Feasibility and clinical utility of comprehensive genomic profiling of hematological malignancies.

Identification of genetic alterations through next-generation sequencing (NGS) can guide treatment decision-making by providing information on diagnosis, therapy selection, and prognostic stratification in patients with hematological malignancies. Although the utility of NGS-based genomic profiling assays was investigated in hematological malignancies, no assays sufficiently cover driver mutations, including recently discovered ones, as well as fusions and/or pathogenic germline variants. To address these issues, here we have devised an integrated DNA/RNA profiling assay to detect various types of somatic alterations and germline variants at once. Particularly, our assay can successfully identify copy number alterations and structural variations, including immunoglobulin heavy chain translocations, IKZF1 intragenic deletions, and rare fusions. Using this assay, we conducted a prospective study to investigate the feasibility and clinical usefulness of comprehensive genomic profiling for 452 recurrently altered genes in hematological malignancies. In total, 176 patients (with 188 specimens) were analyzed, in which at least one alteration was detected in 171 (97%) patients, with a median number of total alterations of 7 (0-55). Among them, 145 (82%), 86 (49%), and 102 (58%) patients harbored at least one clinically relevant alteration for diagnosis, treatment, and prognosis, respectively. The proportion of patients with clinically relevant alterations was the highest in acute myeloid leukemia, whereas this assay was less informative in T/natural killer-cell lymphoma. These results suggest the clinical utility of NGS-based genomic profiling, particularly for their diagnosis and prognostic prediction, thereby highlighting the promise of precision medicine in hematological malignancies.

Improvement of urinary symptoms after bladder biopsy: A case of pathologically proven allergy-related cystitis during administration of nivolumab.

INTRODUCTION: We present a case of cystitis, which was considered to be an immune-related adverse event associated with nivolumab administration. CASE PRESENTATION: A 47-year-old man suffered from sudden onset urinary symptoms after 18 cycles of nivolumab treatment for stage IV pulmonary adenocarcinoma. Urine culture and urine cytology were both negative. The symptoms were inferred to be related to nivolumab administration, and a bladder biopsy under spinal anesthesia was performed. The histopathological examination showed the evidence of allergic-related cystitis. We planned to administer corticosteroids, but the urinary symptoms disappeared after the bladder biopsy. Nivolumab treatment was continued without recurrent bladder symptoms. CONCLUSION: We reported a case of cystitis after treatment with nivolumab, which served as a reminder to consider the possibility of immune-related adverse events as a potential cause for any symptoms that develop during treatment with immuno-oncology drugs.

Correlation between the number of viable tumor cells and immune cells in the tumor microenvironment in non-small cell lung cancer after induction therapy.

This study aims to determine the correlation between the percent viable tumor cells (%VTC) and the tumor microenvironment in resected non-small cell lung cancer after induction therapy. We enrolled 72 patients with non-small cell lung cancer (NSCLC) who received chemoradiotherapy (CRT) or chemotherapy (CT) prior to surgery. The ratio of the area of viable tumor cells to the total tumor area was calculated to obtain the %VTC. We also examined the number of CD4 (+), CD8 (+), CD20 (+) and FOXP3 (+) tumor-infiltrating lymphocytes (TILs), podoplanin (PDPN) (+) cancer-associated fibroblasts (CAFs), and CD204 (+) tumor-associated macrophages (TAMs) by immunohistochemistry (IHC). In the CRT group (n = 37), the tumors had significantly lower %VTC than the CT group (n = 35) (P < 0.001). In both of the CT group and CRT group, the %VTC showed a significant positive correlation with the number of CD204 (+)-TAMs (P = 0.014 and 0.005, respectively). Only in the CRT group, a higher number of CD204 (+) TAMs was associated with a shorter overall survival (OS) (P = 0.007) and recurrence-free survival (RFS) (P = 0.015). In the CRT group, the number of CD204 (+) TAMs is associated with %VTC and prognosis, suggesting that these cells may have tumor-promoting effects on the residual lung cancer in specific microenvironments after CRT.

