Cytology cell blocks are suitable for immunohistochemical testing for PD-L1 in lung cancer.

Background: PD-L1 immunohistochemistry (IHC) testing is usually carried out on tissue blocks from core needle biopsy or surgical resections. In this study, we assessed the feasibility of using cytology cell blocks for PD-L1 IHC assay. Methods: A total of 1419 consecutive cases of non-small-cell lung cancer (NSCLC), including 371 cytology cell blocks, 809 small biopsies, and 239 surgical specimens, were included in the study. The cytology cell blocks were prepared with formalin only, methanol/alcohol only or both. PD-L1 expression was examined by staining with Dako PD-L1 IHC 22C3 pharmDx kit. A Tumor Proportion Score (TPS) was categorized as <1%, 1%-49% and ≥50% tumor cells. A total of 100 viable tumor cells were required for adequacy. Results: Of the cytology cell blocks, 92% of the specimens had an adequate number of tumor cells, not significantly different from small biopsies. The rate of TPS ≥50% differed between sample types and was observed in 42% of cytology cell blocks versus 36% of small biopsies (P = 0.04), and 29% of surgical resections (P = 0.001). The fixative methods did not affect the immunostaining, with overall PD-L1 high expression (TPS ≥50%) rates of 42% in formalin-fixed specimens versus 40% in specimens with combined fixation by methanol/alcohol and formalin (NS). The PD-L1 high expression rate was not associated with EGFR, ALK or KRAS molecular alterations. Higher stage (IV) was associated with higher PD-L1 TPS (P= 0.001). Conclusion: Our results show that when the TPS ≥50% is used as the end point, PD-L1 IHC performs well with cytology cell blocks. Cell blocks should be considered as a valuable resource for PD-L1 testing in advanced NSCLC. The clinical significance of higher PD-L1 IHC scores in cytology specimens needs to be evaluated prospectively.

The metastatic site does not influence PD-L1 expression in advanced non-small cell lung carcinoma.

INTRODUCTION: PD-L1 expression by immunohistochemistry (IHC) testing with Tumor Proportion Score (TPS) ≥50% and ≥1% is required to be eligible for first- and second-line Pembrolizumab treatment for metastatic non-small cell lung cancer (NSCLC) respectively. Stage IV NSCLC often presents with metastasis to multiple distant sites which are easily accessible for biopsy. Knowing whether PD-L1 IHC TPS can be indifferently measured from different metastatic site is therefore an important clinical question. In this study, we evaluated PD-L1 expression in NSCLC from varied distant metastatic sites. METHODS: A total of 580 NSCLC specimens of distant metastases were retrieved for study, including 35 paired samples from two different metastatic sites. The metastatic sites included brain, bone, remote lymph nodes, serous membranes (pleura, pericardium and peritoneum), extra-thoracic solid organs and skin/soft tissues. The samples were cytology cell blocks, small biopsies or surgical resections. IHC was performed using Dako PD-L1 IHC 22C3 pharmDx. A total of 100 viable tumor cells was required for adequacy. TPS ≥ 50% and 1-49% were defined as high and low PD-L1 expression respectively. RESULTS: PD-L1 TPS scores were not significantly different across a range of distant metastatic sites nor between metastases in paired samples. CONCLUSION: Our results suggest that the PD-L1 TPS scoring is similar across different metastatic sites and any site biopsied will yield necessary information for guiding clinical management.

TRAF4 overexpression is a common characteristic of human carcinomas.

Tumor necrosis factor receptor (TNFR) associated factor 4 (TRAF4) was initially identified as a gene amplified and overexpressed in breast carcinomas. Our aim was to evaluate whether TRAF4 protein overexpression exists in other cancer types. Immunohistochemistry analysis of tumor samples from 623 patients with 20 different tumor types showed that TRAF4 was overexpressed in 268 tumors (43%), including 82 of 137 lung adenocarcinomas (60%). Interestingly, 32 primary tumors and their matching metastases exhibited mostly similar TRAF4 expression pattern. TRAF4 protein overexpression was limited to cancer cells and the subcellular localization was consistently cytoplasmic in a large majority of cases. To investigate changes in TRAF4 gene copy number, 125 cases from six different types of carcinomas were also analysed by fluorescence in situ hybridization. Out of the 28 cases (22%) showing an increased TRAF4 gene copy number, 23 (82%) were overexpressing the protein. Thus, TRAF4 gene amplification is one of the mechanisms responsible for TRAF4 protein overexpression in human cancers. Considering that TRAF4 is located at 17q11.2 in a region of amplification devoid of known oncogenes and is commonly overexpressed in cancer, our data support an oncogenic role for TRAF4.

