Olfaction in the Anthropocene: NO3 negatively affects floral scent and nocturnal pollination

There is growing concern about sensory pollutants affecting ecological communities. Anthropogenically enhanced oxidants [ozone (O3) and nitrate radicals (NO3)] rapidly degrade floral scents, potentially reducing pollinator attraction to flowers. However, the physiological and behavioral impacts on pollinators and plant fitness are unknown. Using a nocturnal flower-moth system, we found that atmospherically relevant concentrations of NO3 eliminate flower visitation by moths, and the reaction of NO3 with a subset of monoterpenes is what reduces the scent's attractiveness. Global atmospheric models of floral scent oxidation reveal that pollinators in certain urban areas may have a reduced ability to perceive and navigate to flowers. These results illustrate the impact of anthropogenic pollutants on an animal's olfactory ability and indicate that such pollutants may be critical regulators of global pollination.

Protocol for mapping the metabolome and lipidome of medulloblastoma cells using liquid chromatography-mass spectrometry

Liquid chromatography-mass spectrometry (LC-MS)-based metabolomics and lipidomics have recently been used to show that MYC-amplified group 3 medulloblastoma tumors are driven by metabolic reprogramming. Here, we present a protocol to extract metabolites and lipids from human medulloblastoma brain tumor-initiating cells and normal neural stem cells. We describe untargeted LC-MS methods that can be used to achieve extensive coverage of the polar metabolome and lipidome. Finally, we detail strategies for metabolite identification and data analysis. For complete details on the use and execution of this protocol, please refer to Gwynne et al.1.

Cancer-selective metabolic vulnerabilities in MYC-amplified medulloblastoma

MYC-driven medulloblastoma (MB) is an aggressive pediatric brain tumor characterized by therapy resistance and disease recurrence. Here, we integrated data from unbiased genetic screening and metabolomic profiling to identify multiple cancer-selective metabolic vulnerabilities in MYC-driven MB tumor cells, which are amenable to therapeutic targeting. Among these targets, dihydroorotate dehydrogenase (DHODH), an enzyme that catalyzes de novo pyrimidine biosynthesis, emerged as a favorable candidate for therapeutic targeting. Mechanistically, DHODH inhibition acts on target, leading to uridine metabolite scarcity and hyperlipidemia, accompanied by reduced protein O-GlcNAcylation and c-Myc degradation. Pyrimidine starvation evokes a metabolic stress response that leads to cell-cycle arrest and apoptosis. We further show that an orally available small-molecule DHODH inhibitor demonstrates potent mono-therapeutic efficacy against patient-derived MB xenografts in vivo. The reprogramming of pyrimidine metabolism in MYC-driven medulloblastoma represents an unappreciated therapeutic strategy and a potential new class of treatments with stronger cancer selectivity and fewer neurotoxic sequelae.

Quantitative MRI findings indicate diffuse white matter damage in Susac Syndrome

Background

Susac Syndrome (SuS) is an autoimmune endotheliopathy impacting the brain, retina and cochlea that can clinically mimic multiple sclerosis (MS).

Objective

To evaluate non-lesional white matter demyelination changes in SuS compared to MS and healthy controls (HC) using quantitative MRI.

Methods

3T MRI including myelin water imaging and diffusion basis spectrum imaging were acquired for 7 SuS, 10 MS and 10 HC participants. Non-lesional white matter was analyzed in the corpus callosum (CC) and normal appearing white matter (NAWM). Groups were compared using ANCOVA with Tukey correction.

Results

SuS CC myelin water fraction (mean 0.092) was lower than MS(0.11, p = 0.01) and HC(0.11, p = 0.04). Another myelin marker, radial diffusivity, was increased in SuS CC(0.27μm2/ms) compared to HC(0.21μm2/ms, p = 0.008) and MS(0.23μm2/ms, p = 0.05). Fractional anisotropy was lower in SuS CC(0.82) than HC(0.86, p = 0.04). Fiber fraction (reflecting axons) did not differ from HC or MS. In NAWM, radial diffusivity and apparent diffusion coefficient were significantly increased in SuS compared to HC(p < 0.001 for both measures) and MS(p = 0.003, p < 0.001 respectively).