Brentuximab vedotin maintenance after autologous stem cell transplantation for refractory gray zone lymphoma with long-term remission.

Gray zone lymphoma (GZL) is a rare type of B-cell lymphoma characterized by features of both diffuse large B-cell lymphoma and classical Hodgkin lymphoma (cHL). The prognosis of GZL is poorer than that of cHL and mediastinal large B-cell lymphoma. However, an optimal treatment strategy for relapsed/refractory (R/R) GZL has not been established in the clinical setting. The current study reported an excellent clinical response in a patient with R/R CD30-positive GZL who received brentuximab vedotin (BV) maintenance after autologous stem cell transplantation (ASCT). Although the patient was resistant to prior treatments, BV maintenance after ASCT achieved long-term remission. Hence, BV was determined to be a safe and effective therapeutic option for CD30-positive R/R GZL.

Evaluation of the morphological features and unfavorable prognostic impact of dirty necrosis in renal cell carcinoma.

PURPOSE: Tumor necrosis (TN) is one of the unfavorable prognostic factors in renal cell carcinoma (RCC). We identified two patterns of TN according to their morphology: dirty necrosis and ghost necrosis. We aimed to elucidate the morphological features and unfavorable prognostic impact of dirty necrosis in RCC. METHODS: A total of 261 tumors collected after nephrectomy, which were pathologically identified as RCC, were analyzed in this study. We classified TN as dirty necrosis or ghost necrosis and compared their clinicopathological features. We also assessed their morphological features using digitally analyzed slides. The correlation between tumor size and necrosis area or the number of necrotic foci was calculated. RESULTS: There were 77 tumors (30%) with TN, and the presence of TN was significantly associated with unfavorable clinicopathological factors. Thirty tumors (39%) had dirty necrosis, and 47 tumors (61%) had ghost necrosis. There were significantly higher numbers of unfavorable factors associated with dirty necrosis than with ghost necrosis. In dirty necrosis, both the TN area and the number of necrotic foci were correlated with tumor size (p < 0.001 and p = 0.003, respectively). However, in ghost necrosis, no correlation was found between tumor size and the number of necrotic foci (p = 0.58). Tumors (without stage IV) with dirty necrosis had a significantly shorter disease-free survival time than those with ghost necrosis and those without TN (p = 0.024 and p < 0.001, respectively). CONCLUSION: Dirty necrosis has potential as an unfavorable prognostic indicator of surgically resected RCC.

Prognostic impact of the tumor immune microenvironment in pulmonary pleomorphic carcinoma.

INTRODUCTION: Pulmonary pleomorphic carcinoma (PC) is a rare non-small cell lung carcinoma (NSCLC) and is characterized by sarcomatoid and NSCLC components. This study aimed to characterize the association between immune microenvironmental factors and clinicopathological characteristics of PC. METHODS: Eighty consecutive PC patients who had undergone complete surgical resection were enrolled. We calculated the immunohistochemical staining scores for E-cadherin, vimentin, programmed death ligand 1 (PD-L1), and carbonic anhydrase IX in cancer cells and counted the numbers of CD204-positive tumor-associated macrophages (TAMs) and Foxp3-, CD8-, and CD20-positive tumor-infiltrating lymphocytes (TILs). We also examined the association between these scores and the prognostic outcomes. RESULTS: The staining score for PD-L1 in cancer cells and the number of CD204-positive TAMs in the sarcomatoid component were significantly higher than those in the NSCLC component; E-cadherin score in the sarcomatoid component was significantly lower. Patients with high PD-L1 expression in the NSCLC component had significantly longer overall survival (OS) and recurrence-free survival (RFS) than those with low PD-L1 expression in the NSCLC component (OS: p = 0.001, RFS: p = 0.038). Multivariate analysis revealed that high PD-L1 expression in the NSCLC component was an independent favorable prognostic factor for OS (p = 0.018), whereas high PD-L1 expression in the sarcomatoid component was not. The number of CD8-positive TILs was significantly higher in the high PD-L1 expression group than in the low expression group (NSCLC components: p < 0.001). CONCLUSION: High PD-L1 expression in the NSCLC component may be associated with a favorable prognostic value in pulmonary PC.

