Search

Introduction: There is increasing need for more testing in non-small cell lung cancer given the introduction of newer targeted therapies. Cytological specimens including conventional smears (CS), cell blocks (CB), and liquid-based cytology (LBC) are an alternative to histologic tissue (HT) specimens in detecting EGFR mutations, but the concordance of these 2 specimens is yet to be determined. The aim of the present systematic review is to determine the concordance rates between different cytologic specimens with HT in detecting EGFR mutations. Methods: PubMed, Cochrane Library, and Google Scholar were utilized in the primary search, along with reference lists of electronically retrieved full-text articles. Concordance rates were pooled together if 2 or more studies reporting the same type of cytologic specimen were available. Results: Overall, 15 studies were included in this review, with 13 studies included in the pooled analysis. There was an overall concordance rate of 92.8% in 593 paired cytologic and HT specimens, with LBC having the highest concordance rate of 96.0%, followed by CS and CB, each with a concordance rate of 95.8%, although the concordance rate of CS and/or CB was lower at 90.6% with a larger pool of studies. LBC was found to have a significantly higher concordance rate than CS and/or CB. Conclusion: Cytological specimens have a high concordance rate in detecting EGFR mutations, when compared to HT. LBC has shown superior concordance rates compared to CS and CB. Cytological specimens should be considered as an additional and alternative source of diagnostic material for EGFR testing.

Background: Malignant transformation of heterotopic pancreatic tissue is a rare entity with only several case reports published in the scientific literature. Adjuvant chemotherapy following oncological resection for lesions with nodal metastasis has not been well described and there are no guidelines available to guide the management of these patients. Case Presentation: We present a case of gastric heterotopic pancreatic carcinoma with nodal metastasis in a young patient with breast cancer gene (BRCA) 2 mutation. He had undergone a laparoscopic wedge resection for a gastric lesion initially thought to be a gastrointestinal stroma tumor. Given the involvement of the wedge resection margins, the patient underwent a distal gastrectomy with oncological lymph nodal clearance. One out of the 33 harvested lymph nodes harboured micrometastasis while the main gastrectomy specimen did not have any residual malignancy. Following the histological diagnosis, he received an adjuvant chemotherapy regime akin to that prescribed for locally advanced pancreatic adenocarcinoma with good response. This is, to our knowledge, also the first such case report in a patient with BRCA2 mutation. Conclusions: Pre-operative diagnostic confirmation is challenging and endoscopic procedures pose significant false negatives. Reports of nodal metastasis following oncological resection are limited and there are no guidelines regarding adjuvant therapies. We would recommend a chemotherapy regimen similar to that for primary locally advanced pancreatic carcinoma in patients found to have nodal metastasis.

Introduction The current gold standard for diagnosing interstitial lung disease (ILD) involves an ILD clinic evaluation, followed by discussion in a multidisciplinary meeting (MDM). However, there is a paucity of data on the impact of ILD MDMs on the diagnosis and management of ILDs in Southeast Asia. We studied the clinical impact of the ILD service on the diagnosis and management of ILDs at a university-affiliated tertiary hospital in Singapore. Methods A single-centre retrospective review was done on 97 consecutive patients referred for evaluation to the ILD service from March 2016 to August 2017. Results Mean age of the patients was 67 ± 11 years. Gender distribution was almost equal (52% male), with a majority of never-smokers (63%). Mean forced vital capacity (FVC) was 1.81 ± 0.66 L (66% ± 20% predicted). The three commonest referral diagnoses were ILD of uncertain classification (n = 38, 39%), connective tissue disease-associated ILD (CTD-ILD) (n = 24, 25%) and idiopathic pulmonary fibrosis (IPF) (n = 16, 17%). Following evaluation by the ILD service, there was a change of diagnosis in 60 (62%) patients and a change of management in 71 (73%) patients. The majority of consensus MDM diagnoses were IPF (n = 35, 36%), CTD-ILD (n = 30, 30%) and others (n = 15, 15%). There was a significant prognostic separation between the IPF and non-IPF diagnoses made following evaluation by the ILD service. Conclusion The ILD service allowed for more precise subtyping of various ILDs. This is particularly useful for IPF patients, who can benefit from antifibrotic therapies.

