Anti-anhedonic effect of selective serotonin reuptake inhibitors with affinity for sigma-1 receptors in picrotoxin-treated mice

BACKGROUND AND PURPOSE

Prefrontal dopamine release by the combined activation of 5-HT1A and sigma-1 (σ1 ) receptors is enhanced by the GABAA receptor antagonist picrotoxin in mice. Here, we examined whether this neurochemical event was accompanied by behavioural changes.

EXPERIMENTAL APPROACH

Male mice were treated with picrotoxin to decrease GABAA receptor function. Their anhedonic behaviour was measured using the female encounter test. The expression of c-Fos was determined immunohistochemically.

KEY RESULTS

Picrotoxin caused an anxiogenic effect on three behavioural tests, but it did not affect the immobility time in the forced swim test. Picrotoxin decreased female preference in the female encounter test and attenuated the female encounter-induced increase in c-Fos expression in the nucleus accumbens. Picrotoxin-induced anhedonia was ameliorated by fluvoxamine and S-(+)-fluoxetine, selective serotonin reuptake inhibitors with high affinity for the σ1 receptor. The effect of fluvoxamine was blocked by a 5-HT1A or a σ1 receptor antagonist, and co-administration of the σ1 receptor agonist (+)-SKF-10047 and the 5-HT1A receptor agonist osemozotan mimicked the effect of fluvoxamine. By contrast, desipramine, duloxetine and paroxetine, which have little affinity for the σ1 receptor, did not affect picrotoxin-induced anhedonia. The effect of fluvoxamine was blocked by a dopamine D2/3 receptor antagonist. Methylphenidate, an activator of the prefrontal dopamine system, ameliorated picrotoxin-induced anhedonia.

CONCLUSION AND IMPLICATIONS

Picrotoxin-treated mice show anhedonic behaviour that is ameliorated by simultaneous activation of 5-HT1A and σ1 receptors. These findings suggest that the increased prefrontal dopamine release is associated with the anti-anhedonic effect observed in picrotoxin-treated mice.

Successful Treatment of Catastrophic Antiphospholipid Antibody Syndrome Associated with MALT Lymphoma by Autologous Hematopoietic Stem Cell Transplantation

A 37-year-old woman with extranodal marginal-zone lymphoma was admitted with a fever, hemiplegia, and severe dyspnea after chemotherapy. Catastrophic antiphospholipid antibody syndrome (CAPS) was suspected based on the histopathological confirmation of small-pulmonary vessel occlusion, evidence of the involvement of three organs, and elevated lupus anticoagulant assay results in a short time span. The patient responded to the initial treatment. One month later, the CAPS and lymphoma relapsed, and the patient underwent autologous hematopoietic stem cell transplantation. Complete remission of the lymphoma has been successfully maintained, and the condition of the patient has remained stable for two years with no further evidence of thrombosis.

Effects of Positive Pressure in Odontogenic Keratocysts

Intracystic fluid pressure is thought to be involved in odontogenic cyst growth. In this study, we investigated the effects of positive pressure on the expression of interleukin-1α (IL-1α), matrix metalloproteinases (MMPs), and prostaglandin E2 (PGE2) in odontogenic keratocysts to determine whether this pressure stimulates inflammatory cytokine production and signaling of osteoclastogenic events. Positive pressure enhanced the expression of IL-1α mRNA and protein in odontogenic keratocyst epithelial cells, and increased the secretion of MMP-1, MMP-2, MMP-3, and PGE2 in a co-culture of odontogenic keratocyst fibroblasts and the epithelial cells. The pressure-induced secretions were inhibited by an interleukin-1 receptor antagonist. Recombinant human interleukin-1α (rhIL-1α) increased the secretion of MMP-1, MMP-2, MMP-3, and PGE2 in the fibroblasts. Furthermore, in the fibroblasts, rhIL-1α enhanced the expression of macrophage colony-stimulating factor (M-CSF) mRNA, and rhIL-1α-induced PGE2 increased the expression of nuclear factor κB ligand (RANKL) mRNA. Thus, positive pressure may play a crucial role in odontogenic keratocyst growth via stimulating the expression of IL-1α in epithelial cells.