Relationship between podoplanin-expressing cancer-associated fibroblasts and the immune microenvironment of early lung squamous cell carcinoma.

AIM: Cancer-associated fibroblasts (CAFs) expressing podoplanin (PDPN) harbor a fibrous tumor microenvironment that promotes cancer progression in lung adenocarcinoma. In this study, we investigated whether tumor-promoting PDPN+ CAFs contribute to the immunosuppressive microenvironment in lung squamous cell carcinoma (SqCC). M&M: The gene expression profiles of immunosuppressive cytokines were compared using The Cancer Genome Atlas (TCGA) microarray lung SqCC data (n = 484) between a PDPN-high group and a PDPN-low group. Further, using patient-derived CAFs from surgically resected lung SqCC, the PDPN+ fraction was sorted and gene and protein expressions were analyzed. Finally, immunohistochemical staining was conducted on 131 surgically resected lung SqCC; CD8+ and FOXP3+ tumor infiltrating lymphocytes (TILs), and CD204+ tumor-associated macrophages (TAMs) were evaluated in cases with PDPN+ and PDPN- CAFs. RESULTS: Analysis of TCGA database revealed that the PDPN-high group exhibited significantly higher expression of interleukin (IL)-1A, IL-1B, IL-6, IL-10, monocyte chemoattractant protein-1 (CCL2), colony stimulating factor 1 (CSF1), fibroblast growth factor 2 (FGF2), galectin 1 (LGALS1), platelet derived growth factor subunit A (PDGFA), PDGFB, and transforming growth factor-ß1 (TGFB1) than those in the PDPN-low group. Among them, it was found that TGFB1 expression was higher in patient-derived PDPN+ CAFs. Immunohistochemical analyses revealed that more CD204+ TAMs infiltrated the tumor tissues in cases with PDPN+ CAFs than in cases with PDPN- CAFs (P <  0.03), while CD8+ and FOXP3+ TILs did not. Furthermore, in the same tumor, CD204+ TAMs infiltrated more in PDPN+ CAF-rich areas (P =  0.005). CONCLUSION: PDPN+ CAFs showed higher expression of TGFB1 and were associated with CD204+ TAM infiltration in stage-I lung SqCC, suggesting that PDPN+ CAFs were associated with the immunosuppressive tumor microenvironment.

Transformation Scoring System (TSS): A new assessment index for clinical transformation of follicular lymphoma.

Although histologic analysis is the gold standard for diagnosing follicular lymphoma (FL) transformation, many patients are diagnosed with transformation by clinical factors as biopsy specimens often cannot be obtained. Despite the frequency of clinical diagnosis, no clinical assessment tool has yet been established for FL transformation in the rituximab era. We derived and validated a transformation scoring system (TSS) based on retrospective analyses of 126 patients with biopsy-proven FL and histologic transformation (HT) at two hospitals of the National Cancer Center of Japan. In the derivation set (76 patients), the detailed analyses of the clinical characteristics at disease progression showed that lactate dehydrogenase (LDH) elevation, focal lymph nodal (LN) enlargement, hemoglobin <12 g/dl, and poor performance status (PS) (2-4) were associated with HT. The weights of these variables were decided based on the regression coefficients. Next, we constructed a TSS encompassing the above four factors: LDH, (> upper limit of normal [ULN], ≤ULN ×2) (1 point), (≥ULN ×2) (2 points); focal LN enlargement, (≥3 cm, <7 cm) (1 point), (≥7 cm) (2 points); hemoglobin <12 g/dl (1 point); poor PS (2 points). We identified a high positive predictive value (PPV) (96.4%) and negative predictive value (NPV) (85.4%) for diagnosing HT when a cutoff score of 2 was selected for our TSS. In an external validation set (50 patients), the probability of HT was high with scores ≥2 (PPV, 93.3%; NPV, 82.9%). We developed a TSS that offers a simple, yet, valuable tool, for diagnosing HT, especially in patients who cannot undergo biopsy.