Conclusions

Our results provided evidence of myelin damage in SuS, particularly in the CC, and more extensive microstructural injury in NAWM, supporting the hypothesis that there are widespread microstructural changes in SuS syndrome including diffuse demyelination.

Clinical calculator predictive of chemotherapy benefit in stage 1A uterine papillary serous cancers

OBJECTIVE

Determine the utility of a clinical calculator to predict the benefit of chemotherapy in stage IA uterine papillary serous cancer (UPSC).

PATIENTS AND METHODS

Data were collected from NCDB from years 2010-2014. Based on demographic and surgical characteristics, a clinical score was developed using the random survival forest machine learning algorithm.

RESULTS

Of 1,751 patients with stage IA UPSC, 1,012 (58%) received chemotherapy and 739 (42%) did not. Older age (HR 1.06), comorbidities (HR 1.31), larger tumor size (HR 1.27), lymphovascular invasion (HR 1.86), positive peritoneal cytology (HR 2.62), no pelvic lymph node dissection (HR 1.51), and no chemotherapy (HR 2.16) were associated with poorer prognosis. Compared to no chemotherapy, patients who underwent chemotherapy had a 5-year overall survival of 80% vs. 67%. To better delineate those who may derive more benefit from chemotherapy, we designed a clinical calculator capable of dividing patients into low, moderate, and high-risk groups with associated 5-year OS of 86%, 73%, and 53%, respectively. Using the calculator to assess the relative benefit of chemotherapy in each risk group, chemotherapy improved the 5-year OS in the high (42% to 64%; p < 0.001) and moderate risk group (66% to 79%; p < 0.001) but did not benefit the low risk group (84% to 87%; p = 0.29).

CONCLUSION

Our results suggest a clinical calculator is useful for counseling and personalizing chemotherapy for stage IA UPSC.

Cannabis-based product use in a multiple sclerosis cohort

Objective

The objective of this study was to characterize the use of cannabis-based products (CBPs) by multiple sclerosis (MS) patients who attend the University of British Columbia Hospital (UBCH) MS clinic.

Methods

All patients attending the UBCH MS clinic from January to March 2018 were invited to participate in an anonymous survey that included: patient demographics (sex, age and employment status), self-reported MS-specific data (subtype, disease duration, previous and current disease modifying therapies, symptomatic medications) and CBP use (formulation, frequency, perceived benefits/side-effects). A second cohort of retrospective patient data (CBP use, sex, age, disease subtype and Expanded Disability Status Scale) was extracted from the UBCH MS clinic electronic medical record (EMR).

Results

Of 600 surveys distributed, 188 were returned with completed CBP usage. CBP use was daily for 19% (n = 37), weekly for 6% (n = 11), monthly for 4% (n = 7), rarely for 21% (n = 39) and 50% (n = 94) never used. Of the CBP users (daily, weekly and monthly), CBP use included: oral (n = 43/55), smoked/vaporized (n = 42/55), topical (n = 14/55) and mucosal (n = 5/55). EMR data was available for 561 MS patients where cannabis use/non-use was documented. CBP users represented 19% (107/561).

Conclusions

CBP use is common based on volunteer reporting, with approximately one out of four patients who attend the UBCH MS clinic using CBPs.

Progression-free and overall survival in ovarian cancer patients treated with CVac, a mucin 1 dendritic cell therapy in a randomized phase 2 trial

Background

CAN-003 was a randomized, open-label, Phase 2 trial evaluating the safety, efficacy and immune outcomes of CVac, a mucin 1 targeted-dendritic cell (DC) treatment as a maintenance therapy to patients with epithelial ovarian cancer (EOC).

