Comparison of time courses in postoperative functional outcomes between simultaneous bilateral and unilateral total knee arthroplasty with propensity score matching.

INTRODUCTION/OBJECTIVES: No consensus has been reached on which is better in terms of functional outcomes between simultaneous bilateral and unilateral total knee arthroplasty (TKA). As patient characteristics, such as age, sex, and body mass index, have significant effects on functional outcomes after TKA, these factors should be matched before comparisons are made. This study aimed to compare time courses in functional outcomes between simultaneous bilateral TKA and unilateral TKA after matching the patient characteristics. MATERIALS AND METHODS: In this retrospective study, the clinical records of patients admitted to a hospital were reviewed. Of 425 patients, 43 underwent simultaneous bilateral TKA, whereas 382 underwent unilateral TKA. Propensity score matching was performed for age, sex, and body mass index between simultaneous bilateral and unilateral TKA patients. Therapists measured pain intensity, knee extensor strength, and knee-specific functional outcomes by using the new knee society score, including total score, symptoms, patient satisfaction, patient expectations, and functional activities preoperatively and 3 and 12 months postoperatively. Two-way repeated analysis of variance was performed to compare the time courses in functional outcomes between simultaneous bilateral and unilateral TKA. RESULTS: After propensity score matching, 40 patients each for underwent bilateral TKA and unilateral TKA were selected. Knee extensor strength in simultaneous bilateral TKA patients was significantly lower than that in unilateral TKA patients at 3 months postoperatively (p = 0.04). A significant interaction was observed between the effects of time and group on knee extensor strength (F [1, 78] = 3.338; interaction: p = 0.042; η2 = 0.052). No significant interactions were found among the other variables measured. CONCLUSIONS: Patients who underwent simultaneous bilateral TKA should undergo postoperative rehabilitation focused on alleviating delayed recovery in knee extensor strength during the acute phase.

Contralateral knee pain exacerbation after total knee arthroplasty and its impact on functional activity.

INTRODUCTION: The purposes of the present study were to (1) describe the prevalence of contralateral knee pain exacerbation after total knee arthroplasty (TKA), (2) explore the risk factors for pain exacerbation, and (3) verify the association of contralateral knee pain with future functional activity. MATERIALS AND METHOD: We consecutively recruited outpatients with osteoarthritis of both knees who had primary TKA planned. The contralateral knee pain using a Numerical Rating Scale (NRS) and the functional activities subdomain of the new Knee Society Knee Scoring System (KSS) were assessed preoperatively and at 1, 3, and 6 months postoperatively. Among patients with < 5 NRS points preoperatively, we described the frequency of the contralateral knee pain exacerbation, defined as a ≥ 2-point increase from preoperative pain at each postoperative visit. An exploratory analysis was performed to identify preoperative risk factors for contralateral knee pain exacerbation. A linear mixed model was fit to examine the association of the contralateral knee pain with KSS functional activities at subsequent visits. RESULTS: Among 315 patients, 14.6%, 24.1%, and 27.6% of patients experienced contralateral knee pain exacerbation at 1, 3, and 6 months postoperatively, respectively. The identified preoperative risk factors were low quadriceps strength and higher Kellgren-Lawrence grade on the non-operative knee, along with severe pain on the operative knee. The magnitude of the association between contralateral knee pain and worsening KSS functional activities increased with subsequent visits (p for interaction < 0.001). CONCLUSION: The frequency and impact of pain exacerbation on the contralateral knee increase after TKA and should be carefully evaluated for a prolonged period of time.

Comparison of Acute-Phase Pain Intensity, Pain Trajectory, and the Number of Analgesics Administered between Total and Unicompartmental Knee Arthroplasties.

We aimed to compare the variables of pain intensity, pain trajectory, and the number of analgesics administered during the acute phase between total and unicompartmental knee arthroplasties. This prospective cohort study recruited 445 patients who planned to undergo knee arthroplasty. Pain intensity was evaluated during hospitalization, and 1 month postoperatively using a numerical rating scale. Pain trajectory (slope and intercept) was calculated using pain intensity data from postoperative days 1 to 4. The number of analgesics administered for worsening pain was monitored during hospitalization. Multiple linear regression analysis with adjustment for potential confounders was conducted to investigate the impact of surgery type on pain variables. Data for 208 and 189 patients who had undergone total and unicompartmental knee arthroplasties, respectively, were included in this study. Pain intensity and pain trajectory were similar between the two surgeries. The number of analgesics administered on postoperative day 3 (p = 0.01) and day 4 (p = 0.03), as well as total number (p = 0.01), were lower for unicompartmental knee arthroplasty than for total knee arthroplasty. Multiple linear regression analysis showed that the type of surgery affected the total number of analgesics administered (ß = - 1.24, p < 0.01, 95% confidence interval: -1.80 to -0.62). This study suggests that pain characteristics observed during the acute phase differ between total and unicompartmental knee arthroplasties. Postoperative pain should be managed, and rehabilitation should be provided at similar levels after the second postoperative day in total and unicompartmental knee arthroplasty patients.