Perivascular epithelioid cell (PEC) tumors are rare tumors of mesenchymal origin and can affect many anatomic regions. Although these tumors are usually benign, malignant variants exist. We document for the first time a malignant PEComa arising from the pleura of a 43-year-old Malay woman. The pathology of the tumor as well as differential diagnoses is discussed.

Carbohydrate antigen 19–9 (CA 19–9) is a tumor marker widely accepted as the most useful blood test in diagnosing and monitoring pancreatic cancer. However, CA 19–9 may also be raised in other conditions such as colorectal, hepatic, lung, and ovarian carcinoma as well as benign conditions such as hepatobiliary and pulmonary diseases. CA 19–9 is rarely elevated above 200 U/ml in benign conditions with values exceeding 1000 U/ml being highly suggestive of malignancy. The mechanism of secretion in both malignant and benign conditions remains unclear. Desmoplastic fibroblastoma (DF) is a benign soft tissue tumor. CA 19–9 has not been reported in association with DF previously. We present a case of raised serum CA 19–9 in a 71-year-old male attributed solely to DF in his left cubital fossa. The patient’s CA 19–9 level rose from 56 U/ml at the time of presentation to 3763.8 U/ml over a period of 9 months. Post-DF excision, the CA 19–9 level decreased to 1464 U/ml at 1 month, 162.3 U/ml at 2.5 months, and 24U/ml, within normal range, at 7 months post-surgery. CA 19–9 levels continued to remain at 24 U/ml 1.5 years post-tumor excision. The CA 19–9 level in this patient was highly elevated which is unusual in association with a benign tumor. The rate of decrease in CA 19–9 level post-excision was in keeping with that reported after pancreatic cancer resections. This is the first case of DF in association with raised CA 19–9.

Context Literature suggests that oncogenic osteomalacia is usually caused by a benign mesenchymal tumor secreting fibroblast growth factor subtype-23 (FGF-23), but the involvement of other phosphatonins has only been scarcely reported. We have previously published a seemingly typical case of oncogenic osteomalacia. Following curative neoplasm resection, we now report unique molecular characteristics and biology of this tumor. Case Description A 25-year-old man had been diagnosed with severe oncogenic osteomalacia that gradually crippled him over 6 years. 68Ga-DOTA-TATE positron emission tomography/computed tomography scan localized the culprit tumor to his left sole, which on resection revealed a deep fibrous histiocytoma displaying a proliferation of spindle cells with storiform pattern associated with multinucleated giant cells resembling osteoclasts. Circulating FGF-23, which was elevated more than 2-fold, declined to undetectable levels 24 h after surgery. Microarray analysis revealed increased tumor gene expression of the phosphatonins FGF-23, matrix extracellular phosphoglycoprotein (MEPE) and secreted frizzled-related protein subtype 4, with elevated levels of all 3 proteins confirmed through immunoblot analysis. Differential expression of genes involved in bone formation and bone mineralization were further identified. The patient made an astonishing recovery from being wheelchair bound to fully self-ambulant 2 months postoperatively. Conclusion This report describes oncogenic osteomalacia due to a deep fibrous histiocytoma, which coincidentally has been found to induce profound muscle weakness via the overexpression of 3 phosphatonins, which resolved fully upon radical resection of the tumor. Additionally, genes involved in bone formation and bone remodeling contribute to the molecular signature of oncogenic osteomalacia.

Gangliogliomas comprise of less than 1% of all primary brain tumours. Malignant transformation is rare. Correspondingly, secondary gliosarcomas, especially in the absence of previous irradiation exposure is too, exceedingly rare. Recent evidence supports the use of mutant IDH1 testing in suspected adult gangliogliomas as a distinguishing feature between ganglioglioma and early diffuse astrocytoma. The authors report a case of a ganglioglioma (WHO I) in the cingulate gyrus that underwent malignant transformation and propagated into a multi-lesional gliosarcoma (WHO IV glioblastoma variant). A previously well 59-year-old lady presented with first-onset focal seizures secondary to a left cingulate gyrus lesion. Stereotactic biopsy of the lesion demonstrated an IDH1 (R132H) ganglioglioma. The patient remained well until a routine follow-up MRI performed 36 months later showed significant progression of the initial lesion and a new, separate lesion in the left temporoparietal lobe. Surgical excision was performed. The final histology reported a gliosarcoma. In view of the unusual findings, the case is reviewed corroboratively with current disease understanding. Keywords: Ganglioglioma, Gliosarcoma, Isocitrate dehydrogenase 1

Neoplasms arising from the diaphragm are not typically seen in clinical practice, though they may inflict significant morbidity and mortality. In the realm of thoracic surgery, osteochondromas are only encountered at the thoracic wall or vertebra. In this study, we describe a case of an osteochondroma arising from the diaphragm masquerading as a malignant lesion. The tumor was resected via robotic-assisted means and the patient was discharged with no complications.

