Triple primary lung cancer: a case report.

BACKGROUND: The risk of developing lung cancer is increased in smokers, patients with chronic obstructive pulmonary disease, individuals exposed to environmental carcinogens, and those with a history of lung cancer. Automobile exhaust fumes containing carcinogens are a risk factor for lung cancer. However, we go through life unaware of the fact that automobile exhaust is the cause of cancer. Especially, in lung cancer patient, it is important to search out pre-existing risk factors and advice to avoid them, and monitor carefully for recurrence after treatment. CASE PRESENTATION: This is the first report of a case with triple lung cancers with different histologic types at different sites, observed in a 76-year-old parking attendant. The first adenocarcinoma and the second squamous cell carcinoma were treated with stereotactic radiosurgery because the patient did not want to undergo surgery. Although the patient stopped intermittent smoking after the diagnosis, he continued working as a parking attendant in the parking lot. After 29 months from the first treatment, the patient developed a third new small cell lung cancer; he was being treated with chemoradiation. CONCLUSIONS: New mass after treatment of lung cancer might be a multiple primary lung cancer rather than metastasis. Thus, precision evaluation is important. This paper highlights the risk factors for lung cancer that are easily overlooked but should not be dismissed, and the necessity of discussion with patients for the surveillance after lung cancer treatment. We should look over carefully the environmental carcinogens already exposed, and counsel to avoid pre-existing lung cancer risk factors at work or residence in patients with lung cancer.

Role of the WNT/ß-catenin/ZKSCAN3 Pathway in Regulating Chromosomal Instability in Colon Cancer Cell lines and Tissues.

Zinc finger protein with KRAB and SCAN domains 3 (ZKSCAN3) acts as an oncogenic transcription factor in human malignant tumors, including colon and prostate cancer. However, most of the ZKSCAN3-induced carcinogenic mechanisms remain unknown. In this study, we identified ZKSCAN3 as a downstream effector of the oncogenic Wnt/ß-catenin signaling pathway, using RNA sequencing and ChIP analyses. Activation of the Wnt pathway by recombinant Wnt gene family proteins or the GSK inhibitor, CHIR 99021 upregulated ZKSCAN3 expression in a ß-catenin-dependent manner. Furthermore, ZKSCAN3 upregulation suppressed the expression of the mitotic spindle checkpoint protein, Mitotic Arrest Deficient 2 Like 2 (MAD2L2) by inhibiting its promoter activity and eventually inducing chromosomal instability in colon cancer cells. Conversely, deletion or knockdown of ZKSCAN3 increased MAD2L2 expression and delayed cell cycle progression. In addition, ZKSCAN3 upregulation by oncogenic WNT/ß-catenin signaling is an early event of the adenoma-carcinoma sequence in colon cancer development. Specifically, immunohistochemical studies (IHC) were performed using normal (NM), hyperplastic polyps (HPP), adenomas (AD), and adenocarcinomas (AC). Their IHC scores were considerably different (61.4 in NM; 88.4 in HPP; 189.6 in AD; 246.9 in AC). In conclusion, ZKSCAN3 could be responsible for WNT/ß-catenin-induced chromosomal instability in colon cancer cells through the suppression of MAD2L2 expression.

Noninvasive assessment of hepatic sinusoidal obstructive syndrome using acoustic radiation force impulse elastography imaging: A proof-of-concept study in rat models.