[Pneumothorax in women and thoracic endometriosis]. / Pneumothorax de la femme et endométriose thoracique.

Thoracic endometriosis has been considered a rare clinical condition but it is probably underestimated in the literature. Various clinical symptoms may occur but the most frequent are catamenial pneumothoraces. Four main clinical conditions may reveal thoracic endometriosis: catamenial pneumothorax, catamenial haemothorax, catamenial haemoptysis and endometrial nodules in the lung. Catamenial pneumothoraces are the most frequent manifestation, characterized, in the majority of the cases, by right side localization and diaphragmatic abnormalities (perforations and/or nodules). The resection of suspected areas of visceral or parietal pleural endometriosis, as well as partial resection of the diaphragm in the case of nodules and/or perforations, allows the histological diagnosis of endometriosis. Because of the high recurrence rate, treatment of catamenial pneumothoraces should combine surgery and hormonal therapy.

An unusual case of hamartomatous polyposis with malignancy complication in a patient with ulcerative colitis treated with golimumab.

We report an unusual case of hamartomatous polyposis with malignant complications in a patient with ulcerative colitis on golimumab and previous thiopurine therapy. This patient was evaluated for iron deficiency anemia and underwent hemicolectomy for extensive right-side predominant inflammatory pseudopolyps. Anemia persisted post-colectomy and subsequent gastroscopy showed a fungating polypoid lesion along with numerous carpet-like strawberry appearing polyps in the stomach extending from the gastro-esophageal junction to the distal part of the antrum, necessitating a gastrectomy. Histology showed extensive hamartomatous-like polyps with adenocarcinoma and nodal metastases. Presence of alopecia totalis and hamartomas in this patient raise the possibility of Cronkhite-Canada Syndrome although this may also represent an undescribed hamartomatous polyposis associated with ulcerative colitis. Even though thiopurine analogue and anti-tumor necrosis factor agents have not been associated with increased risk of solid tumors, immunosuppression in patients with extensive polyposis should be cautiously used due to the potential accelerated malignancy risk. This case also highlights the importance of performing additional imaging of the gastrointestinal tract, in inflammatory bowel disease patients with anemia, particularly if the severity is incongruent with disease activity.

High-dose chemotherapy with autologous stem cell transplantation as first-line therapy for primary CNS lymphoma in patients younger than 60 years: a multicenter phase II study of the GOELAMS group.

The optimum treatment of primary CNS lymphoma (PCNSL) is not yet determined. The objective of this study was to assess the safety and efficacy of initial methotrexate-based chemotherapy followed by high-dose chemotherapy (HDT) with autologous stem cell transplantation (ASCT) in patients with newly diagnosed PCNSL. Twenty-five patients received two courses of initial chemotherapy combining methotrexate, etoposide, carmustine and methylprednisolone, and one course of ifosfamide-cytarabine followed by peripheral stem cell collection. Seventeen responsive patients then received HDT using carmustine, etoposide, cytarabine and melphalan with autologous stem cell rescue. After ASCT for responding patients or after salvage therapy for non-responders, whole brain radiation therapy at a dose of 30 Gy was delivered. The objective response rate to the induction chemotherapy was 84%. Four of the 21 responding patients did not have ASCT because of toxicity or refusal. With a median follow-up time of 34 months, the projected event free survival rate is 46% at 4 years. Projected overall survival is 64% at 4 years. Sixteen patients are actually in continuous complete response. No evidence of late treatment-related toxicity was observed. This treatment approach appears feasible in newly diagnosed PCNSL with encouraging results.

[Physiopathogenic aspects of HIV-associated primary brain lymphomas]. / Les lymphomes cérébraux primitifs associés au SIDA: aspects physiopathogéniques.

HIV-associated Primary brain lymphomas (PBLs) are usually diffuse, large B-cell lymphomas (DLBCLs). In contrast to those occurring in immunocompetent patients, nearly all HIV-associated PBLs are associated with Epstein-Barr virus (EBV). Since viral latency proteins are target antigens for anti-viral cytotoxic T lymphocytes, the double immunodeficiency (HIV infection, central nervous system microenvironment) favors the expression of viral latency proteins (LMP-1, EBNA2). These proteins play a major role in immortalization and transformation of infected B lymphocytes through cell cycle activation and apoptosis inhibition.