Possible Neoangiogenesis in Achilles Tendon Xanthoma with Familial Hypercholesterolemia: A Novel Approach to Achilles Tendon Xanthoma.

Achilles tendon xanthoma (ATX) is one of the typical features of familial hypercholesterolemia (FH). The morphological evaluation of ATX by X-ray radiography is widely recognized; however, the utility of other imaging modalities remains unclear. We herein report two cases of FH in which Doppler ultrasound imaging demonstrated a microvascular flow in ATX that only rarely could be observed in normal Achilles tendons. Neoangiogenesis accompanies chronic inflammation and it may play an important role in the deposition of cholesterol crystals leading to ATX. In addition to the morphological evaluation of ATX, the assessment of neoangiogenesis may therefore be essential for the evaluation of ATX.

Automated system for diagnosing endometrial cancer by adopting deep-learning technology in hysteroscopy.

Endometrial cancer is a ubiquitous gynecological disease with increasing global incidence. Therefore, despite the lack of an established screening technique to date, early diagnosis of endometrial cancer assumes critical importance. This paper presents an artificial-intelligence-based system to detect the regions affected by endometrial cancer automatically from hysteroscopic images. In this study, 177 patients (60 with normal endometrium, 21 with uterine myoma, 60 with endometrial polyp, 15 with atypical endometrial hyperplasia, and 21 with endometrial cancer) with a history of hysteroscopy were recruited. Machine-learning techniques based on three popular deep neural network models were employed, and a continuity-analysis method was developed to enhance the accuracy of cancer diagnosis. Finally, we investigated if the accuracy could be improved by combining all the trained models. The results reveal that the diagnosis accuracy was approximately 80% (78.91-80.93%) when using the standard method, and it increased to 89% (83.94-89.13%) and exceeded 90% (i.e., 90.29%) when employing the proposed continuity analysis and combining the three neural networks, respectively. The corresponding sensitivity and specificity equaled 91.66% and 89.36%, respectively. These findings demonstrate the proposed method to be sufficient to facilitate timely diagnosis of endometrial cancer in the near future.

U-TEST, a simple decision support tool for the diagnosis of sarcopenia in orthopaedic patients: the Screening for People Suffering Sarcopenia in Orthopedic cohort of Kobe study (SPSS-OK).

We aimed to develop and validate a new simple decision support tool (U-TEST) for diagnosis of sarcopenia in orthopaedic patients. We created seventeen candidate original questions to detect sarcopenia in orthopaedic patients with sarcopenia through expert opinions and a semi-structured interview. To derive a decision support tool, a logistic regression model with backward elimination was applied to select variables from the seventeen questions, age and underweight (BMI < 18·5 kg/m2). Sarcopenia was defined by Asian Working Group for Sarcopenia 2019 criteria. After assigning a score to each selected variable, the sum of scores was calculated. We evaluated the diagnostic performance of the new tool using a logistic regression model. A bootstrap technique was used for internal validation. Among a total of 1334 orthopaedic patients, sixty-five (4·9 %) patients were diagnosed with sarcopenia. We succeeded in developing a 'U-TEST' with scores ranging from 0 to 11 consisting of values for BMI (Underweight), age (Elderly) and two original questions ('I can't stand up from a chair without supporting myself with my arms' (Strength) and 'I feel that my arms and legs are thinner than they were in the past' (Thin)). The AUC was 0·77 (95 % CI 0·71, 0·83). With the optimal cut-off set at 3 or greater based on Youden's index, the sensitivity and the specificity were 76·1 and 63·6 %, respectively. In orthopaedic patients, our U-TEST scoring with two questions and two simple clinical variables can help to screen for sarcopenia.

