Irradiated engineered tumor cell-derived microparticles remodel the tumor immune microenvironment and enhance antitumor immunity

Radiotherapy (RT), administered to roughly half of all cancer patients, occupies a crucial role in the landscape of cancer treatment. However, expanding the clinical indications of RT remains challenging. Inspired by the radiation-induced bystander effect (RIBE), we used the mediators of RIBE to mimic RT. Specifically, we discovered that irradiated tumor cell-released microparticles (RT-MPs) mediated the RIBE and had immune activation effects. To further boost the immune activation effect of RT-MPs to achieve cancer remission, even in advanced stages, we engineered RT-MPs with different cytokine and chemokine combinations by modifying their production method. After comparing the therapeutic effect of the engineered RT-MPs in vitro and in vivo, we demonstrated that tIL-15/tCCL19-RT-MPs effectively activated antitumor immune responses, significantly prolonged the survival of mice with malignant pleural effusion (MPE), and even achieved complete cancer remission. When tIL-15/tCCL19-RT-MPs were combined with PD-1 monoclonal antibody (mAb), a cure rate of up to 60% was achieved. This combination therapy relied on the activation of CD8+ T cells and macrophages, resulting in the inhibition of tumor growth and the establishment of immunological memory against tumor cells. Hence, our research may provide an alternative and promising strategy for cancers that are not amenable to conventional RT.

Expression of EGFR, PD-L1, and the mismatch repair proteins before and following therapy in malignant serous effusions with metastatic high-grade serous tubo-ovarian carcinoma

AIM

To compare the immunochemical expression of EGFR, PD-L1, and the mismatch repair (MMR) proteins MLH1, PMS2, MSH2, and MSH6 between matched malignant effusions obtained before and following the administration of chemotherapy in patients with high-grade serous tubo-ovarian carcinoma (HGSC).

METHODS

In the enrolled HGSCs, matched formalin-fixed and paraffin-embedded cell blocks (CBs) from effusions sampled before (treatment-naïve patients) and during recurrence (following chemotherapy administration), in addition to their matched HGSC tissues obtained from the ovaries at initial diagnosis (treatment-naïve patients), were subjected to EGFR, PD-L1, and MMR immunochemical analysis.

RESULTS

EGFR was more often overexpressed in effusions obtained after chemotherapy administration compared to both effusions (100% vs. 57.1%) and their matched tubo-ovarian tumors (100% vs. 7.1%) from treatment-naïve patients, respectively. EGFR immunochemistry was concordant in just 9.1% of the effusions sampled during recurrence and their paired ovarian samples before recurrence. Whereas all HGSC treatment-naïve samples (ovarian lesions and effusions) were PD-L1 negative, 3/11 (27.3%) malignant effusions obtained during recurrence showed PD-L1 overexpression. Lastly, none of the tested HGSC samples exhibited MMR deficiency.

CONCLUSION

Measuring biomarkers using CBs from malignant effusions may provide clinicians with significant information related to HGSC prognosis and therapy selection, especially in patients with resistance to chemotherapy.

Proteomics on malignant pleural effusions reveals ERα loss in metastatic breast cancer associates with SGK1-NDRG1 deregulation

Breast cancer (BCa) is a highly heterogeneous disease, with hormone receptor status being a key factor in patient prognostication and treatment decision-making. The majority of primary tumours are positive for oestrogen receptor alpha (ERα), which plays a key role in tumorigenesis and disease progression, and represents the major target for treatment of BCa. However, around one-third of patients with ERα-positive BCa relapse and progress into the metastatic stage, with 20% of metastatic cases characterised by loss of ERα expression after endocrine treatment, known as ERα-conversion. It remains unclear whether ERα-converted cancers are biologically similar to bona fide ERα-negative disease and which signalling cascades compensate for ERα loss and drive tumour progression. To better understand the biological changes that occur in metastatic BCa upon ERα loss, we performed (phospho)proteomics analysis of 47 malignant pleural effusions derived from 37 BCa patients, comparing ERα-positive, ERα-converted and ERα-negative cases. Our data revealed that the loss of ERα-dependency in this metastatic site leads to only a partial switch to an ERα-negative molecular phenotype, with preservation of a luminal-like proteomic landscape. Furthermore, we found evidence for decreased activity of several key kinases, including serum/glucocorticoid regulated kinase 1 (SGK1), in ERα-converted metastases. Loss of SGK1 substrate phosphorylation may compensate for the loss of ERα-dependency in advanced disease and exposes a potential therapeutic vulnerability that may be exploited in treating these patients.

