The effect of integrative Korean medicine treatment on symptomatic lumbar facet joint cysts: A case series.

OBJECTIVE: The optimal treatment for facet joint cysts (FJCs) has remained controversial. Despite a higher success rate than the conservative option, surgical treatments may pose risks of postoperative complications and comorbidities may make the surgical approach difficult. Thus, this study reports four cases of pain amelioration and resorption of FJCs through noninvasive integrative Korean Medicine treatment. METHODS: For intervention, four patients with symptomatic FJCs underwent integrative Korean medicine treatment with acupuncture, herbal medicine, pharmacopuncture, and Chuna manual therapy; after completion of the series of treatment sessions, patients were re-examined with magnetic resonance imaging (MRI). RESULTS: Pain disappeared within 2 months for all four patients; the amelioration of pain was sustained for more than 6 months. Furthermore, the disappearance of FJCs was confirmed by MRI after a certain period from the time of pain disappearance. CONCLUSIONS: This study reported the effectiveness of non-invasive, integrative Korean medicine treatment for patients with FJCs; this method shows promise as a conservative treatment option for patients with FJCs.

COG-imposed Golgi functional integrity determines the onset of dark-induced senescence.

Plant survival depends on dynamic stress-response pathways in changing environments. To uncover pathway components, we screened an ethyl methanesulfonate-mutagenized transgenic line containing a stress-inducible luciferase construct and isolated a constitutive expression mutant. The mutant is the result of an amino acid substitution in the seventh subunit of the hetero-octameric conserved oligomeric Golgi (COG) complex of Arabidopsis thaliana. Complementation studies verified the Golgi localization of cog7, and stress tests established accelerated dark-induced carbon deprivation/senescence of the mutant compared with wild-type plants. Multiomics and biochemical analyses revealed accelerated induction of protein ubiquitination and autophagy, and a counterintuitive increased protein N-glycosylation in senescencing cog7 relative to wild-type. A revertant screen using the overexpressor (FOX)-hunting system established partial, but notable rescue of cog7 phenotypes by COG5 overexpression, and conversely premature senescence in reduced COG5 expressing lines. These findings identify COG-imposed Golgi functional integrity as a main player in ensuring cellular survival under energy-limiting conditions.

Pain, disability, and MRI changes in lumbar disc herniation patients treated with integrative medicine: Ten-year results of an observational study.

BACKGROUND: To date, a 10-year follow-up study on complementary and alternative medical treatment of lumbar intervertebral disc herniation (LDH) has never been conducted. Therefore, we aimed to perform a prospective 10-year follow-up study on the integrated treatment of LDH in Korea. METHODS: One hundred and fifty patients from the baseline study, who initially met the LDH diagnostic criteria with a chief complaint of radiating pain and received integrated treatment, were recruited for this follow-up study. The 10-year follow-up was conducted from February 2018 to March 2018 on pain, disability, satisfaction, quality of life, and changes in herniated disc, muscles, and fat through magnetic resonance imaging. RESULTS: Sixty-five patients were included in this follow-up study. Visual analogue scale score for lower back pain and radiating leg pain were maintained at a significantly lower level than the baseline level. Significant improvements in Oswestry disability index and quality of life were consistently present. MRI confirmed that disc herniation size was reduced over the 10-year follow-up. In total, 95.38% of the patients were either "satisfied" or "extremely satisfied" with the treatment outcomes and 89.23% of the patients claimed their condition "improved" or "highly improved" at the 10-year follow-up. CONCLUSIONS: The reduced pain and improved disability was maintained over 10 years in patients with LDH who were treated with nonsurgical Korean medical treatment 10 years ago. Nonsurgical traditional Korean medical treatment for LDH produced beneficial long-term effects, but future large-scale randomized controlled trials for LDH are needed. STUDY REGISTRATION: ClinicalTrials.gov, NCT03426215.

Prescription rate and treatment patterns for allergic rhinitis from 2010 to 2018 in South Korea: a retrospective study.