Perioperative analysis of biopsies issued from mediastinoscopy.

BACKGROUND: The objective of this study was to evaluate frozen sections of samples obtained at mediastinoscopy for their clinical usefulness. METHODS: This study retrospectively reviewed the records of all patients who underwent mediastinoscopy with perioperative frozen sections in a 1-year period. RESULTS: A total of 123 consecutive patients underwent the procedure. There were no false-positive results. Of the 71 malignant proliferations, 67 were diagnosed from frozen sections. The technique never failed to establish the absence of mediastinal nodal involvement in patients with suspected or proven lung tumors and enlarged nodes (n = 18) who underwent immediate thoracotomy. Frozen sections allowed recognition (n = 36) or strong suspicion (n = 4) of N2 disease in patients subsequently treated by induction chemotherapy. The technique never failed to establish the nonresectability of lung cancer in patients for whom this condition was suspected perioperatively (clinical stage IIIb; n = 10). CONCLUSIONS: Mediastinoscopy with frozen sections remains an extremely useful tool for the management of paratracheal or subcarinal mediastinal disease.

AIDS-related primary brain lymphomas: histopathologic and immunohistochemical study of 51 cases. The French Study Group for HIV-Associated Tumors.

Fifty-one cases of acquired immunodeficiency syndrome (AIDS)-related primary brain lymphomas (AR-PBL) were investigated for clinical characteristics; human immunodeficiency virus (HIV)-associated disorders; histopathologic features; immunophenotype; Epstein-Barr virus (EBV) infection; and, when frozen tissue was available, oncogene rearrangements. AR-PBL occurred late in the course of AIDS and were usually associated with other systemic or cerebral disorders and with a low level of CD4 lymphocytes. All cases were high grade lymphomas according to the Working Formulation or updated Kiel classification, and often displayed a multifocal pattern. Thirty cases were classified as immunoblastic with plasmacytic differentiation, 18 cases were large cell lymphomas with an immunoblastic component or centroblastic polymorphic lymphomas, and 2 were small noncleaved non-Burkitt lymphomas (Working Formulation). This latter category is classified as Burkitt's-like lymphoma in the REAL nomenclature. One case could not be classified because of necrosis. AR-PBL showed a high level expression of activation and adhesion molecules. The presence of EBV was detected in most cases, and, when PCR was used, this was a constant finding. bcl-2 oncoprotein and latent membrane protein-1 (LMP-1) were strongly expressed. None of the tested cases expressed p53, or were rearranged for bcl-2 or c-myc oncogenes. This study confirms the immunophenotypic specificity of AR-PBL, which may reflect the special immune status of the brain.

Primary central nervous system lymphomas in 72 immunocompetent patients: pathologic findings and clinical correlations. Groupe Ouest Est d'étude des Leucénies et Autres Maladies du Sang (GOELAMS)

We reviewed 72 primary central nervous system lymphomas occurring in immunocompetent patients. The cases were reviewed for clinical data, histology, immunophenotype, bcl-2 and p53 expression, and Epstein-Barr virus association. Follow-up was available for 40 patients included in the Groupe Ouest Est d'étude des Leucénies et Autres Maladies du Sang (GOELAMS) lymphomes cérébraux primitifs (LCP 88) trial. Each diagnosis, requiring a consensus among at least 3 pathologists, was performed according to the recent Revised European-American Lymphoma classification and equivalents in the updated Kiel classification. Tumors were predominantly classified as diffuse large B-cell lymphomas. There were 3 T-cell lymphomas and 1 Hodgkin lymphoma. The proteins bcl-2 and p53 were expressed in 35% and 16% of the tested cases, respectively. Epstein-Barr virus was not found by in situ hybridization except in the case classfied as a cerebral localization of Hodgkin disease. No significant association was found between subtypes, bcl-2 or p53 expression, and patient survival. From the standpoint of their biologic characteristics, primary central nervous system lymphomas are very similar to systemic diffuse large B-cell lymphomas. In contrast to AIDS-related primary central nervous system lymphomas, primary central nervous system lymphomas are rarely associated with Epstein-Barr virus and in immunocompetent patients they express bcl-2 at a relatively low rate.

