Arterial Spin-Labeling MR Imaging for the Differential Diagnosis of Venous-Predominant AVMs and Developmental Venous Anomalies.

BACKGROUND AND PURPOSE: Venous-predominant AVMs are almost identical in appearance to developmental venous anomalies on conventional MR imaging. Herein, we compared and analyzed arterial spin-labeling findings in patients with developmental venous anomalies or venous-predominant AVMs, using DSA as the criterion standard. MATERIALS AND METHODS: We retrospectively collected patients with either DVAs or venous-predominant AVMs, each available on both DSA and arterial spin-labeling images. Arterial spin-labeling imaging was visually assessed for the presence of hyperintense signal. CBF measured at the most representative section was normalized to the contralateral gray matter. The temporal phase of developmental venous anomalies or venous-predominant AVMs was measured on DSA as a delay between the first appearance of the intracranial artery and the lesion. Correlation between the normalized CBF and the temporal phase was evaluated. RESULTS: Analysis of 15 lesions (13 patients) resulted in categorization into 3 groups: typical venous-predominant AVMs (temporal phase, <2 seconds), intermediate group (temporal phase between 2.5 and 5 seconds), and classic developmental venous anomalies (temporal phase, >10 seconds). Arterial spin-labeling signal was markedly increased in the typical venous-predominant AVM group, while there was no discernible signal in the classic developmental venous anomaly group. In the intermediate group, however, 3 of 6 lesions showed mildly increased arterial spin-labeling signal. The normalized CBF on arterial spin-labeling and the temporal phase on DSA were moderately negatively correlated: r(13) = 0.66, P = .008. CONCLUSIONS: Arterial spin-labeling may predict the presence and amount of arteriovenous shunting in venous-predominant AVMs, and using arterial spin-labeling enables confirmation of typical venous-predominant AVMs without DSA. However, lesions with an intermediate amount of shunting suggest a spectrum of vascular malformations ranging from purely vein-draining developmental venous anomalies to venous-predominant AVMs with overt arteriovenous shunting.

High-Intensity Physical Activity with High Serum Vitamin D Levels is Associated with a Low Prevalence of Osteopenia and Osteoporosis: A Population-Based Study.

We found that combination of high-intensity PA and high 25(OH)D levels was associated with low prevalence of osteoporosis/osteopenia. In addition, the prevalence of osteoporosis was lower in the low PA with high 25(OH)D levels than in the moderate or high PA with low 25(OH)D levels. INTRODUCTION: The aim of this study was to explore the association of physical activity (PA) and serum 25-hydroxyvitamin D (25[OH]D) levels with osteopenia/osteoporosis. METHODS: The Korean National Health and Nutrition Examination Survey data from 2008 to 2011 were used in this study. Data from 6868 individuals were selected. Each individual's level of PA was classified as 'low', 'moderate', or 'high'. Serum 25(OH)D levels were classified as 'low' or 'high'. Accordingly, the combined PA and 25(OH)D groups were divided into 6 groups. Bone mineral density (BMD) was classified as 'normal (T score ≥ - 1.0)', 'osteopenia (- 2.5 < T score < - 1.0)' or 'osteoporosis (T score ≤ - 2.5)'. Crude and adjusted odds ratios (AORs) with 95% confidence intervals (CIs) were calculated using multinomial logistic regression models. RESULTS: The AORs (95% CIs) for osteopenia were 0.64 (0.50-0.83) in the high PA with high 25(OH)D group and 0.69 (0.53-0.88) in the moderate PA with high 25(OH)D group. The AORs (95% CIs) for osteoporosis were increased in the groups in ascending order as follows: high PA with high 25(OH)D (0.40 [0.28-0.57]) < moderate PA with high 25(OH)D (0.47 [0.33-0.66]) < low PA with high 25(OH)D (0.59 [0.42-0.83]) < high PA with low 25(OH)D (0.70 [0.49-1.00]) < moderate PA with low 25(OH)D (0.76 [0.53-1.07]) < low PA with low 25(OH)D. This result was consistent in males but not evident in females. CONCLUSION: We suggest that the combination of high-intensity PA and high 25(OH)D levels is positively associated with high BMD.

Suspected Metallic Embolization Distal to Coiled Intracranial Aneurysms Detectable by Susceptibility-Weighted MR Imaging.

