Role of a pattern-based approach in interpretation of transbronchoscopic lung biopsy and its clinical implications.

Background. Transbronchial lung biopsy (TBLB) is commonly performed for confirming the tissue diagnosis of diffuse parenchymal lung diseases (DPLDs). There is an urgent need to establish guidelines for interpretation of TBLB in order to improve its diagnostic utility. Methods. We retrospectively studied 916 consecutive patients (494 males; mean age 49 years) who underwent TBLB over a 5-year period (July 2005 to July 2010) at Vallabhbhai Patel Chest Institute. Results. In 615 (67.1%) procedures, material obtained during TBLB was adequate for histopathology interpretation. Pathological features evaluated in each case were: alveolar architecture, inflammatory infiltrate, interstitial fibrosis, atypical cells, pigment deposition, honey-comb change and fibroblast foci. The cases were categorised on the basis of histopathology into six patterns: (1) adequate biopsy without a specific diagnostic abnormality (n=137, 22.3%); (2) acute pneumonitis (n=29, 4.7%); (3) neoplasia (n=109, 17.7%); (4) chronic interstitial inflammation with or without fibrosis (n=138, 22.4%); (5) granulomatous inflammation, (n=186, 30.2%); and (6) other specific causes (n=16, 2.6%). Definitive diagnosis could be made after correlation of TBLB histopathology with clinical and radiological features in 55.3% cases. Conclusions. TBLB appears to be an important diagnostic tool for the diagnosis of DPLDs. The use of a pattern-based approach to TBLB adds to its diagnostic yield and can be helpful in cases where open lung biopsy is not available.

Immunohistochemical staining on fine needle aspiration biopsy-cell block specimens in the differential diagnosis of lung cancers.

BACKGROUND: Fine needle aspiration biopsy [FNAB] is used extensively in the clinical work-up of radiologically detected lung lesions. However, categorisation of lung cancer by computed tomography guided FNAB alone is limited by overlapping morphological features. AIM: To examine further the utility of immunohistochemical panel of antibodies to thyroid transcription factor [TTF-1], synaptophysin, chromogranin A [CgA], cytokeratin-pan, cytokeratin-7 [CK-7], cytokeratin-20 [CK-20], leucocyte common antigen [LCA], and carcinoembryonic antigen [CEA] in cytologic cell block samples in the differential diagnosis of lung cancer. METHODS: Twenty-nine FNABs of newly diagnosed cases of lung cancer were studied. Immunohistochemistry was done on paraffin embedded cell block sections using Dako monoclonal antibodies. RESULTS: Morphological diagnosis of non-small cell carcinoma (NSCLC) was made in 22/29 [76%] and small cell carcinoma in 7/29 (24%) cases. Five of the seven (71.4%) cases of small cell carcinoma were CgA+/TTF-1+, 14.3% [1/7] were CgA+/ synaptophysin+/TTF-1-negative. In one case, LCA positivity lead to the diagnosis of non-Hodgkins lymphoma. The NSCLC was categorised further into well differentiated 11/22 [50%], moderately differentiated 7/22 [31.8%] and poorly differentiated 4/22 [18.2%] cases. Cytokeratin-pan positivity in squamous cell carcinomas [n=15] was seen to be related to cellular differentiation. All the three cases of adenocarcinoma were CK-7+/CK-20 negative. In one case with large cell carcinoma, CgA-positivity lead to recategorisation as large cell neuroendocrine carcinoma. CONCLUSIONS: Our results suggest that the proposed panel of immunohistochemical markers might help further classification of lung carcinomas even in small FNAB material and permit more consistent patient enrollment for trials with targeted treatments.

Time course of pulmonary pathology, cytokine influx and their correlation on augmentation of antigen challenge by influenza A virus infection.

A murine model of influenza A virus exacerbation of allergen induced airway inflammation, pulmonary histopathological changes, bronchoalveolar lavage fluid (BALF) analysis, cytokine influx and the time course of these events have been studied. The present study was undertaken to determine the relative contributions of Thl/Th2 cytokines to the histopathological changes in the lungs observed at 9, 12, 24 and 48 hr following antigen challenge in mice previously immunized with influenza A virus. BALF analysis of acute phase group revealed statistically significant increase in neutrophils at 9 hr, macrophages at 12 hr, lymphocytes and eosinophils at 24 hr, as compared to OVA-sensitized control mice. These changes were associated with an alteration in the levels of IL-4, IL-5 and IFN-gamma. A peak of IL-4 at 24 hr significantly enhanced bronchiolar and perivascular histopathology, whereas increased IL-5 level peaking at 24 hr was correlated with the enhanced infiltration of eosinophils in both BALF and lung tissue. There was simultaneous depletion of IL-10 an anti-inflammatory cytokine leading to persistence of pulmonary inflammation in case of acute phase group. Histopathology at 24 and 48 hr showed severe denudation of bronchiolar lining epithelium surrounded by dense chronic inflammatory infiltrate. Chronic interstitial infiltrate with focal loss of architecture, marked oedema, extravasation of RBCs from congested blood vessels and laying down of reticulin fibres was observed in acute phase. Thus, infection with influenza A virus on pre-existing asthmatic immunopathology elicits a cascade of Th2 cytokines with influx of inflammatory cells in BALF, mucosal and interstitial inflammation leading to asthma exacerbations.

Botryoid rhabdomyosarcoma of mesentery--a case report.

Botryoid rhabdodmyosarcomas are described predominantly in hollow visceral organs. We present case of an embryonal (botryoid) rhabdomyosarcoma arising in mesentery of a two year old male child.

Massive ovarian edema with contralateral mature cystic teratoma--a case report of an uncommon combination.

A case with massive ovarian edema (MOE) of left ovary--a rare pseudotumour and mature cystic teratoma of right ovary is described in a young unmarried girl of 16 years. The etiopathological concepts, morphological changes and differential diagnosis are described. Knowledge about the entity and its existence are important for correct treatment. This is the first reported case from Nepal.

Massive cystic degeneration of a uterine leiomyoma presenting as an ovarian cyst: a case report.

An unusual case of massive cystic degeneration in an uterine leiomyoma measuring 21 cm in diameter, in a 40 year old female is being presented. It was diagnosed as a cystic adnexal tumor on ultrasonogram. Interlacing bundles of smooth muscle were identified in the cyst wall, which was confirmed on special stains. The differential diagnoses considered in this case are discussed. To the best of our knowledge, this is the largest cystic degeneration in an uterine leiomyoma reported in the literature.