The critical role of CD4+ T cells in PD-1 blockade against MHC-II-expressing tumors such as classic Hodgkin lymphoma.

Classic Hodgkin lymphoma (cHL) responds markedly to PD-1 blockade therapy, and the clinical responses are reportedly dependent on expression of major histocompatibility complex class II (MHC-II). This dependence is different from other solid tumors, in which the MHC class I (MHC-I)/CD8+ T-cell axis plays a critical role. In this study, we investigated the role of the MHC-II/CD4+ T-cell axis in the antitumor effect of PD-1 blockade on cHL. In cHL, MHC-I expression was frequently lost, but MHC-II expression was maintained. CD4+ T cells highly infiltrated the tumor microenvironment of MHC-II-expressing cHL, regardless of MHC-I expression status. Consequently, CD4+ T-cell, but not CD8+ T-cell, infiltration was a good prognostic factor in cHL, and PD-1 blockade showed antitumor efficacy against MHC-II-expressing cHL associated with CD4+ T-cell infiltration. Murine lymphoma and solid tumor models revealed the critical role of antitumor effects mediated by CD4+ T cells: an anti-PD-1 monoclonal antibody exerted antitumor effects on MHC-I-MHC-II+ tumors but not on MHC-I-MHC-II- tumors, in a cytotoxic CD4+ T-cell-dependent manner. Furthermore, LAG-3, which reportedly binds to MHC-II, was highly expressed by tumor-infiltrating CD4+ T cells in MHC-II-expressing tumors. Therefore, the combination of LAG-3 blockade with PD-1 blockade showed a far stronger antitumor immunity compared with either treatment alone. We propose that PD-1 blockade therapies have antitumor effects on MHC-II-expressing tumors such as cHL that are mediated by cytotoxic CD4+ T cells and that LAG-3 could be a candidate for combination therapy with PD-1 blockade.

Machine learning-based histological classification that predicts recurrence of peripheral lung squamous cell carcinoma.

BACKGROUND: Cancer tissue is composed of both a cancer cell component and a stromal component. The aim of this study was to investigate if the component ratio predicts a prognosis for lung squamous cell carcinoma (SqCC) patients by using a machine learning method. METHODS: A total of 135 peripheral SqCC cases (tumor size: 3-5 cm) were enrolled in this study. The areas of the cancer cell component, the necrotic component, and the stromal component were accurately measured via a machine learning method. Each case was divided into the following three subtypes: 1) predominant cancer cell, 2) predominant necrosis, and 3) predominant stroma. The study examined if a particular subtype had prognostic significance. RESULTS: The number of cases per subtype of predominant cancer cell, predominant necrosis, and predominant stroma was 59, 6, and 70, respectively. Patients with the predominant stroma subtype had a significantly shorter recurrence free survival (RFS) than did those with the predominant cancer cell subtype (5-yr RFS: 42.3 % vs. 84.3 %,p < 0.01). Also, in pathological stage I patients, the 5-year RFS rate for the predominant stroma subtype was significantly shorter (5-yr RFS: 64.3 % vs. 88.4 %, p < 0.01). In the multivariate analysis of p-stage I patients, the predominant stroma subtype was confirmed to be an independent prognostic factor for RFS (p < 0.01). CONCLUSION: Using machine learning, the study confirmed that the predominant stroma subtype was an independent factor for RFS, suggesting that the ratio of the stromal component correlates with the malignant potential of SqCC.

Association between the mutational smoking signature and the immune microenvironment in lung adenocarcinoma.