Described in Japan by Amitani et al in 1992, the entity of idiopathic upper lobe fibrosis was subsequently given the name pleuroparenchymal fibroelastosis (PPFE) in the English-speaking world. Pleuroparenchymal fibroelastosis is believed to be a rare disease characterized by a fibrosing process affecting the pleura and the subpleural lung parenchyma, with a predilection for the upper lobes. Uniquely, the fibrosing process is elastotic in nature, being associated with intra-alveolar fibrosis. The etiology of PPFE is unclear at this juncture, with many cases being considered as idiopathic forms of the disease. Conditions associated with PPFE include infections, bone marrow transplantation, and autoimmunity. In this review, we explore the clinical, radiologic, and pathologic features associated with PPFE in light of current understanding of the disease. Recent studies implicated that PPFE may not be as uncommon as claimed. The various differential diagnoses and implications of diagnosing PPFE are discussed.

The vast majority of intraspinal meningiomas occur in an intradural extramedullary location. A meningioma in a purely extradural location in the cervical spine as reported here is quite exceptional. Extradural meningiomas tend to show more aggressive features than intradural meningiomas and are often confused with malignant neoplasms. We report an invasive extradural meningioma in the cervical spine with multi-segmental involvement, extension through the neural foramina and encasement of the subjacent vertebral artery, mimicking malignancies such as lymphoma and sarcoma. Although rare, meningiomas may demonstrate extradural multi-segmental growth and should be considered in the differential diagnosis of such lesions.

Second lymphoid neoplasms are an uncommon but recognized feature of non-Hodgkin’s lymphomas, putatively arising secondary to common genetic or environmental risk factors. Previous limited evaluations of clonal relatedness between successive mature B-cell malignancies have yielded mixed results. We describe the case of a man with intravascular large B-cell lymphoma involving the central nervous system who went into clinical remission following immunochemotherapy and brain radiation, only to relapse 2 years later with a plasmacytoma of bone causing cauda equina syndrome. The plasmacytoma stained strongly for the cell cycle regulator cyclin D1 on immunohistochemistry, while the original intravascular large cell lymphoma was negative, a disparity providing no support for clonal identity between the 2 neoplasms. Continued efforts atcataloging and evaluating unique associations of B-cell malignancies are critical to improving understanding of overarching disease biology in B-cell malignancies.

The pancreas is an unusual site for tumor metastasis, accounting for only 2% to 5% of all malignancies affecting the pancreas. The more common metastases affecting the pancreas include renal cell carcinomas, melanomas, colorectal carcinomas, breast carcinomas, and sarcomas. Although pancreatic involvement by nonrenal malignancies indicates widespread systemic disease, metastatic renal cell carcinoma to the pancreas often represents an isolated event and is thus amenable to surgical resection, which is associated with long-term survival. As such, it is important to accurately diagnose pancreatic involvement by metastatic renal cell carcinoma on histology, especially given that renal cell carcinoma metastasis may manifest more than a decade after its initial presentation and diagnosis. In this review, we discuss the clinicopathologic findings of isolated renal cell carcinoma metastases of the pancreas, with special emphasis on separating metastatic renal cell carcinoma and its various differential diagnoses in the pancreas.

There is evidence that aspirin and non-aspirin non-steroidal anti-inflammatory drug (NSAID) have anti-carcinogenic properties, but their effect on lung cancer, in particular in never-smokers, is unclear. Information on past or current use of anti-inflammatory medication was obtained in 398 Chinese female primary lung cancer cases and 814 controls in a hospital-based study in Singapore. 65% of cases and 88% of controls were never-smokers. Controls were excluded if they had been admitted for conditions associated with aspirin or NSAID use (n=174). Regular aspirin use (twice a week or more, for a month or more) was associated with a reduced risk of lung cancer (adjusted odds ratio [OR] 0.50, 95% confidence intervals [95%CI] 0.31-0.81 in non-smokers; OR 0.38, 95%CI 0.16-0.93 in smokers). Regular use of non-aspirin NSAID, paracetamol, steroid creams and steroid pills was uncommon and no association with lung cancer was detected. Our results suggest that aspirin consumption may reduce lung cancer risk in Asian women and are consistent with current understanding of the role of cyclooxygenase in lung carcinogenesis.