Principal component analysis uncovers cytomegalovirus-associated NK cell activation in Ph+ leukemia patients treated with dasatinib

Dasatinib treatment markedly increases the number of large granular lymphocytes (LGLs) in a proportion of Ph⁺ leukemia patients, which associates with a better prognosis. The lymphocytosis is predominantly observed in cytomegalovirus (CMV)-seropositive patients, yet detectable CMV reactivation exists only in a small fraction of patients. Thus, etiology of the lymphocytosis still remains unclear. Here, we identified NK cells as the dominant LGLs expanding in dasatinib-treated patients, and applied principal component analysis (PCA) to an extensive panel of NK cell markers to explore underlying factors in NK cell activation. PCA displayed phenotypic divergence of NK cells that reflects CMV-associated differentiation and genetic differences, and the divergence was markedly augmented in CMV-seropositive dasatinib-treated patients. Notably, the CMV-associated highly differentiated status of NK cells was already observed at leukemia diagnosis, and was further enhanced after starting dasatinib in virtually all CMV-seropositive patients. Thus, the extensive characterization of NK cells by PCA strongly suggests that CMV is an essential factor in the NK cell activation, which progresses stepwise during leukemia and subsequent dasatinib treatment most likely by subclinical CMV reactivation. This study provides a rationale for the exploitation of CMV-associated NK cell activation for treatment of leukemias.

Chronic GVHD complicated with polymyositis and cardiomyopathy after myeloablative hematopoietic stem cell transplantation

A 50-year-old woman presented with leukocytosis, anemia, and thrombocytopenia in June 2013. She was diagnosed with de novo acute myeloid leukemia with the t(16;21)(q24;q22) translocation. She received an allogeneic hematopoietic stem cell transplant from an HLA-DRB1 locus-mismatched unrelated donor in June 2014. The myeloablative preparative regimen consisted of cyclophosphamide at 60 mg/kg for 2 days and total body irradiation at 12 Gy. On Day 55, she was treated with prednisolone at 20 mg/day for acute GVHD (Grade III; Skin Stage 2, Gut Stage 2, Liver Stage 0) and gradually improved. She had fever, myalgia in the upper limbs, and asymptomatic sinus tachycardia on Day 145. Laboratory tests showed elevated CK, CKMB, aldolase, and troponin I. Electromyographic examination revealed myopathic abnormalities compatible with the diagnosis of myositis. Electrocardiography showed tachycardia and anteroseptal ST elevation, and echocardiography showed hypokinesia of the left interventricular septal wall without evidence of infection or leukemia relapse. She was immediately treated with 40 mg/day prednisolone after the diagnosis of polymyositis and cardiomyopathy, associated with chronic GVHD. The polymyositis and cardiomyopathy improved promptly after the administration of prednisolone and the patient remains in remission with a current maintenance program of prednisolone at 5 mg/day.

Intravascular hemolytic anemia in a patient with antibodies related to meropenem

A 76-year-old woman treated with meropenem developed intravascular hemolytic attacks. A direct antiglobulin test was positive for C3d and IgG, and drug-dependent antibody testing indicated that the antibodies were indeed drug-dependent and reacted with drug-treated RBCs and RBCs in the presence of the drug. To our knowledge, this is the first reported case in which the causative antibodies related to meropenem were identified. This case highlights the importance of maintaining a high level of suspicion for drug-induced immune hemolytic anemia in patients with explained hemolysis as well as conducting specialized serologic testing.