BACKGROUND: There has been little investigation on how guidelines for allergic rhinitis (AR) treatment are applied in current clinical practice. We aimed to analyze prescription trends and patterns for AR treatment according to patient characteristics over a 9-year period in Korea. METHODS: We used cross-sectional data from the Korean Health Insurance Review & Assessment Service National Patient Sample from 2010 to 2018. We analyzed 1,719,194 patients with AR as the principal diagnosis. Prescription rates of antihistamines, steroids, and other drugs; combination prescriptions; and first-choice prescriptions were analyzed. RESULTS: The prescription rate of first-generation antihistamines decreased over the years (2010: 29.13; 2018: 23.41). By contrast, the prescription rate of systemic steroids (2010: 23.60; 2018: 28.70), nasal steroids (2010: 9.70; 2018: 14.67), and leukotriene receptor antagonists (LTRAs) (2010: 11.13; 2018: 26.56) increased. The prescription rate of steroids was lower in patients aged 0-5 years and ≥ 65 years than in other age groups and that of LTRAs was the highest in patients aged 0-5 years. The rate of combination prescribing antihistamines and nasal steroids increased (2010: 7.99; 2018: 12.09). The rate of first-choice prescriptions with antihistamines and nasal steroids also increased (2010: 4.72; 2018: 7.24). CONCLUSIONS: The results confirmed a decrease in antihistamine prescriptions, especially with first-generation, and an increase in steroid and LTRA prescriptions in patients with AR in Korea. Regarding prescription patterns, steroids were increasingly prescribed in combination with antihistamines. However, the trend was opposite in the 0-5 years and ≥ 65 years groups.

The DME demethylase regulates sporophyte gene expression, cell proliferation, differentiation, and meristem resurrection.

The flowering plant life cycle consists of alternating haploid (gametophyte) and diploid (sporophyte) generations, where the sporophytic generation begins with fertilization of haploid gametes. In Arabidopsis, genome-wide DNA demethylation is required for normal development, catalyzed by the DEMETER (DME) DNA demethylase in the gamete companion cells of male and female gametophytes. In the sporophyte, postembryonic growth and development are largely dependent on the activity of numerous stem cell niches, or meristems. Analyzing Arabidopsis plants homozygous for a loss-of-function dme-2 allele, we show that DME influences many aspects of sporophytic growth and development. dme-2 mutants exhibited delayed seed germination, variable root hair growth, aberrant cellular proliferation and differentiation followed by enhanced de novo shoot formation, dysregulation of root quiescence and stomatal precursor cells, and inflorescence meristem (IM) resurrection. We also show that sporophytic DME activity exerts a profound effect on the transcriptome of developing Arabidopsis plants, including discrete groups of regulatory genes that are misregulated in dme-2 mutant tissues, allowing us to potentially link phenotypes to changes in specific gene expression pathways. These results show that DME plays a key role in sporophytic development and suggest that DME-mediated active DNA demethylation may be involved in the maintenance of stem cell activities during the sporophytic life cycle in Arabidopsis.

Survey of Integrative Treatment Practices of Korean Medicine Doctors for Cervical Disc Herniation: Preliminary Data for Clinical Practice Guidelines.

A survey study was conducted in Korean medicine doctors who provide nonsurgical integrative treatment for cervical disc herniation (CDH) at spine-specialty hospitals to assess usual treatment practices, diagnosis and treatment methods, and related adverse events for CDH. The questionnaire was jointly developed by clinical experts and methodology experts and was administered to 197 Korean medicine doctors (response rate: 84.9% (n = 197/232)) practicing at spine-specialty Korean medicine hospitals for analysis of general sociodemographic information, practice patterns of CDH including diagnosis and treatment strategies, CDH prognosis, and treatment safety. The average clinical experience of respondents was 9.3±6.4 years, and 4.0±1.8 weeks were regarded to be needed for CDH pain to decrease by 50% and 9.1±3.4 weeks to decrease by 80%. Eight-Principle Pattern and Meridian System Identification were the most commonly used Korean medicine syndrome differentiation methods, and CDH was most often considered to be a result of Qi stagnation and Blood coagulation. The Spurling test was reported to be important in physical examination, and magnetic resonance (MR) images were mostly used for diagnosis and treatment of CDH of various diagnostic tools. Treatment mainly consisted of a nonsurgical, integrative multimodal approach comprising acupuncture, pharmacopuncture, herbal medicine, and Chuna manual therapy. Shinbaro pharmacopuncture and Chungpa-jun, which are well-established herbal treatments supported by evidence, were considered to be of high importance in CDH treatment. With regard to safety, acupuncture was considered to be the safest, while bee venom pharmacopuncture was of highest concern due to potential hypersensitivity. This study is the first report to investigate current practice patterns and approach of Korean medicine doctors to CDH treatment. This data may be of significance to Korean medicine doctors in drawing clinical guidelines and conducting randomized controlled trials (RCTs) to generate high-level evidence on the effectiveness of nonsurgical integrative medicine treatments for CDH.