BACKGROUND AND PURPOSE: After endovascular coiling of intracranial aneurysms, round dark parenchymal lesions believed to be particulate metal are sometimes encountered in MR imaging studies of the brain. We used SWI to assess the frequency of such occurrences, in addition to exploring likely causes and clinical implications. MATERIALS AND METHODS: We reviewed 700 MR imaging studies performed between September 2018 and March 2019 at our institution as follow-up monitoring of coiled intracranial aneurysms. Any sizeable (>5 mm) rounded dark-signal lesions encountered were presumed to be metallic. The magnitudes and locations of such lesions were recorded. In patients with these lesions, pertinent procedural documentation was screened for devices used, including coils, microcatheters, microguidewires, and stents. Medical records were also examined to determine whether any related symptoms ensued. RESULTS: Twenty patients (2.8%) exhibited a total of 25 lesions on SWI. Diameters ranged from 5 to 11 mm (median, 8 mm). All except 2 lesions were located in brain regions downstream from aneurysms, but all lesions occupied vascular territories of vessels used to place guiding catheters. Other than the Synchro 14, which was routinely deployed, no device was regularly used in patients with SWI-detectable lesions; and none of the affected patients developed focal neurologic symptoms as a consequence. CONCLUSIONS: Although the origins remain unclear, distal embolization of particulate metal distal to coiled cerebral aneurysms is occasionally observed on follow-up MR imaging studies. Such lesions, however, seem to have no apparent clinical impact.

Contralateral Approach to Coil Embolization of Proximal A1 Aneurysms Using the Anterior Communicating Artery.

BACKGROUND AND PURPOSE: Aneurysms arising from the proximal A1 segment of the anterior cerebral artery are rare, and their distinctive configurations often pose technical challenges during endovascular embolization. Herein, we present 11 patients with proximal A1 aneurysms requiring a contralateral approach (via the anterior communicating artery) to coil embolization. MATERIALS AND METHODS: From a prospectively collected data repository, we retrieved records of 11 patients consecutively treated for proximal A1 aneurysms between January 2011 and March 2018. In each instance, coil embolization was performed by the contralateral route. Outcomes were analyzed in terms of morphologic features and clinical status. RESULTS: Aneurysms in all 11 patients were directed posteriorly and were small (<5 mm). A contralateral approach (via the anterior communicating artery) was used after ipsilateral attempts at aneurysm selection failed in each instance, despite using a variety of microcatheters. Single punctures and single guiding catheters sufficed in 9 patients, but 2 patients required dual punctures and 2 guiding catheters. All endovascular treatments ultimately yielded excellent outcomes. Although 1 symptomatic infarct was manifested in the course of ipsilateral treatment, no morbidity or mortality resulted from the contralateral access. CONCLUSIONS: Due to angio-anatomic constraints, a contralateral strategy for coil embolization of proximal A1 aneurysms is acceptable if ipsilateral access is technically prohibitive and the vessels (contralateral A1 and anterior communicating artery) are amenable to the passage of microdevices.

Comparison of Clinical Outcomes of Intracranial Aneurysms: Procedural Rupture versus Spontaneous Rupture.

BACKGROUND AND PURPOSE: Procedural rupture of an intracranial aneurysm is a devastating complication in endovascular treatment. The purpose of this study was to evaluate the clinical outcomes of patients with procedural rupture of unruptured saccular intracranial aneurysms compared with those with spontaneously ruptured aneurysms. MATERIALS AND METHODS: A retrospective review was performed for 1340 patients with 1595 unruptured saccular intracranial aneurysms that underwent endovascular coil embolization between February 2010 and December 2014. The clinical outcomes of patients with procedural rupture of unruptured saccular intracranial aneurysms were compared with those of 198 patients presenting with spontaneously ruptured aneurysms. RESULTS: In this series, procedural rupture developed in 19 patients (1.4% per patient and 1.2% per aneurysm), and the morbidity related to procedural rupture was 26.3% (95% confidence interval, 8.5%-61.4%) with no mortality. Hunt and Hess scale grades and hospitalization days of patients with procedural rupture were equivalent to those of patients presenting with spontaneous aneurysm rupture. Subsequent treatment procedures after hemorrhage (including lumbar drainage, extraventricular drainage, decompressive craniectomy, and permanent shunt) showed no difference between the 2 groups. The hemorrhage volumes were smaller in the procedural-rupture group (P = .03), and the endovascular vasospasm therapies tended to be more frequently required in the spontaneous aneurysm-rupture group (P = .08). At postictus 6 months, the proportion of modified Rankin Scale scores of ≥2 were lower in the procedural-rupture group (5.3% versus 26.8%, P = .049). In multivariate analysis, spontaneous aneurysm rupture was a significant risk factor for worse clinical outcome (OR = 14.9; 95% CI, 1.2-193.1; P = .039). CONCLUSIONS: This study showed better clinical outcomes in the procedural-rupture group. Even though there is a potential chance of aneurysm rupture during treatment, the clinical outcomes after procedural bleeds seem to be more favorable than those of spontaneous rupture.