Malignant pleural effusion and pericardial effusion, an unusual presentation of metastatic adenoid cystic carcinoma of the floor of mouth: A case report with cyto-histopathological correlation

Adenoid cystic carcinoma (ACC) is an uncommon tumour that represents 5%-10% of salivary gland tumours and 1% of all head and neck malignancies. It is characterised by a protracted clinical course with late metastasis and poor long-term prognosis. We report the case of a 38-year-old woman presenting with pulmonary and pleural metastases, on the background of ACC of the floor of mouth, which had been treated 4 years ago with surgical excision and radiotherapy. Cytological evaluation of the pleural effusion showed exfoliated ACC tumour cells. Despite palliative chemotherapy, the patient developed disease progression including metastatic spread to the pericardium, and died of disease within a year. This case illustrates an unusual presentation of ACC and highlights the importance of considering this entity when encountering a basaloid neoplasm in extra-salivary locations.

C1q+ tumor-associated macrophages contribute to immunosuppression through fatty acid metabolic reprogramming in malignant pleural effusion

BACKGROUND

Although immune checkpoint blockade (ICB) therapy has shown remarkable benefits in cancers, a subset of patients with cancer exhibits unresponsiveness or develop acquired resistance due to the existence of abundant immunosuppressive cells. Tumor-associated macrophages (TAMs), as the dominant immunosuppressive population, impede the antitumor immune response; however, the underlying mechanisms have not been fully elucidated yet.

METHODS

Single-cell RNA sequencing analysis was performed to portray macrophage landscape and revealed the underlying mechanism of component 1q (C1q)+ TAMs. Malignant pleural effusion (MPE) of human and mouse was used to explore the phenotypes and functions of C1q+ TAMs.

RESULTS

C1q+ TAMs highly expressed multiple inhibitory molecules and their high infiltration was significantly correlated with poor prognosis. C1q+ TAMs promote MPE immunosuppression through impairing the antitumor effects of CD8+ T cells. Mechanistically, C1q+ TAMs enhance fatty acid binding protein 5 (FABP5)-mediated fatty acid metabolism, which activate transcription factor peroxisome proliferator-activated receptor-gamma, increasing the gene expression of inhibitory molecules. A high-fat diet increases the expression of inhibitory molecules in C1q+ TAMs and the immunosuppression of MPE microenvironment, whereas a low-fat diet ameliorates these effects. Moreover, FABP5 inhibition represses the expression of inhibitory molecules in TAMs and tumor progression, while enhancing the efficacy of ICB therapy in MPE and lung cancer.

CONCLUSIONS

C1q+ TAMs impede antitumor effects of CD8+ T cells promoting MPE immunosuppression. Targeting C1q+ TAMs effectively alleviates the immunosuppression and enhances the efficacy of ICB therapy. C1q+ TAMs subset has great potential to be a therapeutic target for cancer immunotherapy.

Unexpected Clinical Outcome for Myxoinflammatory Fibroblastic Sarcoma, When Should They Be Considered High Grade?

Myxoinflammatory fibroblastic sarcoma (MIFS) is a rare tumor of soft tissue. It typically presents as a low-grade sarcoma with myxoid stroma, has a predilection for distal extremities, and displays a high propensity for local recurrence, but low metastatic potential. The risk factors associated with high-risk lesions metastasizing are poorly defined. In cases where the tumor metastasizes, therapeutic options are few, and death is rare. Our case discusses an aggressive MIFS that progressed from a painless lesion on a patient's calf, to her death from a malignant pleural effusion within 21 months. The 58-year-old woman presented with a mass on her left calf. It was excised and was originally thought to be a benign process. It re-grew quickly after the initial resection, and she underwent re-excision of the mass. The pathologic examination was consistent with an MIFS. Despite negative margins on her second resection and an attempt at local control with radiotherapy, it metastasized to her lungs within less than 2 years. This resulted in a malignant pleural effusion that caused her death. An MIFS is typically benign but can metastasize in atypical cases. Even if the disease is metastatic, it is unlikely to be the cause of death. Treatment of metastatic MIFS is poorly defined, but there are suggested therapies beyond surgical resection and radiotherapy. Successful treatment of an MIFS should include a high index of suspicion in extremity lesions, screening for metastasis, and possible targeted therapies based on tumor genomics.