Root hairs enhance Arabidopsis seedling survival upon soil disruption.

Root hairs form a substantial portion of the root surface area. Compared with their nutritional function, the physical function of root hairs has been poorly characterised. This study investigates the physical role of root hairs of Arabidopsis thaliana seedlings in interaction of the root with water and soil and in plant survival upon soil disruption. Five transgenic lines with different root hair lengths were used to assess the physical function of root hairs. Upon soil disruption by water falling from a height (mimicking rainfall), long-haired lines showed much higher anchorage rates than short-haired lines. The root-pulling test revealed that a greater amount of soil adhered to long-haired roots than to short-haired roots. When seedlings were pulled out and laid on the soil surface for 15 d, survival rates of long-haired seedlings were higher than those of short-haired seedlings. Moreover, the water holding capacity of roots was much greater among long-haired seedlings than short-haired seedlings. These results suggest that root hairs play a significant role in plant survival upon soil disruption which could be fatal for young seedlings growing on thin soil surface with a short primary root and root hairs as the only soil anchoring system.

Nonsurgical integrative Korean Medicine treatment of discal cyst: A case report and a retrospective chart review analysis.

RATIONALE: Discal cysts are rare lesions characterized by pain caused by neurogenic compression with similar symptoms as those of disc herniation. This study aims to report the spontaneous regression of discal cyst achieved through nonsurgical integrative Korean Medicine treatment and the clinical epidemiological features of discal cyst cases collected from 4 institutions. PATIENT CONCERNS: A 31-year-old woman had low back pain and radiating pain equivalent to a numeral rating scale (NRS) of 8 and had limitations in daily work and activities. DIAGNOSES: The patient was diagnosed as having discal cysts that compressed the left S1 based on findings of L-spine magnetic resonance imaging (MRI) performed at our hospital. INTERVENTIONS: The patient received nonsurgical Korean Medicine treatment and after 24 days of treatment in the hospital, she underwent 16 additional treatments as an outpatient. OUTCOMES: Spontaneous regression was confirmed in the L-spine MRI follow-up at 36 days and 99 days after the initial test, and the patient underwent once-a-week follow up to examine NRS, Oswestry Disability Index (ODI), EuroQol-5 Dimensions (EQ-5D), and fear-avoidance beliefs questionnaire (FABQ) after 4 weeks, and 2, 3, and 6-month follow-ups after that. The patient was discharged in a painless condition, and she was able to carry on for 5 months without increased pain. LESSONS: Discal cysts are more rapid progress than disc herniation, it seems valid to attempt nonsurgical treatment. Epidemiologically, this is the first study to present the clinical epidemiological characteristics of discal cysts, it would provide valuable information to clinicians who treat and study discal cysts.

Clinical application of 3D technology for tooth autotransplantation: A case report.

This report presents two cases of tooth autotransplantation using cone-beam computed tomography (CBCT), the three-dimensional (3D) simulation dental planning software and a computer-aided rapid prototyping (CARP) model. Two hopeless teeth of adult patients were replaced as their third molar teeth. Before deciding the autotransplantation, diagnostic CBCT images were acquired and imported to SimPlant software. The SimPlant dental program was used for surgical simulation prior to autotransplantation, which created 3D images of the available donor teeth and recipient site tooth and superimposed the images to display their morphological similarity. Efficient modification of the recipient socket was designed preoperatively. The CARP model of the donor tooth was prepared as a substitute for the donor tooth that would be fit into the new recipient socket during bone preparation. Autotransplantation was favourably performed in 5-6 min. Transplanted teeth healed up without clinical abnormality. The postoperative follow-up time was up to 6 years.

Two TPL-Binding Motifs of ARF2 Are Involved in Repression of Auxin Responses.

Auxin signaling is finalized by activator auxin response factors (aARFs) that are released from Auxin/Indole-3-Acetic Acid (Aux/IAA) repressors and directly activate auxin-responsive genes. However, it remains to be answered how repressor ARFs (rARFs) exert their repression function. In this study, we assessed the molecular and biological functions of two putative co-repressor-binding motifs (EAR and RLFGI) of ARF2 (a rARF) in Arabidopsis thaliana. In the yeast two-hybrid assay, the EAR mutation moderately and the RLFGI mutation, or both motifs, almost completely disrupted the interaction between the co-repressor TOPLESS (TPL) and the repressive motifs-containing middle domain (MD) of ARF2. The ARF2-MD interacted not only with TPL but also with TPL homologs (TPRs). Root hair-specific overexpression of rARFs (ARF1-4, 9-11, and 16) considerably inhibited root hair growth, suggesting that rARFs generally function as repressors in the auxin-responsive root hair single cell. Individual mutation of the ARF2 EAR or RLFGI motif slightly and both mutations greatly compromised ARF2-mediated inhibition of root hair growth and auxin-responsive gene expression. In addition, flowering time and seed size, two representative arf2 mutant phenotypes, were examined to assess the function of the repressive motifs in mutant-complementation experiments. ARF2-mediated inhibition of flowering and seed growth was suppressed considerably by the individual mutation of EAR or RLFGI and almost completely by both mutations. These results suggest that EAR and RLFGI work together as major repressive motifs for ARF2 to recruit TPL/TPR co-repressors and to exhibit its repressive biological functions.