Morphological variability of tumour cells in T-cell-rich B-cell lymphoma. A histopathological study of 14 cases.

T-cell-rich B-cell lymphoma (TCRBCL) is an unusual lymphoma which is difficult to diagnose. A majority of reactive T-cells and numerous histiocytes mask the few large neoplastic B-cells. Fourteen cases of TCRBCL were studied in order to identify the main histological and cytological features useful for this diagnosis. Neoplastic cells are atypical and sometimes difficult to classify. Several types are seen; they are mostly centroblasts, which represent more than 50% of the tumour cells but are sometimes multilobated, immunoblasts- or Reed-Sternberg-like cells. Interestingly, at least two, and often three, types of tumour cell are present in all the cases. Epithelioid cells and histiocytes are always found and are often numerous. Hypervascularization and fibrosis are present in the majority of cases, but without annular bands. Necrosis is absent. All tumour cells express CD20 but EMA is expressed in less than half the cases. In two cases, the association of a diffuse large B-cell lymphoma in one site and a TCRBCL in another suggests that TCRBCL may be considered as a peculiar pattern of a diffuse large B-cell lymphoma with a strong stroma reaction. TCRBCL may not represent a clinicopathological entity.

Peroperative frozen section analysis of TTF-1 antigen expression.

BACKGROUND: The assessment of thyroid transcription factor 1 (TTF-1) expression is a useful way to investigate the origin of lung adenocarcinomas or large cell carcinomas when dealing with a solitary lung nodule in a patient with a history of extrathoracic cancer. However, if immunohistological analysis has not been performed before surgery, a peroperative frozen section may be insufficient to distinguish between a primary pulmonary tumour and a metastatic tumour. AIMS: To develop a technique for the rapid assessment of TTF-1 expression that could improve the ability of frozen section peroperative histological diagnosis to answer such questions. METHODS: A rapid immunohistochemical technique (lasting 30 minutes) to assess the expression of TTF-1 was developed and tested. RESULTS: Among the 45 interpretable cases, results of frozen section immunohistochemistry were similar to those found by the standard immunohistochemical technique for the expression of TTF-1. CONCLUSIONS: This technique enables TTF-1 to be analysed peroperatively, but further prospective studies are needed to assess its usefulness in routine practice.

Primary histiocytic sarcoma of the spleen associated with erythrophagocytic histiocytosis.

We report an exceptional case of a histiocytic sarcoma presenting as a primary isolated spleen tumor in a 71-year-old woman. The neoplastic cells in the cords and sinuses of the red pulp formed multiple lobulated tumors, which were detected in vivo by ultrasound scan. The medium cells, large cells and the giant cells expressed CD68, a histiocyte-associated marker, lysozyme and S100 protein. All these cells were negative for B- and T-cell markers, cytokeratins, melanosome markers (HMB45) and CD1a (Langerhans' cells). Many tumor cells displayed strong erythrophagocytosis and sometimes lymphocytophagocytosis. In addition, numerous histiocytes with morphology indistinguishable from reactive macrophages also exhibited a strong erythrophagocytosis, and were found in the tumor as well as in the normal splenic parenchyma. Despite multi-agent chemotherapy, the patient suffered from a relapse in the liver, with a rapid fatal outcome. A literature review showed that such a primary splenic presentation with multiple tumors is rare. In contrast, in systemic malignant histiocytosis, secondary spleen involvement occurs more frequently but with diffuse infiltration. The association with a reactive histiocytosis with erythrophagocytosis corresponds to "histiocytic medullary reticulosis", as previously described by Scott and Robb-Smith.

Myeloid sarcoma: clinical and morphologic criteria useful for diagnosis.