Risk Factor Analysis of Recanalization Timing in Coiled Aneurysms: Early versus Late Recanalization.

BACKGROUND AND PURPOSE: Long-term documentation of anatomic and angiographic characteristics pertaining to the timing of recanalization in coiled aneurysms has been insufficient. Our intent was to analyze and compare early and late-phase recanalization after coiling, identifying respective risk factors. MATERIALS AND METHODS: A total of 870 coiled saccular aneurysms were monitored for extended periods (mean, 30.8 ± 8.3 months). Medical records and radiologic data were also reviewed, stratifying patients as either early (n = 128) or late (n = 52) recanalization or as complete occlusion (n = 690). Early recanalization was equated with confirmed recanalization within 6 months after the procedure, whereas late recanalization was defined as verifiable recanalization after imaging confirmation of complete occlusion at 6 months. A multinomial regression model served to assess potential risk factors, the reference point being early recanalization. RESULTS: Posterior circulation (P = .009), subarachnoid hemorrhage at presentation (P = .011), second attempt for recanalized aneurysm (P < .001), and aneurysm size >7 mm (P < .001) emerged as variables significantly linked with early recanalization (versus complete occlusion). Late (versus early) recanalization corresponded with aneurysms ≤7 mm (P = .013), and in a separate subanalysis of lesions ≤7 mm, aneurysms 4-7 mm showed a significant predilection for late recanalization (P = .008). However, the propensity for complete occlusion in smaller lesions (≤7 mm) increased as the size diminished. CONCLUSIONS: Although long-term complete occlusion after coiling was more likely in aneurysms ≤7 mm, such lesions were more prone to late (versus early) recanalization, particularly those of 4-7 mm in size. Long-term follow-up imaging is thus appropriate in aneurysms >4 mm to detect late recanalization of those formerly demonstrating complete occlusion.

A Case of Ectopic Paragonimiasis in a 17th Century Korean Mummy.

Archaeoparasitological studies on fossilized feces obtained from Joseon Dynasty (1392-1910 CE) mummies have provided invaluable data on the patterns of parasitic infection in pre-modern Korean societies. In our recent radiological investigation of a 17th century Joseon mummy discovered in Cheongdo (South Korea), we located a liver mass just below the diaphragm. Anatomical dissection confirmed the presence of a mass of unknown etiology. A subsequent parasitological examination of a sample of the mass revealed a large number of ancient Paragonimus sp. eggs, making the current report the first archaeoparasitological case of liver abscess caused by ectopic paragonimiasis.

Do Contrast-Fill Patterns Immediately After Coil Embolization of Small Saccular Aneurysms Impact Long-Term Results?

PURPOSE: It is generally accepted that filling of a saccular aneurysm with contrast immediately after coil embolization predisposes to later recanalization. However, not all such scenarios evolve similarly over time. We investigated outcomes of small (≤ 7 mm) aneurysms with contrast-filled sacs immediately after coil embolization, evaluating the impact of pattern and degree of filling on subsequent recanalization. METHODS: Between January, 2008 and December, 2010, 186 small (≤ 7 mm) saccular aneurysms that retained contrast after coil embolization accrued for this study. Lesions were categorized by pattern (eccentric vs. concentric) and degree of filling on working projections. Clinical and morphologic factors were also analyzed to assess impact on subsequent recanalization. Morphologic outcomes at 6 months or more were assessed. RESULTS: In 93.5 % (174/186) of aneurysms with visible contrast retention, complete occlusion was evident on follow-up imaging studies at 6 months. Multiple logistic regression analysis indicated that eccentric (vs. concentric) contrast filling carried greater risk of subsequent recanalization (p = 0.020). Stent placement and progressive occlusion were also linked, falling short of statistical significance (p = 0.089). Of 166 progressively occluded aneurysms followed for more than 12 months (mean, 30.8 ± 7.3 months), 158 (95.2 %) exhibited stable occlusion. CONCLUSION: Small (≤ 7 mm) aneurysms that retain contrast immediately after coil embolization are more likely to become completely occluded over time through progressive thrombosis. However, an eccentric fill pattern may predispose to recanalization.