Molecular link between auxin and ROS-mediated polar growth.

Root hair polar growth is endogenously controlled by auxin and sustained by oscillating levels of reactive oxygen species (ROS). These cells extend several hundred-fold their original size toward signals important for plant survival. Although their final cell size is of fundamental importance, the molecular mechanisms that control it remain largely unknown. Here we show that ROS production is controlled by the transcription factor RSL4, which in turn is transcriptionally regulated by auxin through several auxin response factors (ARFs). In this manner, auxin controls ROS-mediated polar growth by activating RSL4, which then up-regulates the expression of genes encoding NADPH oxidases (also known as RESPIRATORY BURST OXIDASE HOMOLOG proteins) and class III peroxidases, which catalyze ROS production. Chemical or genetic interference with ROS balance or peroxidase activity affects root hair final cell size. Overall, our findings establish a molecular link between auxin and ROS-mediated polar root hair growth.

Tracheophytes Contain Conserved Orthologs of a Basic Helix-Loop-Helix Transcription Factor That Modulate ROOT HAIR SPECIFIC Genes.

ROOT HAIR SPECIFIC (RHS) genes, which contain the root hair-specific cis-element (RHE) in their regulatory regions, function in root hair morphogenesis. Here, we demonstrate that an Arabidopsis thaliana basic helix-loop-helix transcription factor, ROOT HAIR DEFECTVE SIX-LIKE4 (RSL4), directly binds to the RHE in vitro and in vivo, upregulates RHS genes, and stimulates root hair formation in Arabidopsis. Orthologs of RSL4 from a eudicot (poplar [Populus trichocarpa]), a monocot (rice [Oryza sativa]), and a lycophyte (Selaginella moellendorffii) each restored root hair growth in the Arabidopsis rsl4 mutant. In addition, the rice and S. moellendorffii RSL4 orthologs bound to the RHE in in vitro and in vivo assays. The RSL4 orthologous genes contain RHEs in their promoter regions, and RSL4 was able to bind to its own RHEs in vivo and amplify its own expression. This process likely provides a positive feedback loop for sustainable root hair growth. When RSL4 and its orthologs were expressed in cells in non-root-hair positions, they induced ectopic root hair growth, indicating that these genes are sufficient to specify root hair formation. Our results suggest that RSL4 mediates root hair formation by regulating RHS genes and that this mechanism is conserved throughout the tracheophyte (vascular plant) lineage.

The optimal serum pepsinogen cut-off value for predicting histologically confirmed atrophic gastritis.

BACKGROUND: Although serum pepsinogen tests are useful for predicting the presence of atrophic gastritis, the optimal cut-off values have not been fully evaluated. AIM: To determine the optimal serum pepsinogen cut-off value for predicting atrophic gastritis. METHODS: Patients scheduled for upper endoscopy at Severance Hospital, Korea, between August 2012 and October 2013, were recruited prospectively. Endoscopic biopsies for atrophic gastritis were obtained and histologically graded, based on the updated Sydney system. RESULTS: Ninety-five patients were enrolled in the study. The mean age was 57.7±12.1 years, and 44.2% of the patients were male. Serum pepsinogen I/II ratios were lower in patients with atrophic gastritis than in those without it (antrum, 4.2±1.7 vs. 5.2±2.1, P=0.040; corpus, 3.3±1.9 vs. 5.4±1.9, P<0.001). Serum pepsinogen I/II ratios were significantly correlated with histologic atrophic gastritis (antrum, P=0.030; corpus, P<0.001). Using a cut-off value of 4.9, the sensitivity and specificity of the serum pepsinogen I/II ratio for predicting atrophic gastritis in the antrum were 68.2% and 60.3%, respectively. CONCLUSION: The optimal serum pepsinogen I/II ratio cut-off values for atrophic gastritis of the antrum and for the corpus were 4.9 and 3.5, respectively. Serum pepsinogen I/II ratios, with these cut-off values, are useful for screening patients for the presence of atrophic gastritis.