The authors examined relations between reproductive factors and 5 estrogen pathway gene polymorphisms (CYP17 rs743572, CYP19A1 rs10046, ERβ rs1256049, ERβ rs4986938, and COMT rs4680) among 702 Singapore Chinese female lung cancer cases and 1,578 hospital controls, of whom 433 cases (61.7%) and 1,375 controls (87.1%) were never smokers. Parity (per child, odds ratio (OR) = 0.92, 95% confidence interval (CI): 0.87, 0.97) and menstrual cycle length (for ≥30 days vs.

Chondroblastomas are rare bone tumors, accounting for less than 2% of all bone tumors. Although generally benign, there are instances of aggressive tumor behavior with extensive soft tissue invasion and even metastasis. In this report, we detail an instance where the tumor displayed extensive soft tissue invasion. As there is tumor heterogeneity in terms of morphologic appearance as well as a varied immunohistochemistry profile, a diagnosis of chondroblastoma may not be straightforward if the initial biopsy sample did not include the more characteristic area. In our case, the tumor expressed cytokeratin, calponin, and p63 in addition to S-100, potentially raising a diagnosis of a mixed tumor. The differential diagnosis and biologic behavior of chondroblastomas are discussed.

Intramuscular haemangiomas are benign soft-tissue tumours, commonly located in the extremities. We present a right-leg intramuscular haemangioma with florid periosteal reaction in adjacent tibia, mimicking a primary bone tumour. Plain radiograph and magnetic resonance imaging features are illustrated with the surgical and histopathological findings. Radiologists need to be familiar with reactive bone changes secondary to deep-seated intramuscular haemangiomas to avoid potential misdiagnosis.

Solitary fibrous tumor was initially thought to be a pleura-based tumor. However, over the last two decades, its involvement in a variety of extrapleural sites gained recognition. Nonetheless, a primary involvement of the endocrine organs is rare, and in this report, we detail an instance where the tumor affected the adrenal gland of a 71-year-old Arab man. On histology, besides the typical morphologic features seen in solitary fibrous tumor, the neoplasm also exhibited unusual features on immunohistochemistry such as positive staining for cytokeratin AE1/3 and calponin in conjunction with diffuse expression for S-100. The genetic tests for t(X:18) as seen in synovial sarcoma were negative, and the overall histological appearance favored a diagnosis of solitary fibrous tumor. To the best of our knowledge, this report represents the fifth case of a solitary fibrous tumor primarily occurring in the adrenal gland. The differential diagnoses of this neoplasm in our case and a brief summary of solitary fibrous tumor primarily involving the various endocrine organs are presented.

Introduction Epidermal growth factor receptor (EGFR) mutations are more common in lung adenocarcinoma and in female patients of East-Asian origin. We aimed to assess the expression of female hormone receptors in East-Asian lung adenocarcinomas, their correlation with EGFR mutations, and prognostic significance. Methods Estrogen receptor (ER)±, ER², progesterone receptor (PR), and Her-2 expression were examined using immunohistochemical methods on 109 lung adenocarcinoma cases. EGFR mutations were analyzed by partially denaturing high performance liquid chromatography. Association of hormone receptor with clinical factors was assessed using the Fisher's exact test. Associations with survival were assessed using the Cox proportional hazard model. Results Using scoring criteria routinely used for breast cancer, there were four (4%) ER±, one (1%) ER², six (6%) PR, and one (1%) Her-2 positive cases. Considering any staining as positive, 14 (14%) ER±, 10 (9%) ER², 12 (12%) PR, and 26 (24%) Her-2 cases were positive. Thirty-nine patients (39%) had EGFR mutations. ER± positivity was significantly associated with ER² and PR positivity. There were more EGFR mutations seen in tumors with ERs positivity (60%) compared with those with negative expression (37.9%), and there was a trend toward a poorer outcome for patients with tumor that were positive for ERs and Her-2. Conclusions We found that ER±, ER², PR, and Her-2 expression in lung adenocarcinoma are present but limited. This suggests that hormonal influence may not be an important factor to account for the high prevalence of lung cancer among the East-Asian women.