Disentangling Associations Between Serum Muscle Biomarkers and Sarcopenia in the Presence of Pain and Inflammation Among Patients With Osteoarthritis: The SPSS-OK Study.

BACKGROUND/OBJECTIVE: Reduction of muscle markers, such as creatine phosphokinase (CK), in rheumatic diseases and its association with reduced muscle mass may be of clinical importance in osteoarthritis (OA). Considering the complexity of secondary sarcopenia, clarifying the association between muscle markers and sarcopenia and disentangling the involvement of OA-related conditions are of clinical importance. We investigated the association between serum muscle biomarkers and sarcopenia among patients with OA, considering the presence of pain and inflammation. METHODS: Overall, 1425 patients with knee and hip OA scheduled for joint replacement surgery were included in a single-center cross-sectional study from Screening for People Suffering Sarcopenia in Orthopedic cohort of Kobe study. Primary outcome was sarcopenia defined by 2 criteria (the Asian Working Group for Sarcopenia and the European Working Group on Sarcopenia in Older People). Pain and inflammation were measured using the numeric rating scale and serum C-reactive protein (CRP) levels, respectively. Associations between the biomarkers (serum CK, aspartate aminotransferase, alanine aminotransferase) and sarcopenia were examined using logistic regression models. RESULTS: Sarcopenia by the Asian Working Group for Sarcopenia criteria was present in 4.0% of patients. In adjusted analyses, sarcopenia was negatively associated with higher serum CK levels, but not with serum aspartate aminotransferase or alanine aminotransferase levels independent of pain score and serum CRP. Neither pain score nor serum CRP level was associated with sarcopenia. Similar results were found when the European Working Group on Sarcopenia in Older People criteria were used. CONCLUSIONS: Serum CK was associated with sarcopenia, suggesting the potential usefulness for sarcopenia detection regardless of pain or inflammation in OA.

Usefulness of biopsy by office hysteroscopy for endometrial cancer: A case report.

A diagnostic biopsy for endometrial cancer is performed via dilation and curettage (D&C). However, D&C may miss endometrial cancer lesions due to of its 'blind' approach. Hysteroscopy is a useful method that can be used to detect endometrial cancer lesions. In addition, office hysteroscopy is easy to be scheduled and does not require anesthesia. The patient was a 40-year-old woman with suspected endometrial cancer; however, it could not be diagnosed by D&C and biopsy using hysteroscopy during hospitalization. Office hysteroscopy during the proliferative phase indicated that the suspicious endometrial cancerous lesion was minimal at the isthmus of the uterus with atypical vessels and a white spot, for which biopsy was performed. Pathological diagnosis was endometrioid carcinoma with squamous differentiation, G1. Therefore, total laparoscopic hysterectomy, bilateral salpingo-oophorectomy and pelvic lymphadenectomy were performed. In this case, it was difficult to detect minimal lesion in the secretory phase because the endometrial thickness hid the endometrial cancer. It is easy to perform office hysteroscopy in the proliferative phase. This case indicated that office hysteroscopy is a useful method to diagnose and perform biopsy for minimal lesions.

Effect of improvement in quadriceps strength asymmetry on trunk movement asymmetry after total knee arthroplasty.

BACKGROUND: Patients with knee osteoarthritis (OA) demonstrate trunk movement asymmetry during walking; this asymmetry is associated with disability and quadriceps strength asymmetry. RESEARCH QUESTION: What are the differences between trunk movement asymmetries before and after total knee arthroplasty (TKA) and associations between the changes in trunk movement asymmetry and quadriceps strength asymmetry? METHODS: In this prospective cohort study, 27 patients (mean age, 71.0 years; women, 85.2%) were assessed at 1 month before and 6 months after surgery. Trunk movement asymmetry (harmonic ratio) was assessed at their preferred pace using a triaxial accelerometer. The isometric quadriceps strength was evaluated using a hand-held dynamometer, and the quadriceps strength inter-limb absolute difference was calculated. Multivariate analyses were performed to compare the trunk movement asymmetries before and after surgery with covariate adjustment (gait pain, gait velocity, and non-operated-limb Kellgren and Lawrence [K&L] grade) and to investigate the association between the changes in trunk movement asymmetry and quadriceps strength inter-limb difference with covariate adjustment (age, sex, and non-operated-limb K&L grade). RESULTS: The trunk movement asymmetry in the medio-lateral (mean difference, 0.61; 95% confidence interval [CI], 0.22 to 1.00) and antero-posterior (mean difference, 1.15; 95% CI, 0.48 to 1.83) directions significantly decreased postoperatively compared with the preoperative results. A decreased quadriceps strength inter-limb difference was significantly associated with a decreased medio-lateral trunk movement asymmetry (ß = 0.68; 95% CI, 0.30 to 1.06). SIGNIFICANCE: TKA plays an important role in the improvement of trunk stability during walking in patients with knee OA. Decreasing quadriceps strength asymmetry may be a key to improving trunk movement asymmetry.