MUTYH, an adenine DNA glycosylase, mediates p53 tumor suppression via PARP-dependent cell death

p53-regulated caspase-independent cell death has been implicated in suppression of tumorigenesis, however, the regulating mechanisms are poorly understood. We previously reported that 8-oxoguanine (8-oxoG) accumulation in nuclear DNA (nDNA) and mitochondrial DNA triggers two distinct caspase-independent cell death through buildup of single-strand DNA breaks by MutY homolog (MUTYH), an adenine DNA glycosylase. One pathway depends on poly-ADP-ribose polymerase (PARP) and the other depends on calpains. Deficiency of MUTYH causes MUTYH-associated familial adenomatous polyposis. MUTYH thereby suppresses tumorigenesis not only by avoiding mutagenesis, but also by inducing cell death. Here, we identified the functional p53-binding site in the human MUTYH gene and demonstrated that MUTYH is transcriptionally regulated by p53, especially in the p53/DNA mismatch repair enzyme, MLH1-proficient colorectal cancer-derived HCT116+Chr3 cells. MUTYH-small interfering RNA, an inhibitor for p53 or PARP suppressed cell death without an additive effect, thus revealing that MUTYH is a potential mediator of p53 tumor suppression, which is known to be upregulated by MLH1. Moreover, we found that the p53-proficient, mismatch repair protein, MLH1-proficient colorectal cancer cell line express substantial levels of MUTYH in nuclei but not in mitochondria, suggesting that 8-oxoG accumulation in nDNA triggers MLH1/PARP-dependent cell death. These results provide new insights on the molecular mechanism of tumorigenesis and potential new strategies for cancer therapies.

Relationship between clinical factors and severity of esophageal candidiasis according to Kodsi's classification

Severe Candida esophagitis (CE) may lead to development of strictures, hemorrhage, esophagotracheal fistula, and a consequent decrease in quality of life. Although the severity of CE has been classified based on macroscopic findings on endoscopy, the clinical significance remains unknown. The aim of the study was to elucidate the predictive clinical factors for endoscopic severity of CE. Patients who underwent upper endoscopy and answered questionnaires were prospectively enrolled. Smoking, alcohol, human immunodeficiency virus (HIV) infection, diabetes mellitus, chronic renal failure, liver cirrhosis, systemic steroids use, proton pump inhibitor use, H2 blocker use, and gastrointestinal (GI) symptoms were assessed on the same day of endoscopy. GI symptoms including epigastric pain, heartburn, reflux, hunger cramps, nausea, dysphagia, and odynophagia were assessed on a 7-point Likert scale. Endoscopic severity was classified as mild (Kodsi's grade I/II) or severe (grade III/IV). Of 1855 patients, 71 (3.8%) were diagnosed with CE (mild, n = 48; severe, n = 23). In the CE patients, 50.0% (24/48) in the mild group and 23.1% (6/23) in the severe group did not have any GI symptoms. In HIV-infected patients (n = 17), a significant correlation was found between endoscopic severity and declining CD4 cell count (Spearman's rho = -0.90; P < 0.01). Multivariate analysis revealed that GI symptoms (odds ratio [OR], 3.32) and HIV infection (OR, 3.81) were independently associated with severe CE. Patients in the severe group experienced more epigastric pain (P = 0.02), reflux symptoms (P = 0.04), dysphagia (P = 0.05), and odynophagia (P < 0.01) than those in the mild group. Of the GI symptoms, odynophagia was independently associated with severe CE (OR 9.62, P = 0.02). In conclusion, the prevalence of CE in adults who underwent endoscopy was 3.8%. Silent CE was found in both mild and severe cases. Endoscopic severity was associated with characteristic GI symptoms and comorbidity of HIV infection. A decline in immune function correlated with CE disease progression.

Association of a single nucleotide polymorphism in the SH2D1A intronic region with systemic lupus erythematosus

SH2D1A, also known as signaling lymphocytic activation molecule (SLAM)-associated protein (SAP), is an adaptor protein. Recently, it was reported that SAP deficient mice were protected from systemic lupus erythematosus (SLE). In this study, we postulated SH2D1A gene to be a candidate susceptibility gene for SLE and analyzed its association with SLE. A case-control association study was conducted on 5 tag single nucleotide polymorphisms (SNPs) in SH2D1A region in 506 Japanese female SLE patients and 330 healthy female controls. The luciferase assay was performed to determine the functional role of the SNP associated with SLE. One SNP in the intron 2, rs2049995, showed association with SLE (p=0.0110, odds ratio (OR) 1.97, 95% confidence interval (CI) 1.16-3.34, under the dominant model). The association of rs2049995 seemed to be stronger in the subset with the age of onset less than 20 years (p=0.0067, OR 2.65, 95% CI 1.28-5.46). Functional evaluation of rs2049995 showed that reporter gene activity was increased 1.9-fold for the susceptible allele compared with the resistant allele. An intronic SNP of SH2D1A is associated with SLE.

