Hong Wui Tan

Diagnosis of adenoid cystic carcinoma of the lung by bronchial brushing: a case report.

BACKGROUND A diagnosis of pulmonary adenoid cystic carcinoma on exfoliative cytology specimen is very uncommon. The diagnostic cytologic material typically is obtained following a tissue biopsy. No previous report of the diagnosis has been made on bronchial brushing cytologic material when the procedure preceded a tissue biopsy. CASE A 44-year-old man who used to smoke cigarettes and was otherwise well complained of persistent cough for the past 6 months. A chest radiograph revealed a mass lesion in the left hilum. Computed tomography of the chest disclosed an irregular and spiculated soft tissue mass in the left apical anterior segment. Bronchial brushing via bronchoscope was performed, revealing carcinoma cells consistent with an adenoid cystic carcinoma on cytology. A bronchial biopsy and subsequent left upper lobectomy were performed, confirming the diagnosis of adenoid cystic carcinoma of the lung associated with tumor extension to the epithelial surface. CONCLUSION A diagnosis of bronchial adenoid cystic carcinoma is possible on bronchial brushing. However, as a method in exfoliative cytology, the usefulness of bronchial brushing in diagnosing this tumor is limited by the neoplasms proximity to the mucosal surface and whether the mucosa has been breached.

An unusual cause of granulomatous inflammation: eosinophilic abscess in Langerhans cell histiocytosis.

Eosinophilic abscess inciting a granulomatous response has rarely been reported and appears not to have been described in the setting of a neoplasm. In this report, a case is described where a granulomatous response occurred around eosinophilic abscesses in a patient with Langerhans cell histiocytosis, an association which has not previously been documented. On histology, the excised lymph node showed the presence of eosinophilic abscess and necrosis surrounded by granulomas, which in turn were surrounded by Langerhans cells, a feature confirmed on immunohistochemistry. Although rare, this case highlights the importance of careful examination of eosinophilic abscess with granulomatous inflammation in order to exclude an underlying neoplasm.

A 43-year-old chinese man with a retro-orbital mass.

Schwannomas are infrequent intracranial tumors, comprising only 8% of all primary intracranial neoplasms. They are typically located in the cerebellopontine angle region (5). The cellular schwannoma, described by Woodruff in 1981 (8), is considered a variant of schwannoma and comprises about 10% of all schwannomas (5). The most common location of cellular schwannoma is the paravertebral region with the sacral site constituting 64% of all neoplasms (1). The intracranial location accounts for 8% of all cellular schwannomas. The retrobulbar region is an extremely uncommon site for this tumor and to the best our knowledge, our current case forms the fourth case after those described by Casadei et al (1) and Huang et al (4) Cellular schwannoma is generally encapsulated and sometimes associated with a nerve (1). On histology, unlike classical schwannoma, cellular schwannoma discloses a marked increase in cellularity, comprising fascicles of spindle cells which can occasionally be associated with a herringbone or storiform pattern. Compact and hypercellular fascicles recapitulating Antoni-A areas can be identified. Although classic Verocay bodies are seldom identified, there may be occasional suggestion of palisades (1, 2, 4, 7). Antoni-B areas are, however, not prominently featured (1). The spindle cells may exhibit mild nuclear atypia (4, 7). Thick-walled blood vessels usually displayed in classic schwannoma are also present in the cellular variant (1, 4). Microscopic areas of necrosis may be observed in cellular schwannoma, but the geographic necrosis seen in malignant peripheral nerve sheath tumor (MPNST) is absent (1, 3, 7). Mitotic activity usually does not exceed four per 10 high power fields (2–4) although in plexiform cellular schwannoma in childhood, a mitotic index of up to 31 per 10 high power fields has been reported (9). Cellular schwannoma is strongly positive for S100 protein and vimentin (1). GFAP is variably positive (1, 2, 4, 7). The striking feature seen ultrastructurally is the presence of numerous tightly packed intertwined cell processes (1) as identified in our case. Primitive intercellular junctions and cell membranes abutting stroma and covered by well-developed continuous and occasionally duplicated basement membranes, are also present. Luse bodies may be absent. In the retrobulbar region, a diagnosis of meningioma may be considered, as the tumor cells in a cellular schwannoma may form whorls (1). However, the presence of areas resembling Antoni A in association with a negative staining for EMA mitigates against a diagnosis of meningioma. Glial tumors enter the differential diagnosis given the findings of GFAP positivity within the tumor. However, careful discernment of Antoni A-like areas and ultrastructural findings on electron microscopy in conjunction with the clinical and radiological findings favor a diagnosis of cellular schwannoma in our case. Cellular schwannoma may be mistaken for MPNST because of its association with increased cellularity, nuclear atypia, mitotic activity, necrotic foci, bony erosion and tumor recurrence (1, 2, 4, 7). However, a MPNST (3) is usually more cellular, associated usually with a higher degree of anaplasia, lacks the thick walled hyalinized blood vessels and usually demonstrates only focal S-100 positivity on immunohistochemistry. In the orbital region, a solitary fibrous tumor has been confused for a schwannoma (6). While metastases and death have not been described in cellular schwannoma (1, 2, 4, 7), recurrences in incompletely resected cellular schwannoma have been documented, especially in sites where complete tumor resection is difficult to achieve (eg, intraspinal or intracranial) (1, 4). In such instances, mitotic count significantly correlates with the incidence of tumor recurrence (1) and close follow-up is advocated.

An adult with lung nodules and renal mass: diagnosis on cytology Part 1

CASE REPORT A 64-year-old Chinese man presented with cough and haemoptysis over 2 months. Chest X-ray revealed multiple nodules in both lungs associated with a right pleural effusion, a finding confirmed on thorax computed tomography (CT) scan. In addition, mediastinal lymphadenopathy and multiple pleural nodules were noted on CT scan. CT scan of the abdomen revealed a right renal mass measuring 8.4 cm in the upper pole. Following a negative diagnosis for malignancy on a series of investigations, a CT guided fine needle aspiration (FNA) biopsy of the lung was performed. Due to relative ease in obtaining a tissue sample, aspiration of a right pleural based mass was performed using a 22 gauge needle which was followed by a core tissue biopsy. Four alcohol-fixed smears stained with Papanicolaou (Pap) and four air-dried smears stained with Diff Quik (DQ) showed low to moderate cellularity. There were clusters of polygonal cells with abundant pale vacuolated cytoplasm (Fig. 1), discernible nucleoli and generally low nuclear to cytoplasmic ratios (Fig. 2). There were some clusters associated with a branching vascular network (Fig. 3). The background revealed fibrinous material. The tissue biopsy consisted of five cores of tissue measuring from 0.2 to 0.7 cm in length. These were fixed in buffered formalin and processed for routine histology.