Methods

Patients (n = 56) in first (CR1) or second clinical remission (CR2) were randomized (1:1) to standard of care (SOC) observation or CVac maintenance treatment. Ten doses were administered over 56 weeks. Both groups were followed for progression-free survival (PFS) and overall survival (OS).

Results

Fifty-six patients were randomized: 27 to SOC and 29 to CVac. Therapy was safe with only seven patients with Grade 3–4 treatment-emergent adverse events. A variable but measurable mucin 1 T cell-specific response was induced in all CVac-treated and some standard of care (SOC) patients. Progression free survival (PFS) was not significantly longer in the treated group compared to SOC group (13 vs. 9 months, p = 0.36, hazard ratio [HR] = 0.73). Analysis by remission status showed in the CR1 subgroup a median PFS of 18 months (SOC) vs. 13 months (CVac); p = 0.69 (HR = 1.18; CI 0.52–2.71). However CR2 patients showed a longer median PFS in the CVac-treated group (median PFS not yet reached, >13 vs. 5 months; p = 0.04, HR = 0.32 CI). OS for CR2 patients at 42 months of follow-up showed a difference of 26 months for SOC vs. > 42 months for CVac-treated (as median OS had not been reached; HR = 0.17 (CI 0.02–1.4) with a p = 0.07).

Conclusions

CVac, a mucin 1-dendritic cell maintenance treatment was safe and well tolerated in ovarian cancer patients. A variable but observed CVac-derived, mucin 1-specific T cell response was measured. Notably, CR2 patients showed an improved PFS and lengthened OS. Further studies in CR2 ovarian cancer patients are warranted (NCT01068509).

Trial registration

NCT01068509. Study Initiation Date (first patient screened): 20 July 2010. Study Completion Date (last patient observation): 20 August 2013, the last patient observation for progression-free survival; 29 April 2015, the last patient was documented regarding overall survival.

Overview of a chemoresponse assay in ovarian cancer

The objective of this review is to summarize recent scientific and medical literature regarding chemoresponse assays or chemotherapy sensitivity and resistance assays (CSRAs), specifically as applied to epithelial ovarian cancer. A total of sixty-seven articles, identified through PubMed using the key words “in vitro chemoresponse assay,” “chemo sensitivity resistance assay,” “ATP,” “HDRA,” “EDR,” “MiCK,” and “ChemoFx,” were reviewed. Recent publications on marker validation, including relevant clinical trial designs, were also included. Recent CSRA research and clinical studies are outlined in this review. Published findings demonstrate benefits regarding patient outcome with respect to recent CSRAs. Specifically, analytical and clinical validations, as well as clinical utility and economic benefit, of the most common clinically used CSRA in the United States support its use to aid in making effective, individualized clinical treatment selections for patients with ovarian cancer.

Viral fitness implications of variation within an immunodominant CD8+ T-cell epitope of HIV-1

Cytotoxic T-lymphocyte (CTL) epitopes within the HIV genome are subject to negative and positive selective pressures, the balance of which influences CTL escape at a given epitope. We investigated whether viral fitness requirements dictate conservation of the HLA-A2 restricted immunodominant epitope SLYNTVATL (SL9). Viral clones incorporating changes throughout the SL9 epitope region were compared to consensus SL9 virus in terms of replication kinetics and relative viral fitness. Constructs recapitulating in vivo SL9-CTL escape variants showed markedly little effect on replication and fitness, as did non-natural conservative mutations targeting immunologically relevant positions of the epitope. Although certain residues of the epitope were constrained by viral requirements, our research reveals that there are multiple SL9 variants that are well tolerated virologically but fail to arise in vivo. In light of this data, assumptions regarding the balance of immune and viral selective pressures on this immunodominant epitope sequence need to be reassessed.