in our case, biopsies do not always yield the expected results. We should not forget that this test may also sometimes give false positive results, especially in low-grade AS that cannot be readily distinguished from radiotherapy-induced changes [3]. Standard therapy entails surgery with complete tumour resection. However, as in our case, chemotherapy becomes the first treatment of choice when surgery is not possible. Results are far from alone promising for the most widely used drugs. Anthracyclines alone or with iphosphamide have led to disease control after several months (between 7 and 24 months) [8], always in combination with previous surgery. Over the past few years, paclitaxel has been used for used in advanced stage and/or metastatic AS [9,10]. In our case, the weekly taxane kept the disease under control for five months. Our case reveals the sound profile of paclitaxel as a single agent in the initial treatment of unresectable, radiotherapyinduced AS in an anthracycline-naive patient.

Plasmablastic lymphoma is a rare variant of a diffuse, large B-cell lymphoma, which typically presents in the oral cavity in immunocompromised patients. In HIV positive patients, this tumor has a tendency to manifest in extramedullary sites. In this report, we document a rare instance in which this neoplasm besides affecting the bone marrow also involved the lung. In addition, the lymphoma in our case disclosed CD10 positivity on immunohistochemistry and t(8;14)(q24;q34) translocation on cytogenetic analysis, mimicking a Burkitt/atypical Burkitt lymphoma. The problems in diagnosis are discussed.

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 neoplasm's proximity to the mucosal surface and whether the mucosa has been breached.

Background: Anaplastic thyroid carcinoma (ATC) is one of the most aggressive human malignan- cies with a mean survival time of 6 months regardless of treatment. Aim: To present a case of lo- cally advanced anaplastic thyroid carcinoma with long-term survival. A 10-year literature review of locally advanced ATC with long-term survival (more than 2 years) is also presented. Case pres- entation: We present a case of locally advanced anaplastic thyroid carcinoma (ATC) with tracheal invasion in a 67-year-old elderly Chinese man who was treated with radical surgery encompassing total thyroidectomy, neck dissection and tracheal resection followed by adjuvant radiotherapy. Long-term disease-free survival is more than 7 years to date. Conclusion: The prognosis of ATC remains poor as it is characterized by aggressive and extensive disease at presentation, the inabil- ity in most patients to perform radical enough surgery in order to achieve clear margins, high morbidity of complete extirpation and limited response to radiotherapy or chemotherapy. How- ever, if complete surgical resection is possible, patients should be treated aggressively with a combination of surgery and adjuvant radiotherapy.

Although appearance of conventional uterine endometrial stromal sarcoma is easily recognized on histology, it may uncommonly assume unusual appearances such as uterine tumor resembling ovarian sex-cord tumor, thereby hindering its diagnosis. Recently, its manifestation as an epithelioid neoplasm was described. In this report, we detail yet another instance where this tumor adopted an epithelioid morphology, presenting itself as a polyp extruding from the cervical os in a 41-year-old Chinese woman. Both the polypectomy and subsequent hysterectomy specimens revealed a predominant proliferation of CD10-negative, caldesmon-negative, and CD117-positive epithelioid cells set within a stroma containing vascular proliferation resembling endometrial stromal tumor. Areas of typical low-grade endometrial stromal sarcoma containing spindle cells that were focally positive for CD10 and negative for CD117 were present in close association with the epithelioid areas. The differential diagnoses and possible implication of CD117 positivity are discussed.

The association of membranous glomerulonephritis with benign tumors is rarely described. This report represents, to the best of our knowledge, the first documented account of the simultaneous occurrence of juxtaglomerular cell tumor of the kidney and membranous glomerulonephritis. A young Chinese woman presented with hypertension and proteinuria, whereupon investigations disclosed a renal tumor. She underwent surgical resection, and histologic examination of the tumor revealed CD34-positive uniform polygonal cells with accompanying mast cells, disposed in sheets with focal papillary pattern punctuated by cytokeratin-positive tubular structures. Characteristic rhomboid crystalline granules were identified ultrastructurally. The kidney adjacent to the tumor showed features of membranous glomerulonephritis and hypertensive arteriopathy. Proteinuria improved following tumor resection, but the patient had persistent hypertension attributable to renal hypertensive arteriopathy. This report also highlights the recently described observation of CD34 positivity in juxtaglomerular cell tumors.