Small bowel metastasis of hepatocellular carcinoma detected by capsule endoscopy

We report a rare case of metastasis of hepatocellular carcinoma (HCC) to the small bowel that presented as a pedunculated epithelial polyp. A 60-year-old man with liver cirrhosis type B was treated for HCC (stage IVb) at our hospital. He had been admitted for melena and anemia. Capsule endoscopy was performed in this patient with obscure gastrointestinal bleeding. It showed a polypoid lesion with bleeding in the ileum. Double-balloon endoscopy was performed. The lesion was determined to be a pedunculated polyp in the ileum. Histological examination of biopsy specimens showed tumor cells resembling HCC. We performed endoscopic mucosal resection for the lesion by double-balloon endoscopy to prevent bleeding from the tumor. The patient had no melena or anemia and his condition improved after endoscopic mucosal resection. However, he died of liver failure 2 months later.

Raltegravir can be used safely in HIV-1-infected patients treated with warfarin

Drug co-administration often affects the patient response to warfarin through various mechanisms. We describe here five HIV-1-infected patients on treatment with warfarin in whom the use of raltegravir was associated with a favourable outcome.

Flow cytometric analysis of kappa and lambda light chain expression in endoscopic biopsy specimens before the diagnosis of B-cell lymphoma

Forty-eight patients with gastrointestinal (GI) tract B-cell lymphoma (BCL) were analyzed retrospectively. The diagnosis was based on the histological examination of specimens obtained by endoscopic biopsy. Before the diagnosis was made, single-color flow cytometry was performed to analyze the expression of light chains and B-cell antigens including CD10 in the specimens. Restricted light chain (RLC) expression, a marker of B-cell clonality, was defined as κ and λ ratios of either more than 3.0 or less than 0.5. The specimens from 30 patients (62.5%) showed RLC expression. No RLC expression or RLC expression not examined was divided into two groups : those showing CD10 positivity in more than 20% of cells (4 patients, 8.3%) and those showing no positivity (14 patients, 29.2%). The cell number analyzed in the latter group was significantly smaller than that in the other two groups. Abnormal karyotypes were found in the specimens from 8 patients (16.7%). These results indicate that the flow cytometric analysis of endoscopic biopsy specimens is useful when BCL is suspected if an adequate number of cells are obtained.

[Development of donor cell leukemia mimicking hematogones after unrelated cord blood transplantation for relapsed acute lymphoblastic leukemia]

A 26-year-old woman, who developed ALL when she was eighteen years old, achieved remission after chemotherapy. Her ALL relapsed when she was twenty-two years old. After re-induction therapy, she underwent cord blood transplantation. Her bone marrow examination on the 42nd day revealed a lymphoblast count of 16%. She was observed without any therapy, but her bone marrow blast count continued to be around 6% for three years without any symptoms. The bone marrow blast fraction originated from the cord blood. Surface marker analysis of the blast fraction initially revealed a pattern of hematogones that was CD10 and CD19 positive, but then showed a myeloblast pattern that was CD13 and CD33 positive. AML developed as donor cell leukemia. When blasts appear in the early phase after transplantation and persist, an observation period is necessary with molecular chimerism, morphology, and surface marker analysis of the blast fraction to consider relapse, hematogones, or donor cell leukemia.