Autophagy is related to the hedgehog signaling pathway in human gastric adenocarcinoma: prognostic significance of Beclin-1 and Gli2 expression in human gastric adenocarcinoma.

Beclin-1 induces autophagy, which is known to be involved in many physiopathological processes such as cell development, aging, stress response, immune response and cancer. Several studies showed that Beclin-1 expression is associated with several prognostic factors of gastric carcinomas. Recently, the connection between autophagy and the hedgehog (HH) signaling pathway has been studied. Here, we investigated the relationship between the autophagy and hedgehog (HH) signaling pathways in gastric adenocarcinoma. We evaluated Beclin-1 and Gli2 expression in 108 gastric adenocarcinoma tissues via immunohistochemical analysis, using a tissue microarray, in relation to survival and other prognostic factors. Our results show that increased Beclin-1 expression is correlated with favorable clinicopathological variables including histologic grade, tumor size, primary tumor (T) stage, lymph node metastasis, lymphatic invasion, neural invasion, and tumor recurrence. Furthermore, increased Gli-2 expression was correlated with several favorable clinicopathological variables including primary tumor (T) stage, lymphatic invasion, and tumor recurrence. Increased Beclin-1 expression was significantly correlated with increased Gli2. Univariate analyses for disease-free survival and overall survival revealed that the higher Beclin-1 and Gli2 expression group had a more favorable prognosis compared with the lower Beclin-1 and Gli2 expression group. Our results suggest that progressively increased Beclin-1 and Gli2 expression contributes to the inhibition of tumor growth and metastasis in gastric adenocarcinoma and Beclin-1 acts as a tumor suppressor by regulating the HH signaling pathway through Gli2 expression in gastric adenocarcinoma.

Demographic characteristics and medical service use of failed back surgery syndrome patients at an integrated treatment hospital focusing on complementary and alternative medicine: a retrospective review of electronic medical records.

Objective. To report the patient demographics and nonsurgical complementary and alternative medicine treatment used at a Korean medicine hospital for low back pain (LBP) and/or sciatica after surgery. Methods. Medical records of patients who visited a spine-specialized Korean medicine hospital at 2 separate sites for continuous or recurrent LBP or sciatica following back surgery were reviewed. The demographics, MRI and/or CT scans, and treatments were assessed. Results. Of the total 707 patients, 62% were male and the average age was 50.20 years. Ninety percent of patients presented with LBP and 67% with sciatica. Eighty-four percent were diagnosed with herniated nucleus pulposus at time of surgery. Of these patients, 70% had pain recurrence 6 months or later, but 19% experienced no relief or immediate aggravation of pain after surgery. Many patients selected traditional Korean medicine treatment as primary means of postsurgery care (47%). When time to pain recurrence was short or pain persisted after surgery, return of symptoms at the same disc level and side was frequent. Conclusion. An integrative treatment model focusing on Korean medicine and used in conjunction with radiological diagnostics and conventional medicine is currently used as a treatment option for patients with pain after lumbar spine surgery.

Primary myxoid leiomyoma of the liver.

Herein, we report a case of primary myxoid leiomyoma of the liver. A 60-year-old woman complained of upper abdominal fullness. Computed tomography showed a solid tumor (8 cm) in the liver. The patient underwent right hepatectomy and histological findings from the resected specimen revealed scattered bland spindle cells in a background of exuberant myxoid material. The tumor cells were immunoreactive for smooth muscle actin and desmin. No other lesions were found elsewhere in the body. Thus, the tumor was diagnosed as a primary myxoid leiomyoma of the liver.

Genome sequence of the hot pepper provides insights into the evolution of pungency in Capsicum species.

Hot pepper (Capsicum annuum), one of the oldest domesticated crops in the Americas, is the most widely grown spice crop in the world. We report whole-genome sequencing and assembly of the hot pepper (Mexican landrace of Capsicum annuum cv. CM334) at 186.6× coverage. We also report resequencing of two cultivated peppers and de novo sequencing of the wild species Capsicum chinense. The genome size of the hot pepper was approximately fourfold larger than that of its close relative tomato, and the genome showed an accumulation of Gypsy and Caulimoviridae family elements. Integrative genomic and transcriptomic analyses suggested that change in gene expression and neofunctionalization of capsaicin synthase have shaped capsaicinoid biosynthesis. We found differential molecular patterns of ripening regulators and ethylene synthesis in hot pepper and tomato. The reference genome will serve as a platform for improving the nutritional and medicinal values of Capsicum species.