Fluid Resuscitation in Burns: An Update

Fluid resuscitation has been a mainstay in the treatment of major burns for over 50 years. Fluids must be commenced as soon as possible prior to transfer to a specialist unit in order to minimise burn wound conversion and reduce the incidences of burn shock, post-burn renal failure, life-threatening electrolyte disturbances and mortality. Due to the lack of robust evidence, uncertainty exists regarding the type of fluid, the rate of fluid administration and method of monitoring fluid resuscitation in these patients. The advances in our understanding of burn pathology and technology may have rendered fluid resuscitation formulae, such as the Parkland, obsolete. This review aims to provide an up-to-date summary on the controversies and advances in burns fluid resuscitation to aid the emergency practitioner to make informed decisions.

The impact of the absolute number and ratio of positive lymph nodes on survival of endometrioid uterine cancer patients

The aim of the study was to determine the impact of the absolute number and ratio of positive lymph nodes on the survival in node-positive endometrioid uterine cancer. Data were obtained from the National Cancer Institute Registry from 1988 to 2001. Analyses were performed using Kaplan–Meier and Cox proportional hazard methods. A total of 1222 women were diagnosed with stage IIIC-IV node-positive endometrioid corpus cancer. The 5-year disease-specific survival of women with 1, 2–5, and >5 positive nodes were 68.1, 55.1, and 46.1%, respectively (P<0.001). Increasing lymph node ratio, expressed as a percentage of positive nodes to total nodes identified (⩽10, >10–⩽50, and >50%), was associated with a decrease in survival from 77.3 to 60.7 to 40.9%, respectively (P<0.001). The absolute number of positive nodes and the lymph node ratio remained significant after adjusting for stage (IIIC vs IV) and the extent of lymphadenectomy (⩽20 vs >20 nodes). On multivariate analysis, the absolute number of positive nodes and lymph node ratio were significant independent prognostic factors for survival. Increasing absolute number of positive nodes and lymph node ratio are associated with a poorer survival in women with node-positive uterine cancers. The stratification of node-positive uterine cancer for prognostic and treatment purposes warrants further investigation.

A case of mixed adult Wilms' tumour and angiosarcoma responsive to carboplatin, etoposide and vincristine (CEO)

Here we report an unusual case of mixed Wilms' tumour and angiosarcoma in a 38-year-old female patient who presented with haematuria and right lower back pain. A computed tomographic (CT) scan confirmed a massive renal tumour associated with extensive retroperitoneal lymph node involvement, bony metastases and a right hip fracture. She was initially managed with palliative nephrectomy, which was followed by rapid postoperative deterioration. Histopathology revealed differentiated adult Wilms' tumour with renal angiosarcoma, whereas the pathology of the para-aortic lymph node and bone metastasis revealed angiosarcoma only. In view of her cachexia and cytopaenia, emergency chemotherapy was initiated using a modified regimen of carboplatin, etoposide and vincristine (CEO) in preference to the more traditional but less well-tolerated VAC (vincristine, actinomycin D, cyclophosphamide). Four cycles of this protocol yielded a dramatic response on re-staging CT scan. This case suggests that highly angiogenic tumours such as angiosarcoma may be effectively palliated using agents usually reserved for refractory Wilms' tumour, and supports the view that adult Wilms' tumour is more sensitive to such agents.

The potential therapeutic role of lymph node resection in epithelial ovarian cancer: a study of 13918 patients

The aim of the study is to determine the role of lymphadenectomy in advanced epithelial ovarian cancer. The data were obtained from the Surveillance, Epidemiology and End Results (SEER) program reported between 1988 and 2001. Kaplan–Meier estimates and Cox proportional hazards regression models were used for analysis. Of 13 918 women with stage III–IV epithelial ovarian cancer (median age: 64 years), 87.9% were Caucasian, 5.6% African Americans, and 4.4% Asians. A total of 4260 (30.6%) underwent lymph node dissections with a median number of six nodes reported. For all patients, a more extensive lymph node dissection (0, 1, 2–5, 6–10, 11–20, and >20 nodes) was associated with an improved 5-year disease-specific survival of 26.1, 35.2, 42.6, 48.4, 47.5, and 47.8%, respectively (P<0.001). Of the stage IIIC patients with nodal metastases, the extent of nodal resection (1, 2–5, 6–10, 11–20, and >20 nodes) was associated with improved survivals of 36.9, 45.0, 47.8, 48.7, and 51.1%, respectively (P=0.023). On multivariate analysis, the extent of lymph node dissection and number of positive nodes were significant independent prognosticators after adjusting for age, year at diagnosis, stage, and grade of disease. The extent of lymphadenectomy is associated with an improved disease-specific survival of women with advanced epithelial ovarian cancer.