OBJECTIVES: To determine the feasibility of acoustic radiation force impulse (ARFI) elastography in the evaluation of hepatic sinusoidal obstruction syndrome (SOS) in rat models. METHODS: Rat SOS models of various severities were created by monocrotaline gavage (n = 40) or by intraperitoneal injection of 5-fluorouracil, leucovorin and oxaliplatin (FOLFOX) (n = 16). Liver shear-wave velocity (SWV) was measured using ARFI elastography. Liver samples were analysed for the SOS score, steatosis, lobular inflammation and fibrosis. RESULTS: The liver SWV was significantly elevated in the SOS models (1.29-2.24 m/s) compared with that of the matched control rats (1.01-1.09; p≤.09; veFor seven FOLFOX-treated rats which were longitudinally followed-up, the liver SWV significantly increased at 7 weeks (1.32±0.13 m/s) compared with the baseline (1.08±0.1 m/s, p=.015) and then significantly declined after a 2-week, treatment-free period (1.15±0.13 m/s; p=.048). Multivariate analysis revealed that the SOS score (p<.001) and lobular inflammation (p=.044) were independently correlated with the liver SWV. CONCLUSION: Liver SWV is elevated in SOS in proportion to the degree of sinusoidal injury and lobular inflammation in rat SOS models. ARFI elastography has potential as an examination for diagnosis, severity assessment and follow-up of SOS. KEY POINTS: • Liver SWV using ARFI elastography was significantly elevated in SOS rat. • Sinusoidal injury and lobular inflammation grades had correlation with liver SWV. • ARFI elastography has potential for diagnosis, severity assessment, and follow-up of SOS.

BK virus-associated nephropathy with hydronephrosis in a patient with AIDS: a case report and literature review.

BK virus is ubiquitous worldwide, with infection usually occurring in early childhood. BK virus replicates prolifically under immunosuppressive conditions, causing inflammation along the genitourinary tract and progressing clinically to hemorrhagic cystitis, ureteral stenosis, and tubulointerstitial nephritis. Most BK virusassociated nephropathy occurs in renal allograft patients after kidney transplantation, although some case reports have described BK virus-associated nephropathy in the native kidney, particularly in patients with human immunodeficiency virus infection. Here we present the case of a 49-year-old male with acquired immunodeficiency syndrome (AIDS) and renal dysfunction with hydronephrosis. The renal biopsy showed tubulointerstitial nephritis with lymphoplasmacytic infiltrates and intranuclear inclusions in the tubular epithelium, which are typical findings for BK virus-associated nephropathy. In addition, immunohistochemical staining revealed that the SV40 large T antigen exhibited a nuclear localization in tubular cells. To the best of our knowledge, this is the first case report of BK virus-associated nephropathy combined with hydronephrosis that was diagnosed by biopsy in a patient with AIDS.

Genomic evidence of reactive oxygen species elevation in papillary thyroid carcinoma with Hashimoto thyroiditis.

Elevated levels of reactive oxygen species (ROS) have been proposed as a risk factor for the development of papillary thyroid carcinoma (PTC) in patients with Hashimoto thyroiditis (HT). However, it has yet to be proven that the total levels of ROS are sufficiently increased to contribute to carcinogenesis. We hypothesized that if the ROS levels were increased in HT, ROS-related genes would also be differently expressed in PTC with HT. To find differentially expressed genes (DEGs) we analyzed data from the Cancer Genomic Atlas, gene expression data from RNA sequencing: 33 from normal thyroid tissue, 232 from PTC without HT, and 60 from PTC with HT. We prepared 402 ROS-related genes from three gene sets by genomic database searching. We also analyzed a public microarray data to validate our results. Thirty-three ROS related genes were up-regulated in PTC with HT, whereas there were only nine genes in PTC without HT (Chi-square p-value < 0.001). Mean log2 fold changes of up-regulated genes was 0.562 in HT group and 0.252 in PTC without HT group (t-test p-value = 0.001). In microarray data analysis, 12 of 32 ROS-related genes showed the same differential expression pattern with statistical significance. In gene ontology analysis, up-regulated ROS-related genes were related with ROS metabolism and apoptosis. Immune function-related and carcinogenesis-related gene sets were enriched only in HT group in Gene Set Enrichment Analysis. Our results suggested that ROS levels may be increased in PTC with HT. Increased levels of ROS may contribute to PTC development in patients with HT.