Restriction fragment mass polymorphism (RFMP) analysis based on MALDI-TOF mass spectrometry for detecting antiretroviral resistance in HIV-1 infected patients

Viral genotype assessment is important for effective clinical management of HIV-1 infected patients, especially when access and/or adherence to antiretroviral treatment is reduced. In this study, we describe development of a matrix-assisted laser desorption/ionization-time of flight mass spectrometry-based viral genotyping assay, termed restriction fragment mass polymorphism (RFMP). This assay is suitable for sensitive, specific and high-throughput detection of multiple drug-resistant HIV-1 variants. One hundred serum samples from 60 HIV-1-infected patients previously exposed to nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs) were analysed for the presence of drug-resistant viruses using the RFMP and direct sequencing assays. Probit analysis predicted a detection limit of 223.02 copies/mL for the RFMP assay and 1268.11 copies/mL for the direct sequencing assays using HIV-1 RNA Positive Quality Control Series. The concordance rates between the RFMP and direct sequencing assays for the examined codons were 97% (K65R), 97% (T69Ins/D), 97% (L74VI), 97% (K103N), 96% (V106AM), 97% (Q151M), 97% (Y181C), 97% (M184VI) and 94% (T215YF) in the reverse transcriptase coding region, and 100% (D30N), 100% (M46I), 100% (G48V), 100% (I50V), 100% (I54LS), 99% (V82A), 99% (I84V) and 100% (L90M) in the protease coding region. Defined mixtures were consistently and accurately identified by RFMP at 5% relative concentration of mutant to wild-type virus while at 20% or greater by direct sequencing. The RFMP assay based on mass spectrometry proved to be sensitive, accurate and reliable for monitoring the emergence and early detection of HIV-1 genotypic variants that lead to drug resistance.

Predictors of clinical progression in HIV-1-infected adults initiating combination antiretroviral therapy with advanced disease in the Asia-Pacific region: results from the TREAT Asia HIV observational database

The majority of HIV-infected patients in developing countries commences combination antiretroviral therapy (cART) with advanced disease. We examined predictors of disease progression in patients initiating cART with CD4 count ≤200 cells/mm(3) in the TREAT Asia HIV Observational Database. The main outcome measure was progression to either an AIDS-defining illness or death occurring 6 months after initiation of cART. We used survival analysis methods. A total of 1255 patients contributed 2696 person years of follow-up; 73 were diagnosed with AIDS and 9 died. The rate of progression to the combined end point was 3.0 per 100 person years. The factors significantly associated with a higher risk of disease progression were Indian ethnicity, infection through intravenous drug use, lower CD4 count, and hemoglobin ≤130 g/dL at 6 months. In conclusion, measurements of CD4 count and hemoglobin at month 6 may be useful for early identification of disease progression in resource-limited settings.

Prediction of progression from refractory cytopenia with unilineage dysplasia by analysis of bone marrow blast cell composition

A retrospective analysis of 71 patients newly diagnosed with refractory cytopenia with unilineage dysplasia (RCUD) revealed that 12 developed refractory anemia with an excess of blasts or acute myeloblastic leukemia. Before the diagnosis of RCUD was made, phenotypes of cells in the bone marrow (BM) blast region were analyzed using flow cytometry. Patients with RCUD were divided into two groups ; those with no progression (Group A) and those with disease progression later on (Group B). The cell composition in the BM blast region differed significantly between the groups : Group A showed higher percentages of B lymphoid cells but lower percentages of myeloid cells. A cut-off value of 20 for the CD33/CD10 ratio in the BM blast region clearly separated Group A from Group B. These results suggest that cell composition in the BM blast region evaluated by flow cytometry may indicate the progression of RCUD.