Extramedullary accumulation of myeloblasts or immature myeloid cells form tumors called myeloid sarcoma in the WHO classification. Such tumors develop in lymphoid organs, bone (skull, orbit, etc.), skin, soft tissue, various mucosae and organs, and the CNS. They may precede or occur concurrently with acute myeloid leukemia, or reveal blastic transformation of chronic myeloproliferative disorders or myelodysplastic syndromes. They may also reveal relapses in treated patients. They are constituted by a diffuse infiltrate made up of medium-to-large cells. The cells are difficult to identify. Imprints are very useful. Immunohistochemistry can help diagnose and distinguish four variants: granulocytic myeloperoxidase (MPO+, CD 68+ [KP1+/-, PGM1-] lysozyme+, CD 34+/-), monoblastic (MPO-, CD 68+, [KP1+, PGM1+] lysozyme+, CD 34-), myelomonoblastic (MPO-, CD 68+, [KP1+, PGM1+] lysozyme+, CD 34-), or megakaryoblastic (positivity for factor VIII, CD 61, CD 31). Immunohistochemistry sometimes demonstrates expression of CD 43, CD 7, CD 79a, and CD 56 (particularly the monoblastic variant with t[8;21]). Recently the demonstration of CD 99 and CD 117, which can now be done on paraffin sections, may be useful to identify blasts of granulocytic origin. The diagnosis is missed in about 50% of cases when immunohistochemistry is not used. Patients with myeloid sarcomas should be treated in the same way as patients with acute myeloblastic leukemia. Disease progression and prognosis are similar for the two conditions.

[Micrometastases in colonic cancers: diagnostic methods and prognostic elements]. / Les micrométastases dans les cancers coliques: méthodes diagnostiques et éléments pronostiques.

Micrometastasis are defined by the existence of cells or groups of cells in target organs. In the particular cas of colon cancers, although lymph node involvement is frequent, metastatic medullary involvement (while rarely at the origin of identified metastasis) can also be observed. Furthermore, micrometastatics cells can be identified in the circulating blood. This research relies on recent technics of immunocytochemistry with image analysis or molecular biology technics (generally PCR or RT-PCR). It is essential to have a specific reliable marker of metastatic cells. The prognostic value of identifying micrometastasis in organs also remains to be defined.

[Tropical sprue in an expatriate]. / Sprue tropicale chez un expatrié.

INTRODUCTION: Tropical sprue is a postinfective malabsorption syndrome that occurs in some tropical endemic areas. CASE REPORT: A 65-year-old Caucasian patient, with no significant past medical history, living in Cambodia for 10 years, presented with a 23 kg weight loss and chronic diarrhea. Clinical examination was unremarkable. Laboratory tests showed a moderate nutritional deficiency syndrome. The upper gastrointestinal endoscopy showed duodenal villous atrophy and histological analysis confirmed subtotal villous atrophy with important intraepithelial lymphocytosis. The diagnosis of tropical sprue was considered on the epidemiological, clinical and biological context, and the absence of other cause of villous atrophy. A three-month duration treatment with antibiotics, folic acid and vitamin B12 was initiated. The clinical course was favorable with disappearance of diarrhea in 15 days. One year later, the patient had resumed his usual weight, and laboratory tests and duodenal biopsies were normal. CONCLUSION: The diagnosis of tropical sprue should be systematically discussed in any malabsorption syndrome with villous atrophy in a patient living or having lived in the tropics.

Distinct alterations in mitochondrial mass and function characterize different models of apoptosis.

Recent studies have shown that reduction in mitochondrial membrane potential (delta psi m) and generation of reactive oxygen species are early events in apoptosis. In this study, we present two different models of apoptotic cell death, Chinese hamster ovary (CHO) cells treated with aphidicolin and dexamethasone-treated 2B4 T-cell hybridoma cells, which display opposing mitochondrial changes. CHO cells arrested at G1/S with aphidicolin have a progressive increase in mitochondria mass and number, assessed by flow cytometry and fluorescent microscopy with mitochondria-specific probes. The increase in mitochondrial mass was not accompanied by a gain in net cellular mitochondrial membrane potential, consistent with an accumulation of relatively depolarized mitochondria. Fluorescent microscopy demonstrated an increased content of low delta psi m mitochondria in aphidicolin-treated CHO cells, but high delta psi m mitochondria were also present and remained stable in number. Mitochondrial mass correlated with decreased clonogenicity of aphidicolin-treated CHO cells. Cycloheximide prevented both the proliferation of mitochondria and subsequent cell death. In contrast, dexamethasone treatment of 2B4 T-cell hybridoma cells caused a decrease in delta psi m without mitochondrial proliferation. Cycloheximide and Bcl-2 overexpression inhibited the loss of delta psi m, as well as apoptosis. In both models, cell death was associated with a decrease in mitochondrial potential relative to mitochondrial mass, suggesting that an accumulation of damaged or dysfunctional mitochondria had occurred.