Bone involvement in secondary syphilis: a case report and systematic review of the literature.

Bone involvement is an unusual manifestation of secondary syphilis, but little information is available in the English-language literature. We carried out a systematic review of the English-language literature from 1964 to 2013, describing cases of secondary syphilis with bone involvement. We also describe a case of secondary syphilis with multiple osteolytic lesions, mimicking metastatic cancer or myeloma, which was included in an analysis of 37 eligible cases of secondary syphilis with bone involvement. Of these 37 patients, 28 (76%) patients were male, and the median age was 32 years (range, 12-64 years). Eleven (30%) patients had human immunodeficiency virus (HIV) infection with a median CD4 lymphocyte count of 343 cells/mm (range, 130-689 cells/mm). The diagnosis of early syphilis was suspected based on mucocutaneous findings in 28 (76%) cases. In the remaining 9 (24%) cases, high titers of nontreponemal serologic tests were the only evidence of early syphilis. The median venereal disease research laboratory (VDRL) titer was 1:64 (range, 1:8-1:320), and median rapid plasma reagin (RPR) titer was 1:64 (range, 1:16-1:512). The bones most often affected were long bones of the limbs (n = 22) and skull (n = 21). The bone lesions were multifocal in 27 (73%) cases and osteolytic in 19 (51%) cases. The treatment of syphilitic bone lesions was medical only in most patients, and prognosis was favorable with high-dose penicillin therapy. Clinical features and outcome between HIV-uninfected and HIV-infected patients were not different. Knowledge of this rare entity may lead to early diagnosis and appropriate management.

Febuxostat ameliorates diabetic renal injury in a streptozotocin-induced diabetic rat model.

BACKGROUND: Oxidative stress and inflammation are known to play central roles in the development of diabetic nephropathy (DN). Febuxostat is a novel non-purine xanthine oxidase (XO)-specific inhibitor developed to treat hyperuricemia. In this study, we investigated whether febuxostat could ameliorate DN via renoprotective mechanisms such as alleviation of oxidative stress and anti-inflammatory actions. METHODS: Male Sprague-Dawley rats were divided into three groups: a normal group, a diabetes group (DM group), and a febuxostat-treated diabetes group (DM+Fx group). We administered 5 mg/kg of febuxostat to experimental rats for 7 weeks and evaluated clinical and biochemical parameters and XO and xanthine dehydrogenase (XDH) activity in hepatic tissue. The degree of oxidative stress and extent of inflammation were evaluated from urine samples and renal tissue collected from each group. RESULTS: Diabetic rats (DM and DM+Fx groups) had higher blood glucose and kidney weight relative to body weight than normal rats. Albuminuria was significantly reduced in febuxostat-treated diabetic rats compared with untreated diabetic rats. Quantitative analysis showed that hepatic XO and XDH activities were higher in the DM groups, but decreased after treatment with febuxostat. Urinary 8-OHdG concentrations and renal cortical nitrotyrosine also indicated reduced oxidative stress in the DM+Fx group relative to the DM group. The number of ED-1-stained cells in the glomerulus and tubule of diabetic renal tissue decreased in febuxostat-treated diabetic rats relative to that of non-treated diabetic rats. Diabetic rats also expressed higher transcript levels of inflammatory genes (E-selectin and VCAM-1), an inflammation-induced enzyme (COX-2), and inflammatory mediators (ED-1 and NF-κB) than control rats; expression of these genes was significantly reduced by treatment with febuxostat. CONCLUSIONS: Febuxostat prevents diabetic renal injury such as albuminuria. This renoprotective effect appears to be due to attenuation of the inflammatory and oxidative effects of diabetes-induced renal damage through inhibition of XO and XDH activities.

Sonographic findings in a case of scrotal lymphangioma.

The scrotum is an extremely rare site for lymphangioma. We report the case of a scrotal lymphangioma in a 20-year-old male patient who developed painless scrotal swelling. Typical sonography and MRI findings are shown. Surgical excision and histopathology confirmed the diagnosis.

