Lymphomas of the mediastinum

Abnormal Presentation and Challenging Diagnosis of Mediastinal Lymphoma: A Case Report

We describe a rare case of classical Hodgkin lymphoma (HL) in a 20-year-old female patient. She presented to our hospital with chest wall swelling after months of post-chest trauma management. The swelling was initially treated as an infected hematoma, and the patient was referred for surgical evacuation. During the surgery, the swelling was found to be a mass that extended to the mediastinum. A biopsy was taken, which later resulted in the diagnosis of a granular cell tumor (GCT). A decision on surgical resection by video-assisted thoracoscopic surgery (VATS) was taken after discussion with the multidisciplinary team of surgery, cardiothoracic surgery, oncology, pathology, and radiology. During the surgery, a frozen section biopsy was taken, which showed no features of lymphoma or granular cell tumors. The surgery was followed by a midline sternotomy to control the bleeding from an accidentally injured major vessel. The bleeding was controlled, and the mass was dissected and sent for histopathological examination. The histopathology showed nodular classical HL features, and the patient was referred for chemotherapy. In our case, the patient was initially diagnosed with GCT, but with complete resection and an adequate biopsy, the mass was found to be a classical HL. Possible cross-cellularity is questioned, and the possible correlation between the two findings encouraged us to report this case.

Fine-needle aspiration of the mediastinum: a clinical, radiologic, cytologic, and histologic study of 42 cases

Forty-two fine-needle aspirates (FNA) of the mediastinum were reviewed from 1984-1995. The clinical, radiologic, pathologic, and cytologic material was studied. Twenty-five males and 17 females had an age range from 10-72 yr and a mean of 41 yr. Common complaints were chest pain, dyspnea, and cough. Thirty-eight tumors were in the anterior/superior mediastinum. Fifty-seven percent were primary neoplasms (Hodgkin's lymphoma, 7; non-Hodgkin's lymphoma, 6; thymoma, 3; germ-cell tumor, 3; thymic carcinoid and angiosarcoma, 1 each; and malignant not otherwise specified, 3). Twenty-four percent were metastatic tumors (carcinoma, 9; and sarcoma, 1). Twelve percent were benign conditions (granulomatous disease, 2; multinodular goiter, 1; extramedullary hematopoesis, 1; and one thymic cyst). Seven percent were inconclusive. FNA yielded adequate tissue for diagnosis in 83% and a correct diagnosis in 86%. There was one false-negative and no false-positive diagnosis. FNA is a useful tool for accurate tissue diagnosis of mediastinal masses.

[Mediastinal non-Hodgkin's lymphoma: atypical presentation diagnosed with bronchoscopy]

Primary mediastinal non-Hodgkin lymphoma is a rare entity that can manifests with secondary pulmonary involvement. The case of a 37 years-old man patient with non-Hodgkin lymphoma mixed B-cell, which was diagnosed by means of bronchoscopic biopsy, is presented. His characteristics clinical and radiologic presentation, and diagnostic usefulness of fiberoptic bronchoscopy, is remarked. We revised clinical and pathologic features of interests for this lymphoproliferative disorders with thoracic involvement.

A comparison of distinct modes of tumor cell death in Hodgkin's disease using morphology and in situ DNA fragmentation

The study examined the morphology and frequency of cell death occurring spontaneously in lymph nodes from patients with Hodgkin's disease. In addition to necrosis, which was infrequent and usually in patches, we document two cell types showing features of individual cell death: mummy cells end apoptotic cells. Mummy cells present no evidence of DNA fragmentation, but show electron microscopic features of "dark cells." Apoptotic Hodgkin-Reed-Sternberg cells are found frequently and are easier to demonstrate by in situ and labeling of fragmented DNA than by light microscopy only. In many cases phagocytosis of apoptotic cells is also documented. The significance of these findings to the limited number of Hodgkin-Reed-Sternberg cells in most cases of Hodgkin's disease is discussed.

Apoptosis overview emphasizing the role of oxidative stress, DNA damage and signal-transduction pathways

Apoptosis (programmed cell death) is a central protective response to excess oxidative damage (especially DNA damage), and is also essential to embryogenesis, morphogenesis and normal immune function. An understanding of the cellular events leading to apoptosis is important for the design of new chemotherapeutic agents directed against the types of leukemias and lymphomas that are resistant to currently used chemotherapeutic protocols. We present here a review of the characteristic features of apoptosis, the cell types and situations in which it occurs, the types of oxidative stress that induce apoptosis, the signal-transduction pathways that either induce or prevent apoptosis, the biologic significance of apoptosis, the role of apoptosis in cancer, and an evaluation of the methodologies used to identify apoptotic cells. Two accompanying articles, demonstrating classic apoptosis and non-classic apoptosis in the same Epstein-Barr virus-transformed lymphoid cell line, are used to illustrate the value of employing multiple criteria to determine the type of cell death occurring in a given experimental system. Aspects of apoptosis and programmed cell death that are not covered in this review include histochemistry, details of cell deletion processes in the sculpting of tissues and organs in embryogenesis and morphogenesis, and the specific pathways leading to apoptosis in specific cell types. The readers should refer to the excellent books and reviews on the morphology, biochemistry and molecular biology of apoptosis already published on these topics. Emphasis is placed, in this review, on a proposed common pathway of apoptosis that may be relevant to all cell types.

Scanning and transmission electron microscopy of clonal peripheral blood lymphocytes in low grade non-Hodgkin's B-cell lymphomas with predominant splenomegaly

Peripheral blood mononuclear cells (PBLs) from 14 patients with low grade non-Hodgkin's B-cell lymphomas with predominant splenomegaly were studied by means of scanning (SEM) and transmission electron microscopy (TEM). All patients had peripheral blood and bone marrow involvement, the absence of lymphoadenopathy, and, except in one case, immunophenotypic features of a malignant proliferation of mature spleen B-cells arising from outside the germinal center, but not consistent with CLL or HCL. Several distinctive cytological features were observed in PBLs of the different subgroups. The SEM surface features of PBLs in patients with intermediate differentiation lymphocytic lymphoma (IDL) (five cases), lymphoplasmacytoid immunocytoma (LP-IC) (two cases), and mixed small and large cells malignant lymphoma (one case) were characterized by the presence of numerous well-developed microvilli. Some distinctive TEM ultrastructural features were also seen in the different cases. In the two cases of splenic lymphoma with villous lymphocytes (SLVL), SEM revealed large and elongated surface microvilli generally arising from two or three poles of the cells. This surface morphology, confirmed by TEM analysis, may be pathognomonic of this disease. Four additional cases, tentatively classified as small lymphocytic lymphoma on the basis of immunophenotypic data, were extremely heterogeneous at both SEM and TEM analysis. The ultrastructural features revealed by SEM and TEM may be useful for the more precise characterization of this heterogeneous group of diseases, which is generally difficult to define even when immunophenotypic and molecular approaches are used.

Electron microscopy what Izzits revisited: an ultrapath VI quiz

Thirteen cases of various natures, selected from a collection shown and discussed at Ultrapath VI, are presented in quiz format for recognition or diagnosis.