A double-blind comparative study of the safety and efficacy of caspofungin versus micafungin in the treatment of candidiasis and aspergillosis

The safety and efficacy profile of caspofungin and micafungin in Japanese patients with fungal infections were directly compared in this prospective, randomized, double-blind study. The proportion of patients who developed significant drug-related adverse event(s) (defined as a serious drug-related adverse event or a drug-related adverse event leading to study therapy discontinuation) was compared in 120 patients [caspofungin 50 mg, or 50 mg following a 70-mg loading dose on Day 1 (hereinafter, 70/50 mg) group: 60 patients; micafungin 150 mg: 60 patients]. The overall response rate was primarily evaluated in the per-protocol set (PPS) population. The proportion of patients who developed significant drug-related adverse events was 5.0 % (3/60) in the caspofungin group and 10.0 % (6/60) in the micafungin group [95 % confidence interval (CI) for the difference: -15.9 %, 5.2 %]. The favorable overall response in the PPS population for patients with esophageal candidiasis, invasive candidiasis, and chronic pulmonary aspergillosis including aspergilloma was 100.0 % (6/6), 100.0 % (3/3), and 46.7 % (14/30) in the caspofungin group, and 83.3 % (5/6), 100.0 % (1/1), and 42.4 % (14/33) in the micafungin group, respectively. In Japanese patients with Candida or Aspergillus infections, there was no statistical difference in the safety between caspofungin and micafungin. Consistent with other data on these two agents, the efficacy of caspofungin and micafungin was similar.

The relationship between HIV testing and CD4 counts at HIV diagnosis among newly diagnosed HIV-1 patients in Japan

The aim of this study was to investigate the factors relating to CD4 level at HIV diagnosis and HIV testing behaviour. Participants were newly diagnosed patients (n = 654) in Japan from 2000 to 2005. Around 75% of participants were diagnosed at hospital and clinics. Mean CD4 counts at diagnosis through voluntary HIV testing, screening tests and testing due to concomitant sexually transmitted infection (STI) were 368, 336 and 316 cells/μL, respectively. In contrast, the mean CD4 count where testing was due to the presence of HIV-related clinical symptoms was 151 cells/μL (P < 0.0001). Compared with those diagnosed at their first HIV test, those who had undertaken multiple HIV tests prior to diagnosis showed CD4 counts that increased significantly (P < 0.0001) in relation to the number of tests undertaken: CD4 count at first test was 232 cells/μL, second test 346 cells/μL and third or additional tests 439 cells/μL. According to our results, HIV testing policy that promotes HIV testing in medical settings and among STI patients is needed to facilitate earlier HIV diagnosis in Japan.

Identification of a novel HLA allele, HLA-DQB1*06:51, in a Japanese rheumatoid arthritis patient

A novel HLA allele, HLA-DQB1*06:51, was identified in a Japanese rheumatoid arthritis patient.

Predictive value of endoscopic findings in the diagnosis of active intestinal amebiasis

Endoscopic diagnosis of amebic colitis can be difficult because its appearance may mimic other forms of colonic disease. The aim of this study was to identify predictive endoscopic findings for amebic colitis. Patients with suspected amebic colitis based on distinctive endoscopic findings such as aphthae or erosions, ulcers, exudates, or a bump, were included in the study. A total of 157 patients were selected, 50 of whom had amebic colitis. The sensitivity and specificity of endoscopic findings that were significantly associated with amebic colitis were: cecal lesions (80% and 54%), multiple number of lesions (96% and 29%), presence of aphthae or erosions (84% and 37%), and presence of exudate (88% and 74%). Multivariate analysis revealed that the best combination of findings to predict amebic colitis was the presence of cecal lesions, multiple lesions, and exudates, which corresponded to an area under the receiver operating characteristic curve of 0.89 (95% confidence interval 0.82-0.95).

Regression of rectal MALT lymphoma after antibiotic treatment in a patient negative for Helicobacter pylori

A 53-year-old man was referred to our hospital with bloody stool. Barium enema study and colonoscopy revealed multiple small nodules on the anterior wall of the lower rectum. Biopsy specimens showed proliferation of atypical lymphoid cells forming the nodules. Mucosa-associated lymphoid tissue lymphoma was diagnosed on the basis of histologic and immunohistochemical examinations. No metastasis was detected in lymph nodes or distant organs, indicative of clinical stage I disease. Although the test results were negative for Helicobacter pylori, eradication therapy was performed. The lesion disappeared completely within 9 months after the triple antibiotic therapy. H. pylori eradication therapy may be a useful treatment option regardless of H. pylori status.