Ovarian cancer in younger vs older women: a population-based analysis

To compare the clinico-pathologic prognostic factors and survival of younger vs older women diagnosed with epithelial ovarian cancer. Demographic, clinico-pathologic, treatment, and surgery information were obtained from patients with ovarian cancer from the Surveillance, Epidemiology, and End Results Program from 1988 to 2001 and analysed using Kaplan–Meier estimates. Of 28 165 patients, 400 were <30 years (very young), 11 601 were 30–60 (young), and 16 164 were >60 (older) years of age. Of the very young, young, and older patients, 261 (65.3%), 4664 (40.2%), and 3643 (22.5%) had stage I–II disease, respectively (P<0.001). Across all stages, very young women had a significant survival advantage over the young and older groups with 5-year disease-specific survival estimates at 78.8% vs 58.8 and 35.3%, respectively (P<0.001). This survival difference between the age groups persists even after adjusting for race, stage, grade, and surgical treatment. Reproductive age (16–40 years) women with stage I–II epithelial ovarian cancer who received uterine-sparing procedures had similar survivals compared to those who underwent standard surgery (93.3% vs 91.5%, P=0.26). Younger women with epithelial ovarian cancer have a survival advantage compared to older patients.

Uterine papillary serous and clear cell carcinomas predict for poorer survival compared to grade 3 endometrioid corpus cancers

To compare the survival of women with uterine papillary serous carcinoma (UPSC) and clear cell carcinoma (CC) to those with grade 3 endometrioid uterine carcinoma (G3EC). Demographic, pathologic, treatment, and survival information were obtained from the Surveillance, Epidemiology, and End Results Program from 1988 to 2001. Data were analysed using Kaplan–Meier and Cox proportional hazards regression methods. Of 4180 women, 1473 had UPSC, 391 had CC, and 2316 had G3EC cancers. Uterine papillary serous carcinoma and CC patients were older (median age: 70 years and 68 vs 66 years, respectively; P<0.0001) and more likely to be black compared to G3EC (15 and 12% vs 7%; P<0.0001). A higher proportion of UPSC and CC patients had stage III–IV disease compared to G3EC patients (52 and 36% vs 29%; P<0.0001). Uterine papillary serous carcinoma, CC and G3EC patients represent 10, 3, and 15% of endometrial cancers but account for 39, 8, and 27% of cancer deaths, respectively. The 5-year disease-specific survivals for women with UPSC, CC and G3EC were 55, 68, and 77%, respectively (P<0.0001). The survival differences between UPSC, CC and G3EC persist after controlling for stage I–II (74, 82, and 86%; P<0.0001) and stage III–IV disease (33, 40, and 54; P<0.0001). On multivariate analysis, more favourable histology (G3EC), younger age, and earlier stage were independent predictors of improved survival. Women with UPSC and CC of the uterus have a significantly poorer prognosis compared to those with G3EC. These findings should be considered in the counselling, treating and designing of future trials for these high-risk patients.

A method of drusen measurement based on reconstruction of fundus background reflectance

BACKGROUND

The hallmarks of age related macular degeneration (AMD) are the subretinal deposits known as drusen. Current manual methods of drusen segmentation and quantification are laborious and subjective. The authors introduced a digital method and tested it for accuracy and reliability.

METHODS

Fourteen eyes with drusen were selected. The authors digitally reconstructed the macular background using normal background areas ("dots") fitted to quadratic polynomials in two zones. The model was used to level the reflectance for the purpose of segmenting drusen by a global threshold. Measurements of drusen areas were compared with those of a semi-automated background levelling technique and manual drawings from stereo pairs.