The Detection of Immunity against WT1 and SMAD4P130L of EpCAM+ Cancer Cells in Malignant Pleural Effusion

Malignant pleural effusion (MPE) provides a liquid tumor microenvironment model that includes cancer cells and immune cells. However, the characteristics of tumor antigen-specific CD8⁺ T cells have not been investigated in detail. Here, we analyzed MPE samples taken from a patient with pancreatic cancer who received a dendritic cell vaccine targeting Wilms’ Tumor 1 (WT1) antigen over the disease course (two points at MPE^1st and 2^nd, two months after MPE1^st). Epithelial cell adhesion molecule (EpCAM)⁺ cancer cells (PD-L1⁻ or T cell immunoglobulin mucin-3, TIM-3⁻), both PD-1 or TIM-3 positive CD8⁺ T cells, and CD14⁺CD68⁺CD163⁺TIM-3⁺ macrophages increased from the MPE^1st to MPE^2nd. The ratio of WT1-specific cytotoxic lymphocytes (WT1-CTLs) to MPE CD8⁺ T cells and IFN-γ secretion of WT1-CTLs were reduced with disease progression. Coincidentally, the fraction of central memory T (T_CM) of WT1-CTLs was decreased. On the other hand, CD8⁺ T cells in response to SMAD4^P130L, which is homogeneously expressed in EpCAM⁺ cancer cells, were detected using in vitro expansion with the HLA-A*11:01 restrictive SVCVNLYH neoantigen. Furthermore, the CD8⁺ T cell response to SMAD4^P130L was diminished following remarkably decreased numbers of CD8⁺ T_CM in MPE samples. In conclusion, CD8⁺ T cells responding to WT1 or SMAD4^P130L neoantigen expressed in EpCAM⁺ pancreatic cancer cells were detected in MPE. A tumor antigen-specific immune response would provide novel insight into the MPE microenvironment.

Cytomorphological and immunohistochemical features of pancreatic ductal adenocarcinoma in serous fluids

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) represents the most common primary pancreatic malignancy. An understanding of the cytomorphologic features of conventional ductal adenocarcinoma and its variants is important to ensure accurate diagnoses.

METHODS

The clinicopathological and cytological data of serous fluids in PDAC patients were obtained from the electronic medical records and pathology database. All samples were analyzed and reclassified according to the "The International System for Reporting Serous Fluid Cytopathology" guidelines. Cytomorphologic features were examined with SurePath automatically prepared slides and stained using the Pap method in malignant (MAL) effusion specimens from 21 patients with PDAC. Immunocytochemical staining was conducted on 12 cell blocks from MAL PDAC effusion.

RESULTS

A total of 137 serous fluids specimens of PDACs were included, among which 61 (44.5%), 9 (6.6%), 13 (9.5%), 52 (38.0%), and 2 (1.5%) patients were classified into malignancy, suspicious for malignancy, atypia of undetermined significance, negative for malignancy and nondiagnostic groups, respectively. The key cytologic features for the conventional type of PDAC included cohesive clusters of ductal cells in glandular crowding and disorganized "drunken honeycomb" pattern or intercalated duct-like structure with anisonucleosis, cytoplasmic vacuoles, and concomitant "Indian-file" configuration. Undifferentiated carcinoma was comprised of enlarged, undifferentiated, pleomorphic MAL cells. Adenosquamous carcinoma could show glandular and/or squamous differentiation. Colloid carcinoma was composed of three-dimensional cancer cell clusters floating in thick mucin.

CONCLUSION

Crowding and disorganized "drunken honeycomb" pattern or intercalated duct-like structure with anisonucleosis, may represent an important clue for diagnosing PDAC in serous fluids. Immunocytochemical staining in combination with review of medical records and cytomorphological data can serve as useful adjuncts for distinguishing between PDAC and its variants.

Response to Chemical Pleurodesis in Children with Frequent Relapsing Nephrotic Syndrome Having Refractory Unilateral Pleural Effusion

Idiopathic nephrotic syndrome is one of the most common chronic renal disorders in children. Associated bilateral pleural effusion is common due to the transudative process as a result of hypoalbuminemia. However, unilateral pleural effusion is a rare phenomenon and at times, unresponsive even when the patients are in remission. Here, we report two cases of frequent relapse nephrotic syndrome presented as persistent unilateral pleural effusion responsive to chemical pleurodesis, which was done with bleomycin along with normal saline.

Malignant pleural effusion cell blocks are reliable resources for PD-L1 analysis in advanced lung adenocarcinomas: a concordance study with matched histologic samples

INTRODUCTION

In lung cancer patients presenting with malignant pleural effusion (MPE), cytology might represent the only source of tumor tissue for diagnosis and predictive biomarker testing. Programmed death ligand 1 (PD-L1) expression in tumor cells is a predictive biomarker for immunotherapy in non-small cell lung carcinomas and is tested using immunohistochemistry. However, knowledge of the validity of PD-L1 testing on MPE samples is limited. We evaluated the feasibility of immunocytochemistry (ICC) for PD-L1 in MPE cell blocks (CBs) and assessed the concordance in expression with patient-matched histologic samples.