Acute carbon monoxide poisoning: MR imaging findings with clinical correlation.

PURPOSE: To assess the magnetic resonance imaging (MRI) findings, including diffusion-weighted imaging (DWI) in patients with acute carbon monoxide (CO) poisoning and correlate MRI findings with carboxyhemoglobin levels. MATERIALS AND METHODS: The MRI examinations and medical records of seven men with a mean age of 43±16.0years (SD) (range: 25-63 years) with acute CO poisoning were reviewed. MRI examinations were analyzed with respect to lesion location, imaging presentation on T1- and T2-weighted images, and diffusion characteristics on DWI and apparent diffusion coefficient (ADC) maps. We also evaluated clinical features and laboratory findings including the presenting symptoms and signs, carboxyhemoglobin level, and treatment. RESULTS: All seven patients presented with mental status change. The level of carboxyhemoglobin ranged between 8.3% and 34.8% (normal<1.5%). All seven patients (7/7, 100%) showed restricted diffusion of the lesions on ADC maps and bilateral involvement of globus pallidus. The mean ratios of ADC values was 0.63±0.15 (SD) (range: 0.46-0.92) on bilateral globi pallidi. Cerebral cortex, cerebral white matter, cerebellum, hippocampus, amygdala, splenium of corpus callosum, midbrain and insula were also involved. CONCLUSION: Bilateral globi pallidi with restricted diffusion may be a characteristic MRI feature in patients with acute CO poisoning. However, the relationship was not certain between the carboxyhemoglobin levels and the variety or severity of MRI findings.

Fate of Coiled Aneurysms with Minor Recanalization at 6 Months: Rate of Progression to Further Recanalization and Related Risk Factors.

BACKGROUND AND PURPOSE: Minor recanalization in coiled aneurysms may remain stable with time or may progress to major recanalization. Our aim was to monitor the aneurysms displaying minor recanalization in imaging studies at 6 months, gauging major recanalization rates and related risk factors through extended follow-up. MATERIALS AND METHODS: Sixty-five aneurysms (in 65 patients) showing minor recanalization in follow-up imaging at 6 months were reviewed retrospectively. Medical records and radiologic data accruing during extended monitoring (mean, 24.8 ± 8.2 months) were assessed. Univariate and multivariate analyses were conducted to identify risk factors for progression from minor-to-major recanalization. RESULTS: Progression to major recanalization was observed in 24 (36.9%) of the initially qualifying aneurysms during a follow-up of 112.5 aneurysm-years, for an annual rate of 17.84% per aneurysm-year. Progression was determined chronologically as follows: 14 (58.3%) at 6 months, 8 (33.3%) at 18 months, and 2 (8.4%) at 30 months. Stent deployment significantly decreased the occurrence of major recanalization (OR = 0.22, P = .03), whereas antiplatelet therapy (OR = 0.82, P = .75), posterior location (OR = 0.24, P = .20), and second coiling for recanalized aneurysms (OR = 0.96, P = .96) were unrelated. CONCLUSIONS: Our analysis determined a 36.9% rate of major recanalization during a follow-up of 112.5 aneurysm-years in coiled aneurysms showing minor recanalization at 6 months. Stent deployment alone conferred a protective effect, preventing further recanalization without additional treatment. Given the fair probability of late major recanalization, aneurysms showing minor recanalization at 6 months should be monitored diligently, particularly in the absence of stent placement.

Effect of low speed drilling on osseointegration using simplified drilling procedures.

Our aim was to find out whether simplified drilling protocols would provide biological responses comparable to those of conventional drilling protocols at the low rotational speed of 400rpm. Seventy-eight root form endosseous implants with diameters of 3.75, 4.2, and 5mm were placed into canine tibias and allowed to heal for 3 and 5 weeks. After the dogs had been killed, the samples of implanted bone were retrieved and processed for non-decalcified histological sectioning. Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) analyses were made on the histological sections. Implants treated by the simplified protocol resulted in BIC and BAFO values comparable to those obtained with the conventional drilling protocol, and there were no significant differences in the technique or diameter of the drilling. The results suggest that the simplified procedure gives biological outcomes comparable to those of the conventional procedure.