RESULTS

Intraobserver reproducibility had standard deviations from 0.1% to 4.1%. Interobserver reproducibility yielded 95% limits of agreement of -2.7% to 6.3%. The dots method compared with manual drawings and with the semi-automated method had 95% limits of agreement of -8.3% to 2.8% and -7.1% to 4.8%, respectively.

CONCLUSIONS

The dots method was reproducible and accurate with respect to validated methods. It provided less total operating time and greater precision than that of standard fundus photo grading. With implementation of commercial software, this technique for macular image analysis has potential for use in clinical research.

HPV infection and number of lifetime sexual partners are strong predictors for 'natural' regression of CIN 2 and 3

The aim of this paper was to evaluate the factors that predict regression of untreated CIN 2 and 3. A total of 93 patients with colposcopic persistent CIN 2 and 3 lesions after biopsy were followed for 6 months. Human papillomavirus (HPV) types were determined by polymerase chain reaction at enrolment. We analysed the biologic and demographic predictors of natural regression using univariate and multivariate methods. The overall regression rate was 52% (48 out of 93), including 58% (22 out of 38) of CIN 2 and 47% (26 out of 55) of CIN 3 lesions (P=0.31 for difference). Human papillomavirus was detected in 84% (78 out of 93) of patients. In univariate analysis, 80% (12 out of 15) of lesions without HPV regressed compared to 46% (36 out of 78) of lesions with HPV infection (P=0.016). Women without HPV and those who had a resolution of HPV had a four-fold higher chance of regression than those with persistent HPV (relative odds=3.5, 95% CI=1.4-8.6). Women with five or fewer lifetime sexual partners had higher rates of regression than women with more than five partners (P=0.003). In multivariate analysis, HPV status and number of sexual partners remained as significant independent predictors of regression. In conclusion, HPV status and number of lifetime sexual partners were strongly predictive of regression of untreated CIN 2 and 3.

The new World Health Organization classification of lymphomas: the past, the present and the future

The REAL Classification of lymphomas, proposed in 1994, represents a new paradigm in lymphoma classification, consisting of a list of biologic entities defined by clinicopathologic and immunogenetic features. The non-Hodgkin's lymphomas comprise precursor lymphoblastic and mature cell neoplasms of B, T or putative natural killer cell lineage. An individual entity can exhibit a range of morphologic appearances and a range of clinical behavior. The categories in Hodgkin's lymphomas are identical to the widely used Rye classification except for the additional of a new category termed 'lymphocyte-rich classical Hodgkin's lymphoma'. The REAL classification has been validated by a major multi-institutional study involving 1378 cases (The Non-Hodgkin's Lymphoma Classification Project), showing that it is both reproducible and clinically relevant. The new World Health Organization classification of hematopoietic and lymphoid tumors, to be published in 2001, is a joint project of the Society for Hematopathology and European Association of Hematopathologists, under the auspices of the World Health Organization. This classification includes not only lymphoid neoplasms, but also myeloid, histiocytic and mast cell neoplasms. The lymphoma component of the classification is merely an update of the REAL classification, with minor changes necessitated by new information that has become available since its proposal. A conceptual grouping of the non-Hodgkin's lymphomas into four categories (indolent, aggressive, highly aggressive, and localized indolent) is also presented in this review. The next major impetus influencing the approach to lymphoma classification will no doubt be molecular genetics, in particular DNA microarrays, which will yield an enormous amount of new data that will aid in the understanding of lymphomas.