MATERIALS AND METHODS

ICC for PD-L1 was performed on formalin-fixed paraffin-embedded CBs of MPE and patient-matched histologic samples, if available, using the automated Ventana PD-L1 SP263 assay. The tumor proportion score (TPS), based on partial or complete membranous tumor cell staining, was categorized as negative (<1%), low (≥1% to <50%), and high (≥50%). In CBs with any degree of PD-L1 expression, ICC for CD163 highlighting macrophages was performed to exclude nonspecific PD-L1 expression in macrophages. The CB PD-L1 TPS was compared with the TPS obtained from the patient-matched histologic samples.

RESULTS

Of 43 MPE CBs available, 25 were positive for PD-L1 (25 of 42; 59%), and 1 sample was inadequate. Of the 11 patient-matched histologic samples tested, the PD-L1 TPS categories were concordant for 10 of the 11 (91% concordance) cases.

CONCLUSIONS

PD-L1 expression in MPE CBs showed good concordance with expression in histologic samples and is feasible as a source for PD-L1 testing. The concurrent use of CD163 immunostains will aid in the manual assessment of PD-L1 TPS.

68Ga-Prostate-Specific Membrane Antigen-Avid Malignant Pleural Effusion in a Patient With Metastatic Adenoid Cystic Carcinoma and Concordance With 18F-FDG PET/CT

ABSTRACT

Adenoid cystic carcinoma (ACC) is a rare cancer that arises from salivary glands and other secretory glands. Pulmonary metastases are frequently observed in ACC patients with metastatic disease. Previous research showed that ACC often shows high PSMA uptake on 68Ga-PSMA-11 PET/CT. Here, we present PET images from an ACC patient with pulmonal, pleural metastases, and malignant pleural effusion, with comparable tracer uptake on 68Ga-PSMA-11 PET and 18F-FDG PET.

Quality of life in patients with malignant pleural effusion treated with an indwelling pleural catheter in an emerging country

BACKGROUND

The use of Indwelling Pleural Catheter (IPC) in the care of patients with Malignant Pleural Effusion (MPE) is well established, however studies involving public health systems of low and middle-income countries are still lacking. This study aimed to determine the effect of IPC on the respiratory symptoms and Quality of Life (QoL) of patients with MPE in the setting of a Brazilian public health system.

METHODS

From August 2015 to November 2019, patients with MPE underwent IPC placement and were prospectively followed. QoL and respiratory symptoms were assessed by the EORTC questionnaires (QLQ-30; LC13) and Visual Analogue Scale (VAS), respectively, at pre-treatment, 30 , and 60 days after IPC placement.

RESULTS

56 patients were enrolled with 57 catheters inserted. The mean age was 63 (23‒88) years, of which 17 (30%) were men and 39 (70%) were women. Breast 24 (42%) and lung 21 (37%) were the main primary neoplasms. Cellulitis was the most common complication and all patients recovered with appropriate antimicrobial therapy. QoL did not change significantly over time, however, the VAS showed a significant improvement in dyspnea (+1.2: -0.5; p = 0.001).

CONCLUSION

IPC relieves respiratory symptoms without compromising the QoL, with a low complication rate. It represents a suitable option for patients with MPE and short LE in an emerging country.

The future of medical thoracoscopy in the Kingdom of Saudi Arabia

Medical thoracoscopy (MT) has changed how we manage exudative pleural effusion. It is a minimally invasive procedure used as a diagnostic and therapeutic tool in pleural disease. Here, we report a case of a lymphocytic exudative pleural effusion that needed a pleural biopsy for diagnosis. Medical thoracoscopy was performed, a biopsy was taken, and adhesiolysis was performed. Medical thoracoscopy has been practiced for a while worldwide, but it has not been utilized in the Kingdom of Saudi Arabia and as we believe that it is useful in diagnosing exudative pleural effusions. It limits patients in hospital-stay and it may be less costly than surgical procedures. It is especially helpful in diagnosing and treating pleural effusions in elderly patients with multiple comorbidities. Such procedures are needed to ease ongoing financial constraints, and with the 2019 coronavirus disease (COVID-19) pandemic, less time in the hospital means better utilization of beds during the pandemic. Spreading the knowledge about this procedure and its availability in the country will improve the health services provided to the patients.

Fighting Fire With Fire: Oncolytic Virotherapy for Thoracic Malignancies

Thoracic malignancies are associated with high mortality rates. Conventional therapy for many of the patients with thoracic malignancies is obviated by a high incidence of locoregional recurrence and distant metastasis. Fortunately, developments in immunotherapy provide effective strategies for both local and systemic treatments that have rapidly advanced during the last decade. One promising approach to cancer immunotherapy is to use oncolytic viruses, which have the advantages of relatively high tumor specificity, selective replication-mediated oncolysis, enhanced antigen presentation, and potential for delivery of immunogenic payloads such as cytokines, with subsequent elicitation of effective antitumor immunity. Several oncolytic viruses including adenovirus, coxsackievirus B3, herpes virus, measles virus, reovirus, and vaccinia virus have been developed and applied to thoracic cancers in preclinical murine studies and clinical trials. This review discusses the current state of oncolytic virotherapy in lung cancer, esophageal cancer, and metastatic malignant pleural effusions and considers its potential as an emergent therapeutic for these patients.