Association of C1q deposition with renal outcomes in IgA nephropathy.

BACKGROUND/AIMS: IgA nephropathy (IgAN) is characterized by a highly variable clinical course. It has been reported that histopathologic lesions are risk factors for the progression of IgAN. The aim of this study was to investigate the relationships between co-deposition of C1q, clinicopathological features, and renal outcomes in patients with IgAN. METHODS: This retrospective cohort study included 221 patients with primary IgAN who underwent renal biopsy at the Kyung Hee University Medical Center from January 1996 to December 2008. Patients were divided in two groups: C1qpositive and C1q-negative. Using propensity scores to minimize confounding factors, we selected 36 matched C1q-negative patients from among the 203 unmatched C1q-negative patients and compared them with the 18 C1q-positive patients. We evaluated baseline characteristics and the severity of histologic lesions. We expressed the average rate of monthly renal function decline as the slope of eGFR (ΔGFR/M). RESULTS: 18 patients with IgAN showed mesangial deposition of C1q (8.1%). The C1q-positive patients had higher mean systolic blood pressure values and more impaired renal function than the unmatched C1q-negative patients. However, this association was not seen when the C1qpositive patients were compared with the matched C1q-negative patients. The slope of eGFR (ΔeGFR/M) declined steeply in the C1q-positive group. The incidence of severe cases of tubulointerstitial inflammation (TII) and fibrosis (TIF) was also greater in the C1q-positive group than the unmatched C1qnegative group, while only the incidence of severe TIF was significantly greater in the C1q-positive group than the matched C1qnegative group. Biopsies from C1q-positive patients showed more intense IgA staining as well as positive rates of IgG and IgM staining than those of unmatched C1q-negative patients. However, compared with the matched C1q-negative group, only the IgG positive rate was significantly higher in the C1q-positive patients. Multiple regression analysis of C1q-positive and matched C1q-negative patients revealed that C1q deposition was a critical determinant of a poorer renal prognosis. CONCLUSIONS: Mesangial C1q deposition in the glomerulus is associated with a poor renal outcome and severe pathologic features in patients with IgAN. The deposition of C1q in IgAN could therefore serve as an indicator of a poor renal prognosis.

Quantitative proteomic analysis of bronchoalveolar lavage fluids from patients with small cell lung cancers.

PURPOSE: Small cell lung cancer (SCLC) is one of the malignant cancers with aggressive progression and poor prognosis. Bronchoalveolar lavage fluid (BALF) has been arising recently as a potential source of biomarkers for lung cancers. In this study, we performed quantitative BALF proteomic analysis to identify potential biomarkers for SCLC. EXPERIMENTAL DESIGN: BALF were collected from tumor-bearing lungs and non-tumor lungs of five SCLC patients. Then, BALF proteomes were prepared for a TMT-based quantitative mass spectrometry analysis. Differentially expressed proteins (DEP) were identified when considering individual variation. Potential SCLC biomarker candidates were validated by immunohistochemistry (IHC). A public database of multiple SCLC cell lines was used to evaluate the correlation of these markers with SCLC subtypes and chemo-drug responses. RESULTS: We identified 460 BALF proteins in SCLC patients and observed considerable individual variation among the patients. Immunohistochemical analysis and bioinformatics resulted in the identification of CNDP2 and RNPEP as potential subtype markers for ASCL1 and NEUROD1, respectively. In addition, CNDP2 was found to be positively correlated with responses to etoposide, carboplatin, and irinotecan. CONCLUSIONS AND CLINICAL RELEVANCE: BALF is an emerging source of biomarkers, making it useful for the diagnosis and prognosis of lung cancers. We characterized the proteomes of paired BALF samples collected from tumor-bearing and non-tumor lungs of SCLC patients. Several proteins were found elevated in tumor-bearing BALF, and especially CNDP2 and RNPEP appeared to be potential indicators for ASLC1-high and NEUROD1-high subtypes of SCLC, respectively. The positive correlation of CNDP2 with chemo-drug responses would help to make decisions for treatment of SCLC patients. These putative biomarkers could be comprehensively investigated for a clinical use towards precision medicine.