Dedifferentiation of adenoid cystic carcinoma: report of a case implicating p53 gene mutation

Adenoid cystic carcinoma is an indolent tumour with an unfavorable long-term prognosis. Dedifferentiation of adenoid cystic carcinoma, which is associated with an accelerated clinical course, has recently been described. We report a case with immunohistochemical and molecular workup to elucidate the likely mechanism of dedifferentiation. The patient, a 64-year-old woman, developed dedifferentiated adenoid cystic carcinoma of the submandibular gland ab initio, accompanied by cervical lymph node metastasis. Histologically, the low-grade adenoid cystic carcinoma merged gradually into an extensive dedifferentiated component that was composed of solid sheets and cords of anaplastic tumor cells with focal gland formation. Immunohistochemically, the dedifferentiated component, but not the adenoid cyst carcinoma component, showed strong overexpression of p53 protein and cyclin D1, as well as a higher Ki67 index. Molecular study confirmed the presence of p53 gene mutation selectively in the dedifferentiated component, suggesting a pivotal role of p53 gene alteration in the dedifferentiation process of adenoid cystic carcinoma.

Primary histiocytic lymphoma of the central nervous system: a neoplasm frequently overshadowed by a prominent inflammatory component

True histiocytic lymphoma, as defined by strict criteria, is a very rare neoplasm. We describe three cases occurring as primary tumors in the central nervous system. The patients, two females and one male, ranged in age from 11 to 69 years. The tumors involved the brain in two cases and spinal cord in one, with a size ranging from 7 to 17 mm. Two patients died at 4 months and 8 months, respectively, and one was alive with disease at 5 months. Pathologically, the tumors comprised groups and sheets of noncohesive large cells with pleomorphic vesicular nuclei, distinct nucleoli, and abundant eosinophilic cytoplasm. A dense inflammatory infiltrate consisting of neutrophils, lymphocytes, plasma cells, and histiocytes was present, with multiple foci of necrosis and abscess formation. All three cases demonstrated an identical immunophenotype: positive for CD68 and lysozyme; focally positive for S-100 protein, CD45RB, and CD4; and negative for CD3, CD20, CD21/CD35, CD1a, CD30, ALK1, myeloperoxidase, glial fibrillary acidic protein, and cytokeratin. The proliferative index ranged from 20% to 35%. Ultrastructural examination further confirmed the histiocytic nature of the tumor cells, characterized by irregularly folded or multisegmented nuclei and abundant cytoplasm containing lysosomes; Birbeck granules, interdigitating cell processes, and cell junctions were not found. Although the presence of abundant inflammatory cells could obscure the neoplastic histiocytes, making the distinction from inflammatory conditions difficult, awareness of this unusual histologic feature and the invariable finding of pleomorphic cells in some areas of the lesion permit the correct diagnosis to be made.

Capsular intravascular endothelial hyperplasia: a peculiar form of vasoproliferative lesion associated with thyroid carcinoma

AIMS

Florid vasoproliferative processes are uncommon in the thyroid gland. We report three cases of an unusual vasoproliferation involving the capsular blood vessels of thyroid carcinoma.

METHODS AND RESULTS

The histological diagnoses of the three cases were made on conventional histological sections. Two cases were minimally invasive follicular carcinomas and one case was an encapsulated variant of papillary carcinoma. Some blood vessels in the tumour fibrous capsule were filled with spindly cellular proliferations forming irregular vascular clefts and papillae. Immunohistochemical studies for CD31, CD34 and muscle-specific actin confirmed that the spindly cells were mostly endothelial cells variably supported by pericytes.

CONCLUSION

This peculiar intravascular endothelial hyperplasia by itself should not be mistaken for vascular invasion by tumour, but evidence of malignancy must be diligently sought by extensive sampling because the lesion has thus far been consistently associated with malignant thyroid neoplasms.

Detection of choledocholithiasis by EUS in acute pancreatitis: a prospective evaluation in 100 consecutive patients

BACKGROUND

ERCP is the standard for detection of choledocholithiasis in patients with acute biliary pancreatitis, and, if performed early, ERCP decreases morbidity. However, there are procedure-related complications. The aim of the present prospective study was to evaluate the ability of EUS to detect choledocholithiasis in patients presenting with acute pancreatitis.

