serum and its expression in myocardium tissue during the development of acute myocardial ischemia/reperfusion (I/R) injury in rat and the effects of L-arginine (L-Arg) administration on these indexes. METHODS: One hundred and ten Wistar rats were randomly divided into nine groups to receive: (1) sham surgery, (2)ischemia (I, by ligation of anterior descending coronary artery for 30 minutes), (3) I+reperfusion (R, by the removal of the ligature) for 0.5 hour, (4) I+R for 1 hour, (5) I+R for 2 hours; group (6) ~ (9) also received I/R treatment as in group 2 ~ 5 respectively but with L-Arg pretreatment. Blood and myocardium tissue samples were collected by the end of the experiment for the analysis of: serum level of creatine kinase (CK), lactate dehydrogenase [LDH, by enzyme linked immunosorbent assay (ELISA)], ET-1 (radioimmunoassay), and the tissue content of ET-1 mRNA/peptide [by reverse-transcription polymerase chain-reaction (RT-PCR) and Western blotting]. RESULTS: In comparison with the sham treated control animals, the serum levels of CK, LDH, and ET-1 were all significantly higher in the groups treated with I/R (particularly those exposed to reperfusion). The myocardial tissue content of ET-1 mRNA/peptide were also significantly increased in I/R treated groups (particularly the I+R 2 hours group) as compared to control (ET-1 mRNA: 0.775 ± 0.029 vs. 0.310 ± 0.076; ET-1 peptide: 0.773 ± 0.055 vs. 0.340 ± 0.099, both P < 0.05). The i.v. administration of L-Arg significantly suppressed the up-regulation of tissue content of ET-1 mRNA /peptide in I/R treated animals (ET-1 mRNA: 0.340 ± 0.049 vs. 0.775 ± 0.029; ET-1 peptide: 0.390 ± 0.094 vs. 0.773 ± 0.055, both P < 0.05). CONCLUSION: L-Arg may be tested during certain stage of I/R injury as a therapeutic intervention for the suppression of ET-1 up-regulation.

TGF-beta1 in serum and induced sputum for predicting radiation pneumonitis in patients with non-small cell lung cancer after radiotherapy.

BACKGROUND AND OBJECTIVE: Research has confirmed that transforming growth factor-beta1 (TGF-beta1) is one of the cytokines related to radiation pneumonitis. But the level of TGF-beta1 in serum needed to predict radiation pneumonitis is still not clear. This study assessed the value of TGF-beta1 in both serum and induced sputum in predicting radiation pneumonitis, providing a reference for the radiotherapy of patients with non-small cell lung cancer (NSCLC). METHODS: A total of 23 patients with NSCLC treated with three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiation therapy (IMRT) in our department between November 2007 and January 2009 were analyzed and evaluated. TGF-beta1 levels in both serum and sputum were detected before and near the end of radiotherapy for all the patients. The TGF-beta1 level in serum was measured with enzyme-linked immunosorbent assay (ELISA). Immunocytochemistry assays were used to detect TGF-beta1 expression in sputum sediment. Radiation pneumonitis was graded according to Radiation Therapy Oncology Group (RTOG) radiation scoring criteria every 3 weeks from the start to 3 months after the end of treatment. RESULTS: Radiation pneumonitis was noted in 9 patients in this cohort. The total incidence of radiation pneumonitis was 39.1% (9/23) and those with Grade II or worse was 30.4% (7/23). The absolute TGF-beta1 level in serum after radiotherapy was higher than before radiotherapy, but there was no statistical difference (P = 0.139). Patients with increased levels of TGF-beta1 had a higher incidence of radiation pneumonitis (45.5%) than those with decreased TGF-beta1 levels post-radiotherapy (40.0%). Though there was a tendency of higher incidence of radiation pneumonitis with increases in TGF-beta1 level, no statistical difference was found (P = 1.000). Patients with tumor response had higher incidence of radiation pneumonitis (50.0%) than patients without when TGF-beta1 levels in serum increased, but there was no statistical difference (P = 0.792). TGF-beta1 was positively expressed (brown yellow) in sputum on immunocytochemistry assays and located in the cytoplasm of either macrophages or epithelial cells. Macrophages were the main cells expressing TGF-beta1. A significantly higher positive expression rate (71.4%) was found in sputum post-radiotherapy than pre-radiotherapy (28.6%) (P = 0.015). The higher incidence of radiation pneumonitis (46.7%) was found in patients with positive TGF-beta1 expression in sputum post-radiotherapy than those with negative expression post-radiotherapy (14.3%) (P = 0.193). CONCLUSION: It may be more reasonable to predict radiation pneumonitis by combining the change of TGF-beta1 levels in serum with tumor response than just the change of TGF-beta1 levels in serum alone. TGF-beta1 can positively express in the sputum of patients with NSCLC, located in macrophages and epithelial cells, with macrophages as the main areas of expression. Patients with positively expressed TGF-beta1 in sputum after radiotherapy have a higher incidence of radiation pneumonitis than those with negative expressions. The positive expression of TGF-beta1 in sputum is expected to become a factor for predicting radiation pneumonitis.