BACKGROUND: No previous report of metastasizing mixed tumor (pleomorphic adenoma) of the external auditory canal (EAC) has been described. CASE: A 12-year-old, Chinese girl with a history of mixed tumor of the EAC presented with a locally recurrent, aggressive tumor and metastases to the lung and bone five years later. The primary, locally recurrent and metastatic lung tumor showed epithelial and myoepithelial elements with duct formation, chondromyxoid stroma and mitotic activity in the cellular areas on histology. Fine needle aspiration cytology (FNAC) disclosed the presence of spindle cells blending into chondromyxoidfibrillar ground substance in the recurrent and metastatic lung tumors. CONCLUSION: In primary mixed tumor of the EAC, FNAC plays a useful role in the diagnosis of recurrent and metastatic disease. Its ability to identify ominous features, such as increased mitoses in this case, may be limited by sampling. Since cytology and histology cannot reliably prognosticate, long-term follow up of mixed tumor of the EAC after complete excision is advocated.

Background While the intraoperative smear cytology of oligodendroglioma is well documented, the cytologic features of anaplastic oligodendroglioma have been described rarely. Case A 41-year-old man with a previous history of a brain tumor five years earlier presented with recurrent neurologic symptoms. Radiologic examination revealed a predominantly cystic tumor with solid areas and calcifications arising from the left temporal lobe. Intraoperative smears of the tumor were hypercellular, disclosing loosely cohesive and single cells resembling oligodendrocytes with mitotic activity and moderate anisonucleosis. The background displayed a characteristic vacuolated appearance. Tissue submitted for frozen section showed a tumor with an infiltrative margin with areas of perineuronal satellitosis. Conclusion A diagnosis of anaplastic oligodendroglioma can be made intraoperatively with the aid of smear cytology in conjunction with frozen section, assisting intraoperative management.

Primary cutaneous lymphomas rarely present to the hand surgeon. Diagnosis of primary cutaneous lymphoma in the upper extremity can be difficult to make, as they are rare, and may be mistaken for other lesions. We report an unusual case of primary cutaneous lymphoma presenting in the upper extremity. This rare differential should be considered when encountered with a lump of similar appearance in the upper extremity.

(2002). An intraventricular brain tumour in a young woman. Pathology: Vol. 34, No. 2, pp. 185-188.

A case of primitive neuroectodermal tumour (PNET) co-existing with endometrial adenocarcinoma of the uterus is reported in a 48-year-old female. Histologically, the neoplastic cells formed neuroectodermal rosettes and displayed ependymal differentiation. Focal positive immunohistochemical staining for synaptophysin, chromogranin A, CD57 and cytokeratins was noted. Merging imperceptibly with the neuroectodermal component were areas of endometrial adenocarcinoma and, to the best of our knowledge, this report represents the second case of a uterine PNET with an admixed müllerian component. The patient was disease-free 6 months following surgical resection of the tumour. The literature on this uncommon entity is critically reviewed and the histogenesis, differential diagnoses and cytomorphological features of PNET are also discussed.

Originally described in the pleura, solitary fibrous tumour (SFT) is now reported in a variety of extrapleural sites. However, description of SFT in the deep soft tissue of the neck is very rare. In this report, we document the neoplasm, deep to the right platsyma muscle but superficial to the deep fascia just above the clavicle, in an otherwise well 50-year-old Chinese man. Histological examination of the excised specimen disclosed spindle-shaped cells disposed in short fascicles as well as randomly in association with areas of varying cellularity, keloidal hyalinisation of the stroma and haemangiopericytoma-like vessels. The tumour cells were CD34-, bcl-2- and CD99-positive. Since histological features may not accurately predict the biological behaviour of this tumour, careful long-term follow-up is advocated.