OBJECTIVES: Mutational signatures associated with tobacco smoking (mutational smoking signatures: SS) are characterized mainly by C > A mutations. The aim of this study was to characterize the association between the tumor immune microenvironment and the SS in lung adenocarcinoma. METHODS: Lung adenocarcinomas surgically resected from 96 patients, for which whole exome sequencing data was available, were included in the study. We extracted the SS from whole exome sequencing data, calculated the weights of SS using deconstructSigs, and compared the clinicopathological features of SS positive (SS+) and negative (SS-) adenocarcinomas. We selected 18 tumor pairs from SS + and SS- adenocarcinomas (sex, EGFR mutation, and tumor size-matched) and examined the expression of five immune markers (CD20, CD8, FOXP3, CD204, and PD-L1) by immunohistochemistry. RESULTS: Of 96 specimens, there were 33 (34 %) SS + adenocarcinoma tumors. The smoking index significantly correlated with the weight of the SS (R = 0.43). Between SS + and SS- tumors, there was no significant difference in clinicopathological factors excluding smoking history. Immunohistochemistry revealed that the number of FOXP3 + T cells in SS + adenocarcinomas was significantly higher than that in the SS- adenocarcinomas (median number 58 vs. 36, p < 0.01). Also, the number of CD20 + B cells in SS + adenocarcinomas was significantly higher than that in the SS- adenocarcinomas (median number 77 vs. 29, p < 0.01); however; these phenomena could not be confirmed when stratified by smoking history. CONCLUSION: In lung adenocarcinoma, SS is associated with an immunosuppressive tumor microenvironment.

Fibroblasts-dependent invasion of podoplanin-positive cancer stem cells in squamous cell carcinoma.

To clear whether podoplanin-positive cancer stem cells in squamous cell carcinoma have higher invasion activity during a fibroblasts-dependent invasion. A collagen gel invasion assay was performed using fluorescent ubiquitination-based cell cycle indicator-labeled A431 cells. The total number and number of invading cells in S/G2/M phase were counted using time-lapse imaging cocultured with fibroblasts. There was no significant difference between the number of invading podoplanin-positive and negative A431 cells when fibroblasts did not exist. On the contrary, the number of invading podoplanin-positive cells was significantly higher when fibroblasts existed. The frequency of cells in S/G2/M phase among invasion was no difference. Knockdown of podoplanin decreased the number of invaded A431 cells significantly when fibroblasts existed. Podoplanin-positive A431 cells display higher invasion activity when fibroblasts exist, suggesting that some biological functions of cancer stem cells might become evident only within the fibrous tumor microenvironment.

Proportion of goblet cell is associated with malignant potential in invasive mucinous adenocarcinoma of the lung.

Invasive mucinous adenocarcinoma (IMA) is a newly classified variant of lung adenocarcinoma. The aim of this study was to examine the correlation between the proportion of goblet cells and the clinicopathological characteristics of IMA. Ninety-nine patients with stage I IMA were included in this study. We estimated prognostic impact of goblet cell proportion. We classified them into two groups: the cases with a high goblet cell proportion (HGP, goblet cell proportion ≥80%) and the cases with a low goblet cell proportion (LGP, goblet cell proportion ≤30%), and compared the expression levels of five cancer progression markers and the number of tumor-promoting stromal cells between the two groups. Univariate and multivariate analysis revealed that the goblet cell proportion was a prognostic factor for recurrence free survival (P < 0.01) and overall survival (P = 0.01). The expression levels of the cancer stem cell-related marker, ALDH-1, and proliferation-related marker, geminin were significantly higher in the LGP group than in the HGP group. CD204+ tumor-associated macrophages were significantly more in the LGP stroma than the HGP stroma. Our current study indicated that the proportion of goblet cells was correlated with the malignant potential in surgically resected IMA.

A case of invasive mucinous adenocarcinoma of the lung showing stepwise progression at the primary site.

OBJECTIVE: Invasive mucinous adenocarcinoma (IMA) is a variant of lung adenocarcinoma. We present one case of IMA with mixed mucinous and non-mucinous components, suggesting stepwise progression within the tumor. MATERIAL AND METHOD: The two different components of IMA were separately examined by immunohistochemistry and performed amplicon sequencing (Ion Ampliseq Cancer Hotspot Panel v2, ilumina, San Diego, CA). RESULT: Macroscopically, the IMA contained a small and well demarcated solid part. Tumor cells in the main part showed abundant intracytoplasmic mucin, whereas those in the solid part showed scant intracytoplasmic mucin and high-grade nuclear atypia. Both parts harbored the same KRAS p.G12 V mutation. The amplicon sequencing of the IMA showed oncogenic TP53 p.P278 L mutation was detected only in the solid part. CONCLUSION: Oncogenetic TP53 mutation might promote stepwise progression of this case of IMA.