Advances in pleural infection and malignancy

Pleural infection and malignancy are among the most common causes of pleural disease and form the mainstay of pleural practice. There has been significant research and increase in scientific understanding in these areas in the past decade. With regard to pleural infection, the rising incidence remains worrying. An increased awareness allowing earlier diagnosis, earlier escalation of therapy and the use of validated risk stratification measures may improve outcomes. In pleural malignancy, research has enabled clinicians to streamline patient pathways with focus on reducing time to diagnosis, definitive management of malignant pleural effusion and achieving these with the minimum number of pleural interventions. Trials comparing treatment modalities of malignant pleural effusion continue to highlight the importance of patient choice in clinical decision-making. This article aims to summarise some of the most recent literature informing current practice in these two areas.

Ovarian carcinomatosis in a dog managed with surgery and intraperitoneal, systemic, and intrapleural chemotherapy utilizing indwelling pleural access ports

A 3-year-old Weimaraner dog was presented with bilateral papillary ovarian carcinoma and abdominal carcinomatosis. Treatment included ovariectomy, intraperitoneal cisplatin, and systemic carboplatin. Pleural carcinomatosis 473 days following surgery was treated with intrapleural cisplatin through indwelling pleural access ports. Euthanasia occurred 1154 days following surgery due to malignant pleural effusion without peritoneal effusion.

T-Cell Lymphoblastic Lymphoma Presenting with a Breast Mass

Lymphomas secondarily involving the breast are uncommon, although they do represent the largest group of tumors metastatic to breast. A 20-year-old female with lymphoblastic lymphoma (LBL) presented here with 3 month history of weight loss, night sweats, fatigue and a mass in her left breast. Her physical examination revealed a left breast mass, lympadenopathy, bilateral pleural effusion and hepatomegaly. WBC count was 17,710/mm3 and LDH was mildly elevated. Breast ultrasound showed a 1.7 cm mass in the inner lower quadrant of left breast. Biopsy of the breast mass showed diffuse infiltration with small, round atypical cells which did not stain with CD20, CD43, CD34, cytokeratine and were positive for CD3. She was diagnosed as leukemic phase of a precursor T-cell LBL and treated with 6 cycles of CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone), intrathecal methotrexate and cranial radiotherapy, achieving a complete response. She then was started on maintenance therapy. Four months later she returned with CNS involvement and was started on induction treatment. She had a very aggressive course of disease and died only 12 months after diagnosis. Breast involvement is very rarely seen in precursor T-cell LBL/ALL and in this patient occurred secondarily as part of widespread disease.

Establishment and characterization of two distinct malignant mesothelioma cell lines with common clonal origin

We describe two newly established malignant mesothelioma (MM) cell lines derived from a pleural effusion of a male. One cell line, designated as MM-Z03E, reveals an epithelioid cobblestone morphology, while the second one, designated as MM-Z03S and subcloned after in vivo selection, exhibits a sarcomatoid storiform growth pattern. Both cell lines showed the immunologic profile characteristic for MM (i.e., expression of cytokeratin, CK18, calretinin, and vimentin in both phenotypes). Cytogenetics, multicolor fluorescence in situ hybridization, comparative genomic hybridization, and oligonucleotide array CGH were performed on both cell lines. Aberrations shared by both cell lines included chromosomal losses of 1q34 approximately qter, 4, 9p, 10p, 13, 14, 16q, 18, and 22, as well as a complex structural aberration involving chromosome 17. Aberrations exclusive to MM-Z03E included gains of 3q11q27 and 5p, while gain of 9q and losses of 3q27qter, 11q, and 18 in MM-Z03S were exclusive to MM-Z03E. Both cell lines were able to develop solid transplant tumors in nude mice within 16 weeks, and immunophenotyping of tumor xenografts revealed an overall retained expression profile of the markers used. Remarkably, one xenograft from MM-Z03E revealed overexpression of p53 and widely invasive growth. In conclusion, both cell lines are useful in vivo and in vitro model systems to study the underlying genetic mechanisms of biphasic differentiation in MM, which can be of certain value considering the increasing relevance of assessing MM tumor biology for the clinical management of this disease.