Smooth muscle lesions of the large bowel, excluding the rectum, are generally rare, and diffuse smooth muscle lesions, termed leiomyomatosis, are even rarer. In this report, we document, for the first time, leiomyomatosis-like lymphangioleiomyomatosis (LAM) of the ascending, transverse, and descending colon in association with bilateral renal angiomyolipoma (AML) in a 30-year-old Chinese female with tuberous sclerosis complex (TSC). She presented with protracted constipation for which a colectomy was performed. Histology disclosed multiple confluent nodular CD34 and CD117 negative smooth muscle proliferation within the large bowel wall, whereas the renal biopsy revealed typical features of AML. Interestingly, the epithelioid smooth muscle cells of both the colonic and renal lesions were HMB45 positive, suggesting that leiomyomatosis-like LAM of the colon, pulmonary LAM and AML are closely related entities. The patient remained free of complications for the last five years after surgery. Leiomyomatosis-like LAM of the large bowel probably represents another manifestation of the tendency of TSC to be associated with proliferative lesions.

Langerhans cell histiocytosis (LCH) is a rare illness, and the disease afflicting the thyroid gland is very uncommon, even in the presence of multisystem involvement. In this report, we document histologically, for the first time, concurrent involvement of the thyroid and parathyroid glands by LCH. A young Chinese woman with a history of diabetes insipidus and hypogonadism underwent a total thyroidectomy for enlarged thyroid gland secondary to LCH causing airway obstruction. Microscopic examination of the excised specimen disclosed CD1a- and S-100-positive LCH cells involving the thyroid and parathyroid glands. In a patient with LCH affecting the thyroid gland, parathyroid gland disease should be suspected when the serum calcium levels are depressed in association with an inappropriate serum parathyroid hormone level, such as a normal parathyroid hormone level in this case.

Hepatic adenomas are benign liver tumors found mostly in young women with a history of oral contraceptive usage. They commonly present with abdominal pain from the tumor mass effect, bleeding, or rupture. We report a case of a young woman with a giant hepatic adenoma presenting with chronic iron deficiency anemia, requiring repeated blood transfusion. The mass was an incidental finding with typical features of a hepatic adenoma. Resection was performed and the hemoglobin remained stable up to the present fourth year of follow-up. This is an unusual presentation for which an association is investigated here. There was no evidence of intra-tumoral bleed but reverse-transcribed real-time PCR revealed higher tumor hepcidin RNA expression. Chronic iron deficiency anemia can be an initial presenting problem in patients with hepatic adenomas. Its cause may be multifactorial but the role of hepcidin-mediated anemia needs further evaluation in future cases.

Background Kidney involvement in non-Hodgkin lymphoma is well recognized and glomerulonephritis, when present, has been commonly reported to be associated with a membranoproliferative pattern. Case presentation We report a case of a 58-year-old lady with a recurrence of non-Hodgkin MALT B-cell lymphoma, presenting with acute kidney injury, nephrotic range proteinuria and a cellular urinalysis. She underwent a renal biopsy that showed a severe diffuse proliferative and exudative lupus-like glomerulonephritis, which is likely paraneoplastic in nature. We discuss the differential diagnosis and possible pathogenesis of glomerular injury in lymphoma-related proliferative glomerulonephritis. Conclusion Differentiating between true lupus nephritis and a paraneoplastic glomerulonephritis is important, as it would have significant implications on treatment and clinical course.

We present a case of a 54-year-old Chinese female with no known medical history presenting with epigastric pain. The biopsies revealed expansion of the lamina propria by dense lymphoplas-macytic infiltrate comprising small lymphocytes with clear cytoplasm, forming lymphoepithelial lesions. The initial morphological impression was that of an extranodal marginal zone lymphoma (MALT); however, the concomitant expression of CD20 and CD3 in the abnormal lymphocytes was unusual, prompting additional workup which showed CD2, CD5 and CD8 positivity in the tumour cells without Pax5 expression. Polymerase chain reaction revealed monoclonal T-cell receptor gene rearrangement and the absence of a clonal immunoglobulin heavy chain (IgH) gene rearrangement, thus confirming the T-cell phe-notype of the neoplastic lymphocytes. As peripheral T-cell lymphoma may display myriads of morphological appearance and is generally associated with a poorer prognosis as compared to a low grade B-cell lymphoma such as MALT lymphoma, awareness of its ability to aberrantly express B cell phenotype such as CD19, CD20 and CD79a is pivotal in preventing a misdiagnosis. In such an instance, a judicious application of a panel of immunohistochemistry stains in conjunction with molecular studies will assist in establishing the correct diagnosis.