Clinicopathologic features of intraductal papillary neoplasm of the bile duct according to histologic subtype.

OBJECTIVES: Despite an increase in the reports of intraductal papillary neoplasm of the bile duct (IPN-B), the clinical characteristics and long-term prognosis of this disease are not well known compared with those of intraductal papillary mucinous neoplasms of the pancreas. The objective of our study was to compare the clinical features, radiologic findings, and clinical outcomes of IPN-B according to histologic subtype. METHODS: A retrospective analysis was performed on the medical records of 97 patients diagnosed with IPN-B by pathologic analysis of their surgical specimens between May 1995 and May 2010. We compared the clinical manifestations, radiological findings, pathologic grade, curative resection rate, recurrence, and overall survival according to four histologic subtypes: gastric (n=15), intestinal (n=46), pancreaticobiliary (n=33), and oncocytic (n=3), which were classified on the basis of hematoxylin and eosin staining and the immunohistochemical profile of mucin core proteins. RESULTS: Mucin hypersecretion was significantly more frequent in patients with gastric and intestinal types than it was in those with oncocytic and pancreaticobiliary types (P=0.014). There were no significant differences between groups regarding the presence of bile duct stones or tumor location. The frequency of invasive carcinoma in the pancreaticobiliary type was significantly higher than those in the gastric and intestinal types (72.7 vs. 26.7 and 32.6%, P<0.001 and P<0.001). When comparing the survival curves according to histologic subtype, patients with pancreaticobiliary type demonstrated significantly worse survival compared to those with gastric and intestinal types (P=0.035). CONCLUSIONS: Gastric and intestinal types of IPN-B have similar clinical characteristics compared with the pancreaticobiliary type, which has a worse prognosis.

ERCC1 as a biomarker for bladder cancer patients likely to benefit from adjuvant chemotherapy.

BACKGROUND: The role of adjuvant chemotherapy and the value of molecular biomarkers in bladder cancer have not been determined. We aimed to assess the predictive and prognostic values of excision repair cross-complementation 1 (ERCC1) in identifying appropriate patients who may potentially benefit from adjuvant chemotherapy for bladder cancer. METHODS: A retrospective analysis was performed on 93 patients with completely resected transitional cell carcinoma of the bladder. ERCC1 expression was assessed by immunohistochemistry. ERCC1 expression was analyzed in 57 patients treated with adjuvant gemcitabine plus cisplatin chemotherapy and 36 who were not treated. RESULTS: Among 93 patients, ERCC1 expression was positive in 54 (58.1%) and negative in 39 (41.9%). ERCC1 positivity was significantly associated with longer survival (adjusted hazard ratio for death, 0.12, 95% confidence interval [CI] 0.014-0.99; P = 0.049) in the group without adjuvant chemotherapy while ERCC1 positivity was associated with shorter survival among patients who have received adjuvant chemotherapy (adjusted hazard ratio for death, 2.64; 95% CI 1.01-6.85; P = 0.047). Therefore, clinical benefit from adjuvant chemotherapy was associated with ERCC1 negativity as measured by overall survival (test for interaction, P = 0.034) and by disease-free survival (test for interaction, P = 0.20). CONCLUSIONS: Among patients with completely resected transitional cell carcinoma of the bladder, those with ERCC1-negative tumors seemed to benefit more from adjuvant gemcitabine plus cisplatin chemotherapy than those with ERCC1-positive tumors. Future prospective, randomized studies are warranted to confirm our findings.

Reappraisal of KIT mutation in adenoid cystic carcinomas of the salivary gland.