Use of the Collagen Gel Droplet Embedded Drug Sensitivity Test to Determine Drug Sensitivity against Ovarian Mature Cystic Teratoma with Malignant Transformation to Adenocarcinoma: A Case Report

BACKGROUND

The collagen gel droplet embedded drug sensitivity test (CD-DST) is a new anticancer drug sensitivity test that only requires a small number of cells. We report the use of this test in the choice of adjuvant chemotherapy for treatment of a rare case of ovarian cancer involving malignant transformation of ovarian mature cystic teratoma.

CASE REPORT

The patient was a 70-year-old female with an ovarian tumor, pleural effusion, carcinomatous ascites and a chest wall tumor. The histopathological diagnosis was adenocarcinoma, mature cystic teratoma with malignant transformation, stage IV. Paclitaxel/carboplatin therapy was selected as adjuvant chemotherapy based on CD-DST results. Upon completion of 6 courses, no increases in carcinomatous ascites or recurrent lesions were evident, and the chest wall tumor had disappeared completely.

CONCLUSION

The CD-DST may be particularly useful for selecting preoperative chemotherapeutic drugs for patients with ovarian cancer in which the histological type of the primary tumor is unknown.

[Cardiac tamponade in a neonate with cardiac tumour]

A case of a neonate with a life-threatening cardiac tamponade due to cardiac tumour is presented. Pericardiocentesis was performed and 300 ml of purulent fluid was evacuated. Pericardial drainage was undertaken. Six months later cardiac tamponade recurred and was again successfully treated with pericardial drainage. A subsequent 10-month follow-up was uneventful. Diagnosis and treatment of cardiac tumours associated with pericardial effusion are discussed.

Use of imaging in the management of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is an increasingly prevalent tumour. The death rate associated with MPM is predicted to peak in the next 10 years, although radiologists and clinicians will be encountering cases for the next few decades. Contrast-enhanced CT is an established technique for evaluating suspected malignant pleural disease, but MPM can be reliably diagnosed only by histological sampling. However, even with adequate sampling and the use of immunocytochemistry, histological diagnosis is known to be difficult; definitive diagnosis may involve a combination of clinical presentation, radiological and histological appearances. Percutaneous biopsy is a promising technique for sampling the pleura. In view of its pattern of growth, MPM is a challenging disease to image by any method, and it behaves quite differently from lung cancer. This review aims to highlight the practical aspects of assessing malignant pleural mesothelioma.

Implications of P16/CDKN2A deletion in pleural mesotheliomas

Homozygous deletion of P16/CDKN2A is found in approximately 75% of mesotheliomas amd may be the most common genetic alteration in this cancer. In terms of diagnostic applications, its high prevalence makes it a useful marker to distinguish malignant mesothelial cells from benign reactive ones in pleural fluid cytologic preparations. In terms of prognosis, P16/CDKN2A loss is associated with more aggressive clinical behavior in mesotheliomas. The homozygous co-deletion of MTAP, encoding the enzyme methylthioadenosine phosphorylase, in approximately 90% of mesotheliomas with P16/CDKN2A loss has potential therapeutic applications because MTAP-deficient tumors may be responsive to inhibitors of de novo AMP synthesis. Finally, global gene expression profiling using Affymetrix U133A chips finds few gene expression correlates of P16/CDKN2A deletion in pleural mesothelioma, consistent with its non-transcriptional mode of direct action through regulation of cell cycle-related kinase signaling.

Myeloid sarcoma occurring in the maxillary gingiva: a case without leukemic manifestations

Myeloid sarcoma (MS) is a localized extramedullary mass of immature granulocytic cells that usually occurs in patients with acute myeloid leukemia (AML) or myeloproliferative disorders. It may rarely precede peripheral blood or bone marrow involvement, presenting a diagnostic challenge. Although MS may be found in any location, an intraoral occurrence is rare. In this report we describe a rare case of a patient with nonleukemic MS of the maxillary gingiva. The histologic specimen was first interpreted as non-Hodgkin's lymphoma. The correct diagnosis was reached after extensive immunohistologic studies. The malignant cells were myeloperoxidase positive, lysozyme positive, CD45+, CD68+, CD3-, CD10-, CD19-, CD20-, CD30-, CD34-, CD56-, CD79a-, S100-, and chloroacetate esterase negative. Induction therapy with FLAND (fludarabine, Ara-C, mitoxantrone, and dexamethasone) was started, but the patient did not achieve a remission. Some weeks later, the patient presented pleural effusion and paralysis of the seventh cranial nerve on the left side. She died a few days later. The present case indicates the importance of a correct initial diagnosis for adequate therapy, which is often delayed because of a high misdiagnosis rate. If the MS is treated without intensive chemotherapy for AML as soon as possible, the prognosis will be poor.