Gait Variability in Women With Hip Osteoarthritis Before and After Total Hip Replacement: A Prospective Cohort Study.

OBJECTIVE: Gait variability changes before and after total hip arthroplasty are unclear. This study aimed to investigate gait variability changes in hip osteoarthritis patients before and after total hip arthroplasty and to examine the relationships between gait variability changes and hip function. DESIGN: Twenty-three female patients with hip osteoarthritis (61.0 ± 7.1 yrs) and 10 healthy female participants (57.8 ± 3.9 yrs) were assessed 1 mo before and 12 mos after surgery. Heel and lower trunk accelerations were measured using two triaxial accelerometers. The coefficient of variation of stride time for gait variability of lower limb motions and the harmonic ratio for trunk variability were calculated. Radiographic leg-length discrepancy, hip abductor strength, hip abduction, extension range of motion, and pain level during gait were measured. RESULTS: The coefficient of variation was significantly decreased after total hip arthroplasty and was comparable with that in healthy individuals. Although postoperative harmonic ratios were greater than preoperative harmonic ratios, they were not comparable with those in healthy individuals. The coefficient of variation changes were associated with pain relief during gait. Harmonic ratio changes were associated with hip abductor strength, extension range of motion, and limb lengthening. CONCLUSION: Gait variability improved after total hip arthroplasty due to improved hip function. However, trunk variability was insufficient compared with that in healthy individuals.

Association between disease-specific anxiety at discharge and functional outcome in patients after total knee arthroplasty.

BACKGROUND: Patients who undergo total knee arthroplasty (TKA) may experience disease-specific problems, including decline in motor function and intense pain, which may result in disease-specific anxiety. This study aimed to investigate disease-specific anxiety at discharge, and any association between anxiety and functional outcomes following TKA. METHODS: The study prospectively included 129 patients who had undergone TKA. Each patient's disease-specific anxiety about wounds, pain, gait, and falling was assessed at discharge using a numerical rating scale, in which 0 represented no anxiety and 10 represented the highest level of anxiety. In addition, patient-reported outcomes (PROs) were evaluated using the Knee Society Score (KSS) at six-months postoperatively. The effects of disease-specific anxiety at discharge were evaluated with the KSS at six-months postoperatively and analyzed separately using multiple regression analysis. RESULTS: The median score for anxiety about wounds, pain, and gait was 4.0 (IQR 2.0-5.0) at discharge five days after surgery. The median score for anxiety about falling was also 4.0 (IQR 2.0-6.0). The level of anxiety regarding wounds, pain, gait, and falling was negatively associated with the KSS six-months postoperatively after adjusting for all confounding factors (wounds: ß = -2.8, 95% CI -4.3 to -1.3; pain: ß = -3.4, 95% CI -4.9 to -1.9; gait: ß = -4.3, 95% CI -5.8 to -2.9; falling: ß = -2.5, 95% CI -3.9 to -1.1). CONCLUSION: Patients reported similar levels of anxiety regarding wounds, pain, gait, and falling at discharge after TKA. The severity of anxiety symptoms at discharge was negatively associated with PROs six-months postoperatively.

Root mean square of lower trunk acceleration during walking in patients with unilateral total hip replacement.

Although several studies have described abnormal trunk motion before and after total hip arthroplasty (THA) surgery, few studies have examined trunk motion using accelerometry. The aim of this study was to determine whether abnormal trunk motion persisted after THA using accelerometry. A total of 24 female patients (61.0±6.9years) and 20 healthy female subjects (59.9±6.8years) participated in this study. Patients were assessed at 1 month prior to surgery and 12 months after surgery. Trunk acceleration during gait was measured using a triaxial accelerometer attached to the L3 spinous process. We calculated the root mean square (RMS) and RMS ratio (RMSR) in the vertical (VT), medio-lateral (ML), and anterior-posterior (AP) directions. Results revealed that the RMS in the VT and AP directions postoperatively was greater than that preoperatively, whereas there was no difference in the RMS in the ML direction. In addition, the preoperative RMSR in the ML direction was significantly greater compared with that of healthy individuals and the postoperative RMSR. There was no difference in the RMSR in the ML direction between healthy individuals and postoperatively. These findings suggested that the trunk motion in the frontal plane prior to surgery had improved and was comparable to that of healthy individuals following THA.