BACKGROUND: While overexpression of KIT protein has been well documented in adenoid cystic carcinomas (ACCs), mutation of KIT gene has been a controversial issue. We wanted to evaluate clinical value of the KIT mutation and protein expression in ACC. METHODS: We analyzed 33 cases of ACC. Gene mutations in KIT exons 9, 11, 13, and 17 were analyzed using paraffin-embedded tissue, and two different sets of primers with direct sequencing after polymerase chain reaction (PCR) for exon 9, 11, 13, and 17, and cloning of PCR products for exon 11. KIT protein expression was assessed by immunohistochemistry. The correlation between clinicopathological findings and these biomarkers was analyzed. RESULTS: No KIT mutation was observed in all of the 33 cases. With one primer set, KIT mutation was found in nine of 33 cases (27.3%). However, these mutations were not reproducible in the experiment using another primer set. KIT protein overexpression was detected in 22 of 33 patients (66.7%). KIT protein expression was not statistically correlated with either clinicopathological factors or survival. Patients with metastasis showed a tendency of longer progression-free survival (P = 0.052) and overall survival (P = 0.080) when the tumor overexpressed KIT protein. CONCLUSION: This study supports that mutational study using paraffin-embedded tissue should be interpreted with great caution. KIT gene mutation is very rare in ACC, and gene mutation is not the cause of protein overexpression. KIT protein expression may have a potential value for better prognostic factor in patients with metastasis.

Body mass index and outcome of ASC-H-interpreted cervical smears in postmenopausal women.

OBJECTIVE: Patient age is one important factor used to evaluate the risk in women with ASC-H (atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion). This finding may be associated with atrophic changes reflecting a hypoestrogenic status and suggests that body mass index (BMI) can affect the outcome of ASC-H smears in postmenopausal women. STUDY DESIGN: We investigated the outcome of 154 postmenopausal women with an ASC-H smear and assessed relationships with BMI categories and serum estradiol levels. RESULTS: In patients with higher BMI, an underlying squamous intraepithelial lesion (SIL) was more frequent than in patients with lower BMI, and a higher BMI was also associated with increased serum estradiol levels. When samples were classified by preparation method, these findings were more pronounced in liquid-based smears than in conventional smears. Principal component analysis using three factors (BMI, age and human papilloma virus status) revealed two distinct groups: those with a negative cervical smear and those with a smear result indicating SIL+. CONCLUSION: Hormonal alterations can affect the outcome of ASC-H smears, and BMI is one factor that should be considered when evaluating the risk associated with ASC-H smears in postmenopausal women.

High Tumor Mutation Burden Is Associated with Poor Clinical Outcome in EGFR-Mutated Lung Adenocarcinomas Treated with Targeted Therapy.

This study aimed to determine the association between TMB and treatment outcomes in patients with epidermal growth factor receptor (EGFR)-mutated lung cancer that were treated with tyrosine kinase inhibitors (TKIs). The TMB was assessed using a 409-gene targeted next-generation sequencing panel. We compared the response rate (RR), progression-free survival (PFS), overall survival (OS), and frequency of secondary T790M mutations among the different TMB groups. The median TMB of the study population (n = 88) was 3.36/megabases. We divided 52 (59%) and 36 (41%) patients into the low and high TMB groups, respectively. A high TMB level was significantly associated with liver metastasis and more advanced stage (all p < 0.05). RR was significantly lower in the high TMB group than that of the low TMB group (50.0% vs. 80.7%, all p = 0.0384). In multivariate analysis, high TMB was independently associated with a shorter PFS (hazard ratio [HR] = 1.80, p = 0.0427) and shorter OS (HR = 2.05, p = 0.0397) than that of the low TMB group. Further, high TMB was independently associated with decreased T790M mutation development. These results suggest that high TMB may be a predictive biomarker for adverse treatment outcomes and represent a patients' subgroup warranting tailored therapeutic approaches.