FISH cytogenetics and prognosis in breast and non-small cell lung cancers

BACKGROUND

Interphase cytogenetics by fluorescence in situ hybridization (FISH) has been demonstrated to be a valuable diagnostic tool in effusions from patients with solid tumors. As the next step, we investigated whether certain patterns of numeric aberrations in malignant effusion cells supply prognostic information.

METHODS

From a large series of effusions from patients with solid tumors, 55 effusions from breast cancer and 39 effusions from non-small cell lung cancer (NSCLC) were classified as malignant by cytology or FISH. Tumor cells were classified as FISH aneuploid for chromosome 11 and/or 17 or as not aneuploid. Predominant cytogenetic anomalies and patterns of intratumor cytogenetic heterogeneity were brought in relation to overall survival rate.

RESULTS

There was no difference with respect to overall survival rate when effusions with or without aneuploidy for chromosomes 11 and 17 were compared. Likewise, in effusions with aneuploidy, there was no difference in overall survival rate among patients with different modal chromosome copy numbers (e.g., trisomy vs. tetrasomy 11) or among patients with a low or high grade of intratumor complexity (defined by the intratumor heterogeneity of FISH aneuploidy). In breast cancer, aneuploidy with gain of chromosome 11 was associated with a significantly superior survival rate, suggesting that amplification of chromosome 11 DNA is associated with a less aggressive phenotype.

CONCLUSIONS

Simple chromosomal changes as determined by FISH, such as gain of chromosome 11 copy numbers in breast cancer, may be prognostic. Prospective studies in primary tumors that classify distinct prognostic groups by FISH cytogenetics are warranted.

Stromal-derived factor-1alpha/CXCL12-CXCR 4 axis is involved in the dissemination of NSCLC cells into pleural space

Malignant pleural effusion (PE) is one of the poor prognostic factors in non-small cell lung cancer (NSCLC), and the detailed mechanism of the malignant PE formation is not fully elucidated. Recently, CXCR4, a receptor for chemokine stromal-derived factor-1alpha (SDF-1alpha) that can induce chemotaxis of cells, was reported to be expressed on NSCLC. In this study, we hypothesized that the SDF-1alpha/CXCR4 axis may be involved in the dissemination of malignant cells into pleural space, and investigated its expression, function, and signaling pathway using NSCLC cell lines and clinical samples from 43 patients with NSCLC with malignant PE. We found functional expression of CXCR4 on NSCLC cell lines, and also found that SDF-1alpha could induce migration via phosphatidylinositol 3 (PI-3) kinase- and p44/42 mitogen-activated protein kinase-dependent manner. The SDF-1alpha levels in malignant PE were significantly higher than those in transudate PE and showed a significant positive correlation with PE volumes. The sensitivity and specificity for prediction of recurrence of malignant PE was 61.5% and 83.3%, respectively (cutoff SDF-1alpha = 2,500 ng/ml), and better than those using pH of PE. Cancer cells in malignant PE expressed CXCR4, and mesothelial cells of the pleura stained positive for SDF-1alpha. The SDF-1alpha/CXCR4 axis is involved in the dissemination of NSCLC cells into pleural space.

Doxil-induced regression of pleuro-pulmonary metastases in a patient with malignant meningioma

Metastatic meningioma is a rare disease, which has no effective chemotherapy. We report on a treatment of this condition with Doxil, a liposomal doxorubicin formulation. A 60-year-old woman with massive pleuro-pulmonary metastases from recurrent cranial meningioma was treated with Doxil (50-37.5 mg/m2) for 18 months with near-complete resolution of metastases and disappearance of pleural fluid. The only significant toxicities observed were stomatitis and hand-foot syndrome, which resolved with dose reduction and increase of dosing intervals. Doxil was cleared very slowly in this patient with a monoexponential half-life of 108 h. The patient remains in near-complete response for 6 months after treatment discontinuation. This is the first report on an effective chemotherapy in a patient with typical metastatic meningioma. The exact mechanism accounting for such an effective drug action is not clear, but may be related to a particularly high microvascular permeability to the liposome carriers in these metastatic lesions.