Surface segregation of Si and its effect on oxygen adsorption on a γ-TiAl(111) surface from first principles.

We perform first-principles calculations based on the density-functional theory to study the surface segregation of Si and its effect on the oxygen adsorption on a γ-TiAl(111) surface for a range of oxygen coverage 0<Θ≤1.0 monolayer (ML). The calculated results show that the alloying Si atoms prefer occupying surface Ti sites to the sites in the bulk of γ-TiAl, which suggests the occurrence of Si surface segregation. When oxygen atoms adsorb on a pure γ-TiAl(111) surface, the most favorable sites are the adsorption sites with more Ti atoms as their nearest neighbors in the surface layer at all the calculated coverages and the interactions between adsorbed oxygen atoms are repulsive. However, when oxygen atoms adsorb on an Si-alloyed γ-TiAl(111) surface, the interactions between the adsorbed oxygen atoms are attractive at oxygen coverage 0<Θ≤1.0 ML. Meanwhile, the interactions between O and Al atoms become stronger whereas those between O and Ti atoms become weaker relative to oxygen adsorbed on a pure γ-TiAl(111) surface. The atomic geometry and density of state are analyzed. The results show that the surface ripple of the top metal layer for oxygen on a pure γ-TiAl(111) surface is Ti upwards, while that for oxygen on an Si-alloyed γ-TiAl(111) surface is Al upwards at high oxygen coverage (Θ≥0.50 ML). This effect of Si is of benefit to the nucleation of alumina, which is attributed to Si surface segregation and an increase of the surface Al:Ti ratio. This can help to explain why alloying the γ-TiAl(111) surface with Si could favor the formation of the Al(2)O(3) scale at the first stage and result in good oxidation resistance in experiments.

[Detection of regional lymph node micrometastasis and its impact on long-term survival of non-small cell lung cancer (NSCLC) patients].

BACKGROUND & OBJECTIVE: Regional lymph node micrometastasis, which can not be found by routine pathologic examination, may be detected by immunohistochemistry after radical operation of tumors. This study was to investigate regional lymph node micrometastasis in non-small cell lung cancer (NSCLC) and its impact on prognosis. METHODS: The expressions of cytokeratin (CK) in 684 specimens from 78 stage pT1-2N0M0 NSCLC patients, treated from Jan. 1996 to Dec. 2003, were detected by EnVision method using anti-CK antibody AE1/AE3. The correlation of CK expression to prognosis was analyzed. RESULTS: The overall detection rate of CK was 26.9%û the detection rates were 5.9% in stage p-IA patients and 32.8% in stage p-IB patients. The 1-, 3-, 5-, and 8-year survival rates were significantly higher in non-micrometastasis group than in micrometastasis group (90.80% vs. 60.00%, 69.70% vs. 48.48%, 55.76% vs. 29.09%, and 37.17% vs. 0, P=0.008)û the median survival time were 87 months and 23 months, respectively. CK and KPS score were independent prognostic factors of NSCLC (P=0.014, P<0.001). Compared with surgery alone, surgery plus postoperative radiochemotherapy prolonged survival, but the difference was not significant (P=0.063). CONCLUSIONS: The detection rate of lymph node micrometastases may be increased with the progression of NSCLC. Micrometastasis is an independent prognostic factor of NSCLC.