Factors Affecting Mobility after Knee Arthroplasty.

Restricted mobility is a major issue for individuals with knee osteoarthritis (OA). Total knee arthroplasty (TKA) is expected to improve mobility in people with knee OA by alleviating pain and improving walking ability. The present study aimed to describe the time course of mobility after TKA and to identify the factors affecting mobility after TKA. This prospective cohort study comprised 62 patients undergoing TKA, evaluated at 1 month preoperatively, as well as at 1, 3, and 6 months postoperatively. Outcome measures included mobility (Life Space Assessment; LSA), self-efficacy for walking tasks (modified Gait Efficacy Scale; mGES), and physical (quadriceps strength and the Timed Up and Go; TUG test) and knee function (the Knee Society Score questionnaire). As a result, a total of 59 patients (mean age: 71.7 years; range: 58-79 years) had completed all postoperative assessments. Compared with preoperative values, patients showed decreased LSA and mGES scores at 1 month postoperatively. We found improvements in those scores from the 1-month to the 3- and 6-month assessment; however, there was no difference in the LSA and mGES scores between the preoperative and 6-month assessment. We also found improvements in quadriceps strength, the TUG score, the Knee Society Score, and pain scores from the preoperative to the 6-month assessment. Additionally, at 6 months postoperatively, the mGES and TUG scores significantly affected mobility. Our results suggest that mobility at 6 months after TKA is similar to preoperative level and self-efficacy for walking tasks and functional ability are important factors in improving mobility after TKA.

Effects of Group-Based Exercise on Range of Motion, Muscle Strength, Functional Ability, and Pain During the Acute Phase After Total Knee Arthroplasty: A Controlled Clinical Trial.

Study Design Prospective observational study including a historical control group. Background The extent to which group-based exercise (G-EXE) improves knee range of motion (ROM), quadriceps strength, and gait ability is similar to that of individualized exercise (I-EXE) at 6 weeks and 8 months after total knee arthroplasty (TKA). However, the benefits of G-EXE for patients during the acute recovery phase after TKA remain unclear. Objective To determine the effects of G-EXE during the acute recovery phase after TKA on knee ROM, quadriceps strength, functional ability, and knee pain. Methods Two hundred thirty-one patients participated in G-EXE in addition to regular ambulation and activities-of-daily-living exercises twice daily during the hospital stay. Outcomes were compared to those of a retrospectively identified, historical control group (I-EXE group [n = 206]) that included patients who performed exercises identical to those performed by the G-EXE group. The outcomes included knee ROM, quadriceps strength, pain intensity, and timed up-and-go test score at 1 month before surgery and at discharge. Analyses were adjusted for age, body mass index, sex, length of hospital stay, and preoperative values. Results Changes in ROM of knee flexion and extension (P<.001) and quadriceps strength (P<.001) were significantly better in the G-EXE group than those in the I-EXE group at discharge. The pain intensity improved more in the G-EXE group than in the I-EXE group at discharge (P<.001). However, the changes in the timed up-and-go scores were not significantly different. Conclusion Patients performing G-EXE in addition to regular ambulation and activities-of-daily-living exercises demonstrated greater changes in knee ROM, quadriceps strength, and knee pain than those performing I-EXE in addition to regular ambulation and activities-of-daily-living exercises. The nonrandomized, asynchronous design decreases certainty of these findings. Level of Evidence Therapy, level 2b. J Orthop Sports Phys Ther 2016;46(9):742-748. Epub 5 Aug 2016. doi:10.2519/jospt.2016.6409.

Laparoscopic radical right hemicolectomy for cecal cancer and middle colic artery aneurysm.