Anti-CD20 monoclonal antibody treatment of human herpesvirus 8-associated, body cavity-based lymphoma with an unusual phenotype in a human immunodeficiency virus-negative patient

Human herpesvirus 8 (HHV-8), or Kaposi's sarcoma-associated herpesvirus, is a gammaherpesvirus first detected in Kaposi's sarcoma tumor cells and subsequently in primary effusion lymphoma (PEL) tumor cells and peripheral blood mononuclear cells from PEL patients. PEL has been recognized as an individual nosologic entity based on its distinctive features and consistent association with HHV-8 infection. PEL is an unusual form of body cavity-based B-cell lymphoma (BCBL). It occurs predominantly in human immunodeficiency virus (HIV)-positive patients but occasionally also in elderly HIV-negative patients. We describe a case of PEL, with ascites, bilateral pleural effusions, and a small axillary lymphadenopathy, in a 72-year-old HIV-negative man. PCR performed on a lymph node specimen and in liquid effusion was positive for HHV-8 and negative for Epstein-Barr virus. The immunophenotype of the neoplastic cells was B CD19+ CD20+ CD22+ with coexpression of CD10 and CD23 and with clonal kappa light chain rearrangement. The patient was treated with Rituximab, a chimeric (human-mouse) anti-CD20 monoclonal antibody. Thirteen months later, the patient continued in clinical remission. This is the first report of an HHV-8-associated BCBL in an HIV-negative patient in Argentina.

Bilateral metastatic carcinoma of the breast from primary ovarian cancer

We report a case of ovarian cancer with metastasis to both breasts and axillary lymph nodes and the vaginal cuff. A 41-year-old previously hysterectomized women presented with pelvic mass and malignant pleural effusion. During the courses of chemotherapy; bilateral breast nodules, and bilateral axillary lymphadenopathies and a nodule in the vaginal cuff were identified. The biopsy of both breasts, axillary lymph nodes and the nodule in the vaginal cuff revealed papillary serous cystadenocarcinoma. Immunohistochemical staining of breast specimens were positive for ovarian tumor marker CA-125.

Primary effusion lymphoma with B-cell phenotype

We describe here a case of primary effusion lymphoma that occurred in a 78-year-old woman. She was successively treated with prednisolone but died 15 months after the diagnosis of primary effusion lymphoma. The immunohistochemistry revealed the neoplastic cells to be CD19(+), CD20(+), CD21(+), Sm-Ig(+), and HLA-DR(+). This patient exhibited clonal IgH and clonal kappa light chain gene rearrangement, indicating a B-cell origin. The present case was distinguished from the majority cases of HHV-8-positive primary effusion lymphoma. Here we present clinical details of response to therapy in this case.

Bcr-Abl with an SH3 deletion retains the ability To induce a myeloproliferative disease in mice, yet c-Abl activated by an SH3 deletion induces only lymphoid malignancy

The bcr-abl oncogene plays a critical role in the pathogenesis of chronic myelogenous leukemia (CML). The fusion of Bcr sequences to Abl constitutively activates the Abl protein tyrosine kinase. We have recently shown that expression of Bcr-Abl in bone marrow cells by retroviral transduction efficiently induces in mice a myeloproliferative disease resembling human CML and that Abl kinase activity is essential for Bcr-Abl to induce a CML-like myeloproliferative disease. However, it is not known if activation of the Abl kinase alone is sufficient to induce a myeloproliferative disease. In this study, we examined the role of the Abl SH3 domain of Bcr-Abl in induction of myeloproliferative disease and tested whether c-Abl activated by SH3 deletion can induce a CML-like disease. We found that Bcr-Abl with an Abl SH3 deletion still induced a CML-like disease in mice. In contrast, c-Abl activated by SH3 deletion induced only lymphoid malignancies in mice and did not stimulate the growth of myeloid colonies from 5-fluorouracil-treated bone marrow cells in vitro. These results indicate that Bcr sequences in Bcr-Abl play additional roles in inducing myeloproliferative disease beyond simply activating the Abl kinase domain and that functions of the Abl SH3 domain are either not required or redundant in Bcr-Abl-induced myeloproliferative disease. The results also suggest that the type of hematological neoplasm induced by an abl oncogene is influenced not only by what type of hematopoietic cells the oncogene is targeted into but also by the intrinsic oncogenic properties of the particular abl oncogene. In addition, we found that DeltaSH3 c-Abl induced less activation of Akt and STAT5 than did Bcr-Abl, suggesting that activation of these pathways plays a critical role in inducing a CML-like disease.

Fibrous pleural tumour producing 171 litres of transudate

Localized fibrous tumours of the pleura (or localized benign mesothelioma) are rare, and in most cases, asymptomatic. This report describes a 48 yr old female with a right-sided fibrous pleural tumour, which produced 171 L of transudate before a correct diagnosis was reached. The tumour was surgically removed and the transudation stopped immediately.

Lactate dehydrogenase activity in the diagnosis of malignant effusions

Enzyme assays in a series of 38 cases of pleural effusion and in 10 cases of ascites associated with malignant lesions and of 24 of pleural effusion and of five of ascites of benign origin do not support the suggestion that the estimation of the fluid lactate dehydrogenase serum ratios in pleural and peritoneal effusions is of value in the diagnosis of malignancy.