Interaction between cancer cells and cancer-associated fibroblasts after cisplatin treatment promotes cancer cell regrowth.

Regrowth of cancer cells following chemotherapy is a significant problem for cancer patients. This study examined whether cancer-associated fibroblasts (CAFs), a major component of a tumor microenvironment, promote cancer cell regrowth after chemotherapy. First, we treated human lung adenocarcinoma cell line A549 and CAFs from four patients with cisplatin. Cisplatin treatment inhibited the viable cell number of A549 cells and induced epithelial-mesenchymal transition. After cisplatin was removed, A549 cells continued to manifest the mesenchymal phenotype and proliferated 2.2-fold in 4 days (regrowth of A549 cells). Cisplatin treatment inhibited the viable cell number of CAFs from four patients also. The CM (derived from cisplatin-pretreated CAFs from two patients) significantly enhanced the regrowth of cisplatin-pretreated A549 cells, and the CM derived from cisplatin-naïve CAFs marginally enhanced A549 regrowth. By contrast, the CM derived from either cisplatin-pretreated CAFs or cisplatin-naïve CAFs failed to enhance the growth of cisplatin-naïve A549 cells. The CM derived from cisplatin-pretreated CAFs did not enhance the proliferation of A549 cells in which epithelial-mesenchymal transition was induced by TGFß-1. Our findings indicate the possibility that humoral factors from cisplatin-pretreated CAFs promote the regrowth of cisplatin-pretreated A549 cells. These results suggest that interactions between cancer cells and CAFs may significantly enhance cancer cell regrowth within the tumor microenvironment after cisplatin treatment.

Organoid culture containing cancer cells and stromal cells reveals that podoplanin-positive cancer-associated fibroblasts enhance proliferation of lung cancer cells.

OBJECTIVE: Podoplanin-positive cancer-associated fibroblasts (CAFs) play an important role in tumor progression. The aim of this study was to evaluate the effect of podoplanin (+) CAFs on the proliferation of cancer cells using a three-dimensional (3D) organoid model. MATERIALS AND METHODS: We examined the success rate of organoid culture containing PC-9 cancer cells and CAFs. Thereafter, we compared the proliferating index (MIB-1 index) of PC-9 cells co-cultured with podoplanin-overexpressing CAFs and control CAFs using organoid specimens. Furthermore, we compared the MIB-1 labeling index of cancer cells in podoplanin (+) CAFs cases (n = 13) and podoplanin (-) CAFs cases (n = 14) using surgically resected adenocarcinoma specimens. RESULTS: Without CAFs, PC-9 cells did not form any organoid (success rate: 0%). When PC-9 cells were mixed with CAFs (1:10), the mixed cells generated round and steric aggregates (hybrid cancer organoids, success rate: 100%). In three independent experiments, the MIB-1 index of PC-9 cells in hybrid cancer organoids containing podoplanin-overexpressing CAFs was significantly higher than that of PC-9 cells in organoids containing control CAFs (Exp. 1: 40.4% vs. 24.4%; Exp. 2: 40.0% vs. 24.5%; Exp. 3: 40.3% vs. 25.2%; p < 0.001). Surgically resected human tumors revealed that the MIB-1 index of adenocarcinoma cells was significantly higher in the case of podoplanin (+) CAFs than in the case of podoplanin (-) CAFs (34.8% vs. 16.2%; p < 0.01). CONCLUSION: Our data suggested that the hybrid cancer organoid model might reflect the growth-promoting effect of podoplanin (+) CAFs in cancer cells, and this new system can be a useful tool for evaluating the tumor microenvironment.

Extra-perigastric Extranodal Metastasis is a Significant Prognostic Factor in Node-Positive Gastric Cancer.