Pulmonary Metastasizing Low-Grade Endometrial Stromal Sarcoma: Case Report and Review of Diagnostic Pitfalls.

Pulmonary manifestations of benign metastasizing leiomyoma (BML) usually include multiple well-defined, round, bilateral nodules. Low-grade endometrial stromal sarcoma (LG-ESS) is a rare uterine tumor. A 70-year-old woman visited the clinic complaining of acute cough and dyspnea in April 2017. Chest computed tomography (CT) revealed pneumothorax and multiple pulmonary nodules. She had a history of hysterectomy for uterine leiomyoma 23 years ago. Biopsy revealed that the pulmonary masses were consistent with BML. However, the patient had two subsequent episodes of acute, recurrent respiratory distress, accompanied by massive pleural effusions and hydropneumothorax over the next two years. A chest CT performed for acute dyspnea revealed large and multiple hydropneumothoraces. The size and distribution of pulmonary masses were aggravated along with cystic changes and bilateral pleural effusions. Given this aggressive feature, additional immunohistochemical findings and gynecologic pathologist review confirmed the correct diagnosis to be LG-ESS. After initiating anti-estrogen therapy, the patient achieved a partial response, without recurrence of symptoms, for 28 months. Metastatic LG-ESS responds well to anti-hormonal therapy. If the clinical pattern of a disease is different than expected, the possibility of a correction in the diagnosis should be considered.

Clinicopathologic and Genetic Features of Primary T-cell Lymphomas of the Central Nervous System: An Analysis of 11 Cases Using Targeted Gene Sequencing.

Primary central nervous system lymphoma (PCNSL) of peripheral T-cell lineage (T-PCNSL) is rare, and its genetic and clinicopathologic features remain unclear. Here, we present 11 cases of T-PCNSL in immunocompetent individuals from a single institute, focusing on their genetic alterations. Seven cases were subject to targeted panel sequencing covering 120 lymphoma-related genes. Nine of the eleven cases were classified as peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), of which one was of γδT-cell lineage. There was one case of anaplastic lymphoma kinase-positive anaplastic large cell lymphoma and another of extranodal natural killer (NK)/T-cell lymphoma (ENKTL) of αßT-cell lineage. The male to female ratio was 7 : 4 and the age ranged from 3 to 75 years (median, 61 y). Most patients presented with neurological deficits (n=10) and showed multifocal lesions (n=9) and deep brain structure involvement (n=9). Tumor cells were mostly small-to-medium, and T-cell monoclonality was detected in all nine evaluated cases. PTCL-NOS was CD4-positive (n=4), CD8-positive (n=3), mixed CD4-positive and CD8-positive (n=1), or CD4/CD8-double-negative (n=1, γδT-cell type). Cytotoxic molecule expression was observed in 4 (67%) of the 6 evaluated cases. Pathogenic alterations were found in 4 patients: one PTCL-NOS case had a frameshift mutation in KMT2C, another PTCL-NOS case harbored a truncating mutation in TET2, and another (γδT-cell-PTCL-NOS) harbored NRAS G12S and JAK3 M511I mutations, and homozygous deletions of CDKN2A and CDKN2B. The ENKTL (αßT-cell lineage) case harbored mutations in genes ARID1B, FAS, TP53, BCOR, KMT2C, POT1, and PRDM1. In conclusion, most of the T-PCNSL were PTCL-NOS, but sporadic cases of other subtypes including γδT-cell lymphoma, anaplastic lymphoma kinase-positive anaplastic large cell lymphoma, and ENKTL were also encountered. Immunophenotypic analysis, clonality test, and targeted gene sequencing along with clinicoradiologic evaluation, may be helpful for establishing the diagnosis of T-PCNSL. Moreover, this study demonstrates genetic alterations with potential diagnostic and therapeutic utility in T-PCNSL.