Fine needle aspiration cytology of parathyroid lesions.

BACKGROUND: There has been an increase in the use of fine needle aspiration cytology (FNAC) for the diagnosis of parathyroid lesions (PLs). Differentiation between a thyroid lesion and a PL is not easy because of their similar features. We reviewed parathyroid aspirates in our institution and aimed to uncover trends in diagnostic criteria. METHODS: We selected 25 parathyroid aspirates (from 6 men and 19 women) confirmed surgically or immunohistochemically from 2006 to 2011. RESULTS: Major architectural findings of PLs include scattered naked nuclei, loose clusters, a papillary pattern with a fibrovascular core, tight clusters, and a follicular pattern. These architectures were commonly admixed with one another. Cytological features included anisokaryosis, stippled chromatin, a well-defined cell border, and oxyphilic cytoplasm. Eighteen of the 25 patients were diagnosed with PL using FNAC. Seven patients had been misdiagnosed with atypical cells (n=2), benign follicular cells (n=2), adenomatous goiter (n=2) and metastatic carcinoma (n=1) in FNAC. Using clinicoradiologic data, the sensitivity of the cytological diagnosis was 86.7%. The cytological sensitivity decreased to 50% without this information. CONCLUSIONS: FNAC of PL is easily confused with thyroid lesions. A combination of cytological parameters and clinical data will be required to improve the diagnostic sensitivity of PLs.

Liquid-based fine needle aspiration biopsy of papillary thyroid carcinoma: logistic regression analysis with conventional and new cytomorphologic features.

OBJECTIVE: The morphological interpretation of liquid-based preparation (LBP) remains a diagnostic challenge due to altered cytomorphology with technical reason. Only a few published accounts of the cytopathological features needed for diagnosis of papillary thyroid carcinoma (PTC) on an LBP exist. We utilized the SurePath LBP system to evaluate conventional and newly recognized cytomorphologic features on histologically confirmed PTC to identify their potent diagnostic significance compared to benign follicular neoplasm (BFN). STUDY DESIGN: One-hundred and three cases of PTC and 84 BFNs were collected using preoperative fine needle aspiration biopsies. We evaluated and compared 16 cytomorphologic findings in PTC and BFN using an LBP. RESULTS: Among the conventional criteria, papillary structures, fewer background colloids and macrophages, hobnail patterns (54.4% in PTC vs. 10.7% in BFN; p < 0.001) and swirling architecture (14.6% in PTC vs. 0% in BFN; p < 0.001; positive predictive value 100.0%) were significant diagnostic findings for PTC compared to BFN. The hobnail pattern was shown as a newly recognized strong diagnostic parameter for PTC (odds ratio 50.157, p < 0.001). CONCLUSION: The identified distinctive cytological criteria may be helpful in cases where conventional criteria for PTC are insufficient. Furthermore, application of these findings, along with classical criteria, may enhance the diagnostic accuracy of PTC by fine needle aspiration biopsy.

Fine-needle aspiration cytology of pleomorphic carcinomas of the lung.

BACKGROUND: Pleomorphic carcinoma (PC) is a rare pulmonary malignancy. Because of its rarity and histological heterogeneity, cytopathologists might suspect PC only rarely on the basis of its cytological specimen. In addition, cytological findings from fine needle aspiration (FNA) specimens have rarely been described. Hence, we investigated the cytological features of FNA in the cases of PC. METHODS: We reviewed 7 FNA specimens of PC. The patients had undergone surgical resection at the Korea Cancer Center Hospital between 2007 and 2011. The cytological features of PC were assessed and compared with the histopathological features of the corresponding surgical specimen. Immunocytochemical analysis with cytokeratin and vimentin was performed on the cell blocks. RESULTS: The tumor cells were either dispersed or arranged in loose aggregates, and generally lacked any glandular or squamous differentiation. Pleomorphic or spindle shape tumor cells were observed, and mono-, bi-, or multi-nucleated giant cells were frequently observed. The background showed necrosis and contained numerous lymphocytes and neutrophils. Immunocytochemically, the tumor cells were positive for cytokeratin and vimentin. CONCLUSIONS: PC displays characteristic cytological features. It might therefore be possible to make an accurate diagnosis of PC by assessing the degree of nuclear atypia.