Hemorrhagic Transformation of Scrub Typhus Encephalitis: A Rare Entity.

Central nervous system (CNS) involvement of scrub typhus infection is well known. Most CNS involvement of scrub typhus infection present as meningitis or encephalitis. We report on a patient suffering from hemorrhagic transformation of intracranial lesions caused by Orientia tsutsugamushi. A 53-year-old female farmer who was infected by scrub typhus was treated with doxycycline and recovered from the systemic illness. However, headache persisted. Brain radiologic studies revealed acute intracranial hemorrhage and enhancing lesion, which implied a CNS involvement. Hemorrhagic transformation of encephalitis by scrub typhus is very rare complication and to our best knowledge, this is the first report of hemorrhagic transformation of scrub typhus encephalitis. Clinician should consider the possibility of hemorrhagic transformation of encephalitis in cases of scrub typhus infection.

A prospective randomised comparison of two insertion methods for i-gel placement in anaesthetised paralysed patients: standard vs. rotational technique.

In this prospective randomised study, we compared two techniques for i-gel(™) insertion. One hundred and eighty-one anaesthetised, paralysed adult patients were randomly allocated into one of two groups. In the standard group (n = 91), the i-gel was inserted using the standard technique. In the rotation group (n = 90), the i-gel was rotated 90° anticlockwise in the mouth and re-rotated in the hypopharynx to the original alignment. The success rate, insertion time, air leak pressure and complications were assessed. The success rate for insertion at the first attempt was lower for the standard technique, 78 (86%) vs. 87 (97%; p = 0.016). The mean (SD) insertion time was longer (26.9 (14.5) s vs. 22.4 (10.2) s; p = 0.016) and air leak pressure was lower (22.5 (10.4) cm H2O vs. 27.1 (9.4) cm H2O; p = 0.002) in the standard group. The incidence of bloodstaining was higher with the standard technique (8 (9%) vs. 1 (1%); p = 0.034). This study suggests that the rotational technique is superior to the standard technique for i-gel insertion.

Effect of tamsulosin on stone expulsion in proximal ureteral calculi: an open-label randomized controlled trial.

AIM: Medical expulsive therapy (MET) using alpha-blockers is effective for distal ureteral calculi (UC). We aimed to evaluate the efficacy of tamsulosin for proximal UC expulsion. MATERIALS AND METHODS: An open-label randomized controlled trial was conducted with 108 patients who agreed to conservative management for single, radiopaque, proximal UC ≤ 6 mm and were randomized into group A (n = 54, conservative managements only) or B (n = 54, 0.2 mg tamsulosin once a day). The primary end-point was stone passage rates (SPR) in the intention-to-treat population in 4 treatment weeks. The secondary end-points were estimated in per-protocol population and were time to stone passage, post-trial Euro-quality-of-life (EuroQOL) score, oral analgesic requirements, and willingness to undergo conservative treatment again. RESULTS: The two groups were well balanced in terms of baseline patient and stone characteristics. Seventy nine patients (73.2%; 35 of group A and 44 of group B) completed the study protocol. The overall SPR was 60.2% (65/108). Group B had a higher SPR (74.1%; 40/54) than group A (46.3%; 25/54; p = 0.003) and a significantly shorter time to stone passage (mean days, A: 19.6 vs. B: 14.3, p = 0.005). The groups did not differ in post-trial EuroQOL score or oral analgesic requirements, whereas 74.3% (26/35) of group A and 90.9% (40/44) of group B were willing to undergo conservative treatment again (p = 0.048). Univariate logistic regression analysis showed that stone size (OR = 1.447, p = 0.045) and tamsulosin treatment (OR = 3.314, p = 0.004) significantly predicted stone expulsion. On multivariate analysis, only tamsulosin was statistically significant (OR=3.198, p = 0.021). CONCLUSIONS: Tamsulosin was associated with significantly higher stone expulsion rate and shorter expulsion time in proximal UC ≤ 6 mm compared with conservative managements only. Our results indicate that similar to patients with distal UC, MET using tamsulosin is a reasonable treatment option for patients with proximal UC.

Interleukin-18 as an efficient marker for remission and follow-up in patients with inactive adult-onset Still's disease.