Prognostic significance of lymphovascular invasion for patients with stage I non-small cell lung cancer

AIMS

This study retrospectively investigated the clinical significance of lymphovascular invasion (LVI) following a complete resection for stage I non-small cell lung cancer (NSCLC).

METHODS

A total of 226 patients who underwent a complete resection for pathological stage I NSCLC were examined.

RESULTS

Lymphatic invasion was pathologically diagnosed as ly0 in 156 patients, ly1 in 65, and ly2 in 5 patients. The pathological vascular invasion was diagnosed as v0 in 178 patients, v1 in 35, v2 in 10, and v3 in 3 patients. The 5-year survival rate after surgery of the patients with and without lymphatic invasion was 76.8 and 90.6%, respectively. There was a significantly more unfavorable prognosis in patients with lymphatic invasion (p = 0.042). The 5-year survival rate of the patients with vascular invasion was also significantly more unfavorable (67.8%) than that of patients without vascular invasion (90.4%; p = 0.004). LVI was found to significantly correlate with tumor size and the presence of pleural invasion.

CONCLUSION

The LVI of NSCLC is a significant prognostic factor in patients with stage I tumors. In future clinical trials, it is necessary to evaluate the efficacy of adjuvant therapy for the selection of patients according to this criterion.

Results of a Surgical Resection for Patients with Thymic Carcinoma

Objectives:

This study investigated the clinical features of patients with complete resection of thymic carcinoma.

Patients and Methods:

The clinical records from 11 patients who underwent a complete resection of thymic carcinoma were retrospectively reviewed.

Results:

Twelve of 22 patients underwent a resection (a complete resection in 11 and an incomplete in 1). Six of the 11 patients with complete had confirmed recurrent tumors. The 5-year survival rate was 45.4%, and the median survival time was 50.6 months. The patients who underwent complete resection showed significantly better prognosis than cases with incomplete resection and inoperable cases ( p = 0.048). Three of the 6 patients had a recurrence within 1 year. Frequent sites of recurrence were the pleura, pericardium, and lung.

Conclusions:

A complete resection improved the prognosis of thymic carcinoma. Further prospective studies regarding postoperative adjuvant therapy are necessary to prevent local recurrence after a surgical resection for thymic carcinoma.

A Study of Surgically Resected Peripheral Non-Small Cell Lung Cancer with a Tumor Diameter of 1.0 CM or Less

Background and Aims:

The widespread use of high resolution computed tomography has increased the number of small peripheral lung cancers. This study reviewed the clinicopathological features of the patients with non-small cell lung cancer (NSCLC) with a tumor diameter of 1 cm or less, in order to explore the adequate management of such small sized lung cancers.

Material and Methods:

This study was a retrospective analysis of consecutive 58 patients (5.3% out of 1095 patients) who underwent a complete resection for a peripheral NSCLC with a diameter of 1.0 cm or less. The clinical features and outcomes were compared with 203 patients with NSCLC with a diameter between 1.1 and 2.0 cm.

Results:

The mean age was 64.5 years and there were 26 males and 32 females. Clinical stage was IA in 57 (98%) and IIIA in 1. Lobectomy was performed in 39 patients, segmentectomy in nine, and nonanatomic wedge resection in ten. Two patients, who underwent systemic lymph node dissection, had mediastinal lymph node metastasis and were diagnosed as pathological stage IIIA; however they did not relapse after surgery. One patient with pathological stage IA papillary adenocarcinoma died due to brain metastases. The five-year overall survival rate and disease free survival rate was 95.0% and 95.3%, respectively. Patients with NSCLC of 1.0 cm or less showed significantly better survival than those with tumors measuring 1.1–2.0 cm in size (p = 0.048).

Discussion:

The indications for avoiding systemic lymph node dissection for operable NSCLC should not be based on the size of the tumor. A small-sized lung cancer might be surgically treated before the tumor enlarges to more than 1.0 cm in size.