BACKGROUND: Extranodal metastasis is an isolated tumor nodule without a residual lymph node structure and has been reported as a poor prognostic factor in gastric cancer. The aim of this study is to assess the prognostic value of extranodal metastasis, especially from the viewpoint of its anatomical distribution. METHODS: A total of 139 consecutive gastric cancer patients who underwent curative surgery with lymph node metastasis between 2008 and 2009 were included. Clinicopathological features and patient survival outcomes were retrospectively assessed. Patients with extranodal metastasis were subdivided into two groups: perigastric extranodal metastasis, located near the perigastric area (#1-#7 according to the Japanese classification of gastric carcinoma 15th edition), and extra-perigastric extranodal metastasis, located alongside the major vessels (#8-#12). RESULTS: Extranodal metastasis was found in 51 patients (37%), and it was more frequent in those with bulky, ≥pT3, and pStage III tumors. All patients with extra-perigastric extranodal metastasis had recurrence, resulting in a 0% 5-year overall survival rate, which was significantly worse than that of patients with perigastric extranodal metastasis (59%), or those without extranodal metastasis (84%; P < 0.001). Multivariable analysis identified the presence of extra-perigastric extranodal metastasis as an independent poor prognostic factor. CONCLUSIONS: Extranodal metastasis, especially extra-perigastric extranodal metastasis, was a pivotal poor prognostic factor in node-positive gastric cancer. Recognizing extra-perigastric extranodal metastasis would help provide optimal therapeutic options to these high-risk patients.

[Hairy cell leukemia complicated by bone marrow necrosis following cladribine administration].

Classic hairy cell leukemia (classic HCL) is a rare disease associated with indolent mature B-cell lymphoma. A 50-year-old man presented with pancytopenia for 3 years and was diagnosed with classic HCL because his lymphoid cells showed a hairy morphology with oval nuclei and indistinct nucleoli both in the peripheral blood and bone marrow (BM) smears. Flow cytometric analysis revealed that these cells expressed CD11c, CD25, and CD103, and the Sanger sequence method detected BRAF V600E mutation. Cladribine (0.09 mg/kg/day) was initiated for 7 days via continuous intravenous injection. On day 13, the patient died from bloodstream infection caused by methicillin-resistant Staphylococcus epidermidis. Autopsy findings revealed BM necrosis without residual leukemia cells caused by classic HCL, severe infection, and agents, such as cladribine and granulocyte-colony stimulating factor; however, its cause remained undetermined. Both early diagnosis and immediate clinical intervention are required to improve the clinical outcomes in classic HCL. The cause of hematopoiesis disturbance should also be identified using BM biopsy or magnetic resonance imaging before initiating treatment in classic HCL with severe pancytopenia.

Growth patterns of small peripheral squamous cell carcinoma of the lung and their impacts on pathological and biological characteristics of tumor cells.

PURPOSE: The growth pattern of peripheral squamous cell carcinoma (SCC) of the lung is divided into two types: alveolar space-filling (ASF) growth and alveolar space-destructive (ASD) growth. The aim of this study was to investigate the clinicopathological differences between cancer cells displaying ASF and ASD growth. METHODS: We analyzed 155 patients with peripheral SCC measuring 30 mm or less in diameter. The proportion of ASF in the total tumor area (%ASF) was determined using digital image analysis. We examined the clinicopathological characteristics of the cancer cells and compared the immunophenotypes of high %ASF tumors (> 30%) and low %ASF tumors (0%). Finally, we analyzed the prognostic impact of ASD area with small SCC cases (≤ 2.0 cm, n = 72). RESULTS: Cases of high %ASF tumors showed significantly lower frequencies of lymphovascular invasion (p = 0.008). Immunohistochemical staining revealed that the expression score of laminin-5, invasive-related molecule, in cancer cells was significantly lower in high %ASF cases than in low %ASF cases (p = 0.001). Within the same tumor, laminin-5 expression in the ASF area was significantly lower than that in the ASD area (p = 0.001). The overall 5-year survival rate of patients with a larger ASD area (> 1.0 cm2) was significantly lower than that of patients with a smaller ASD area (≤ 1.0 cm2) (p = 0.017). CONCLUSIONS: In this study, we clearly showed that cancer cells presenting with ASF represents a "less invasive phenotype" in peripheral SCC.