OBJECTIVES: Diagnosis of adult-onset Still's disease (AOSD) is difficult because of a lack of pathognomonic findings and markers. The aim of this study was to investigate the efficacy of interleukin (IL)-18 and free IL-18 in the diagnosis and follow-up of patients with AOSD. METHOD: Levels of inflammatory cytokines, IL-18, IL-18 binding protein (IL-18BP), and free IL-18 were compared in 80 AOSD patients and 90 controls. The AOSD patients were divided into active and inactive groups according to disease activity, and the inactive patients were subdivided into a remission subgroup and a low disease activity subgroup. We compared erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), ferritin, IL-18, and free IL-18 as disease activity markers in the AOSD patients. Serial serum levels of activity markers were measured in 52 of the 80 AOSD patients at 3- to 6-month intervals. RESULTS: There were significantly higher levels of IL-18 and free IL-18 in the AOSD patients than in the controls. IL-18 and free IL-18 were significantly higher in the active group than the inactive group (p < 0.001 for all). Unlike other activity markers, IL-18 and free IL-18 levels in the low disease activity subgroup were significantly higher than those in the remission subgroup within the inactive group (p = 0.004 and 0.005, respectively). During serial follow-up, ferritin and IL-18 showed a significant decrease in the responder and remission subgroup. CONCLUSIONS: IL-18 might be an efficient marker for diagnosis and follow-up of AOSD and might also be a useful predictor of remission, especially in clinically inactive patients.

Evaluation of FOXP3 expression in canine mammary gland tumours.

The expression of the transcription factor forkhead box P3 (FOXP3) was examined in 62 canine mammary gland tumours via immunohistochemical analysis and association with the known expression of the oestrogen receptor-alpha (ERα), progesterone receptor (PR), c-erbB-2 receptor (HER2/neu), and survival. Positive staining for FOXP3 was present in 22.6% of the tumours and was associated with the histological type. Negative staining for FOXP3 was associated with positive ERα and PR expression (P < 0.001). The expression of FOXP3 in canine mammary gland tumours was significantly associated with the disease-free survival time (P = 0.029). The FOXP3 expression was not an independent prognostic factor in the multivariate analysis, though. The negative expression of FOXP3 in the canine mammary gland tumours was found to be related to histopathologic benignity and a longer survival time in canine mammary gland tumours.

Evaluation of bone response to various anorganic bovine bone xenografts: an experimental calvaria defect study.

This in vivo study investigated the in vivo performance of two newly developed synthetic bone substitutes and compared them to commercially available xenografts (Bio-Oss, Geistlich Pharma AG, Switzerland; OsteoGraf, Dentsply, USA). The materials were tested in a rabbit calvaria model, and the bone forming properties were observed at 4 and 8 weeks after implantation by means of histomorphometry and micro computed tomography (micro-CT). Defects without any graft material were used as negative controls. Micro-CT showed that all materials tested presented new bone formation that filled the defects at both time points, whereas the negative control presented less bone formation, with soft tissue infiltration into the defects. Comparable bone fill percentages were observed for histomorphometric and micro-CT results. Even though no statistically significant difference was found quantitatively between all of the bone graft substitute groups, a higher mean decrease in graft material filling the defects, along with higher remodelling activity, was evident for the experimental materials compared to the commercially available xenografts at 8 weeks. The results indicate that the experimental materials possess high degradability, along with osteoconduction comparable to commercially available xenografts.

Characteristics of primary cutaneous lymphoma according to WHO-EORTC classification in Korea.

BACKGROUND: Primary cutaneous lymphoma (PCL) is an extranodal non-Hodgkin lymphoma with primary involvement of the skin. Epidemiological data on PCLs according to the World Health Organization/European Organization for Research and Treatment of Cancer classification (WHO-EORTC) has not been investigated in Korea to date. AIM: To evaluate the demographic characteristics, clinical and histological features, and survival data of patients with PCL according to the WHO-EORTC classification. METHODS: In total, 93 patients with PCL were retrospectively identified from an extensive review of medical records over a 16-year period. RESULTS: The tumours found included primary cutaneous CD30+ lymphoproliferative disorders, extranodal natural killer/T-cell lymphoma and primary cutaneous diffuse large B-cell lymphoma. We found that 81.6% of the patients had primary cutaneous T-cell and natural killer-cell lymphoma, and 16.2% had primary cutaneous B-cell lymphoma, with 2.2% having precursor haematological neoplasms. The median age was 52 years (range 3-95) and the male : female ratio was 1: 1.16. The 5-year survival rate was 92.5%. CONCLUSIONS: The incidence rates of many PCL subtypes in Koreans differ from those of other countries.