BACKGROUND: Middle colic artery (MCA) aneurysms are very rare and exclusively reported with symptoms or rupture. We report successful laparoscopic elective surgery for both cecal cancer and MCA aneurysm in an 87-year-old man who presented with bloody stools. METHODS: Diagnostic colonoscopy revealed a cecal tumor 40 mm in diameter that was histologically confirmed as a well-differentiated adenocarcinoma. The three-phase dynamic computed tomography showed a cecal tumor without any metastasis and an MCA aneurysm 10 mm in diameter. Radical right hemicolectomy with D3 lymph node dissection that included the MCA aneurysm was performed. The postoperative course was uneventful, and the patient survived without recurrence. CONCLUSIONS: Even though the present patient was very elderly, the postoperative course of laparoscopic radical surgery for both an MCA aneurysm and cecal cancer was uneventful with good short-term outcomes.

Gait variability before surgery and at discharge in patients who undergo total knee arthroplasty: a cohort study.

This study aimed to determine gait ability at hospital discharge in patients undergoing total knee arthroplasty (TKA) as an indicator of the risk of falling. Fifty-seven patients undergoing primary TKA for knee osteoarthritis participated in this study. Gait variability measured with accelerometers and physical function including knee range of motion (ROM), quadriceps strength, walking speed, and the Timed Up and Go (TUG) test were evaluated preoperatively and at discharge from the hospital (1 month before and 5 days after surgery). All patients were discharged directly home at 5 days after surgery. Knee flexion of ROM, quadriceps strength, walking speed, and the TUG test results were significantly worse at hospital discharge than preoperatively (p < 0.001). However, gait variability was not significantly different before and after TKA. This result indicated that patients following TKA surgery could walk at hospital discharge as stably as preoperatively regardless of the decrease in physical function, including knee ROM, quadriceps strength, and gait speed after surgery.

Impact of D3 lymph node dissection on survival for patients with T3 and T4 colon cancer.

PURPOSE: The clinical significance of D3 lymph node dissection for patients with colon cancer remains controversial. This study aims to clarify the impact of D3 lymph node dissection on survival in patients with colon cancer. METHODS: This is a retrospective cohort study from a prospectively registered multi-institutional database of colorectal cancer in Japan. Propensity score matching method was applied to balance potential confounders of the treatment. A cohort of 10,098 patients who underwent radical colectomy for pT3 and pT4 colon cancer between 1985 and 1994 were identified. A total of 3,425 propensity score matched pairs were extracted from the entire cohort. The primary outcome measure was overall survival (OS). RESULTS: In the entire cohort, there was a statistically significant difference in overall survival (OS) between the patients who had D3 and D2 lymph node dissection (p = 0.00003). The estimated hazard ratio (HR) for OS of patients who had D3 versus D2 lymph node dissection was 0.827 (95 % confidence interval, 0.757 to 0.904). In the matched cohort, there was also a significant difference in OS between the two groups (p = 0.0001), and the estimated HR for OS was 0.814 (95 % confidence interval, 0.734 to 0.904). CONCLUSIONS: We found D3 lymph node dissection for pT3 and pT4 colon cancer to be associated with a significant survival advantage in a large-scale database, even after adjusting potential confounders of lymph node dissection. This finding may provide a rationale for D3 lymph node dissection in radical surgery for pT3 and pT4 colon cancer.

Cyclin D1 harboring the T286I mutation promotes oncogenic activation in endometrial cancer.

Cyclin D1 is an important regulator of cell cycle progression. Phosphorylation of cyclin D1 at Thr286 by GSK3ß triggers its nuclear export and cytoplasmic proteolysis via the 26S proteasome. Cyclin D1 overexpression is a common event in various types of human cancers; however, reports of mutations are extremely rare. We analyzed mutations of the cyclin D1 gene, CCND1, in 88 endometrial cancer tissue specimens and detected mutations in 2 cases (2.3%). Both were unreported mutations with substitution of threonine to isoleucine at codon 286 (T286I). These two tumors harbored coexisting mutations in K-ras, PIK3CA and/or PTEN and showed accumulation of cyclin D1 in the nucleus by immunohistochemistry. Furthermore, we analyzed the functions of mutant cyclin D1 (T286I) by luciferase assays, immunofluorescence, western blotting and clonogenic cell survival assays in HEK-293T cells. We found that exogenous mutant cyclin D1 (T286I) accumulated in the nuclei in HEK-293T cells, and that it inhibited the expression of pRb. Additionally, the number of colonies was increased by introduction of mutant cyclin D1 (T286I) compared to that of wild-type cyclin D1. In conclusion, we identified an unreported CCND1 mutation (T286I) in two endometrial cancers and revealed that the mutation was functional for inducing cell proliferation in human cells.