METHODS

The study group comprised 100 consecutive patients who presented with acute pancreatitis. EUS, and immediately thereafter, ERCP were performed by separate blinded examiners within 24 hours of admission. The diagnostic accuracy of EUS in identifying gallbladder stones was compared with that of transcutaneous US. The diagnostic accuracy of EUS in detecting choledocholithiasis was then compared with that of US and ERCP based on the results of endoscopic instrumentation of the bile duct after sphincterotomy.

RESULTS

EUS was more sensitive than US in detecting gallbladder stones (100% vs. 84%, p < 0.005). The sensitivities of ERCP and EUS for choledocholithiasis were both 97%, and the overall accuracies were 96% and 98%, respectively, with no significant difference. EUS detected the absence of choledocholithiasis in 65 of 66 patients (specificity = 98%). Endosonographic examination was successful in all patients, whereas ERCP was unsuccessful in 5 patients (p > 0.05). Post-endoscopic sphincterotomy bleeding developed in 4 patients; there was no EUS-related morbidity (p > 0.05).

CONCLUSION

EUS is more sensitive than US in detecting biliary stones in patients with acute pancreatitis. It is as accurate as ERCP in detecting choledocholithiasis. EUS can be used to select patients with acute pancreatitis who require therapeutic ERCP, thus avoiding diagnostic ERCP and its associated potential for complications in the majority of patients.

Clear cell variant of fibrolamellar carcinoma of the liver

Fibrolamellar carcinoma of the liver is a distinctive variant of hepatocellular carcinoma characterized histologically by trabeculae of oncocytic cells with intervening lamellae of collagen fibers. We describe a case with a prominent component of clear cells, a feature not previously recognized in this tumor type. The patient was a 59-year-old woman incidentally found to have a solitary liver tumor, measuring 5 cm. Pathologic examination revealed a circumscribed, firm, tan tumor with peculiar concentric streaks. Oncocytic cells and clear cells were arranged in trabeculae separated by lamellae of collagen or sinusoids. The clear cells possessed abundant finely reticulated clear cytoplasm, which was highlighted by trichrome stain and immunostaining with antimitochondria antibody. Ultrastructurally, the cytoplasm of the clear cells was packed with empty membrane-bound vesicles that occasionally contained short cristae. The features suggested that the clear cell change resulted from ballooning and rarefactive changes of mitochondria. Clear cell fibrolamellar carcinoma should not be confused with conventional clear cell hepatocellular carcinoma, since the former is associated with a more favorable prognosis.

Sinonasal angiosarcoma with marrow involvement at presentation mimicking malignant lymphoma: cytogenetic analysis using multiple techniques

Angiosarcoma of the head and neck most commonly involves the skin of the scalp or face; primary involvement of the sinonasal region is exceedingly rate. We report a patient with sinonasal angiosarcoma who showed marrow involvement at presentation. Marrow aspiration smears showed many large, often segregated blast-like cells, mimicking malignant lymphoma. However, trephine biopsy revealed formation of anastomosing vascular spaces by the tumor cells and immunoreactivity for CD31, supporting a diagnosis of angiosarcoma. DNA ploidy analysis showed an apparent diploidy. Nevertheless, conventional cytogenetics demonstrated very complex chromosomal abnormalities with the presence of multiple hypodiploid clones, together with several near-triploid to near-tetraploid clones showing structural abnormalities involving chromosomes 1, 3, 4, 9, 14, 16, 17, 18, and 22. The identification of these karyotypic changes has been facilitated by the application of comparative genomic hybridization and spectral karyotyping.

Lace-like enhancement pattern of osteosarcoma of rib and liver metastasis in CT scans

The rib is an uncommon site of osteosarcoma. With the use of adjuvant chemotherapy and aggressive surgical resection of the metastatic pulmonary lesions, extrapulmonary metastases are becoming more clinically evident. Primary rib osteosarcoma with extrapulmonary metastasis is exceedingly rare. A case is reported, showing that the pattern of metastasis of rib osteosarcoma is similar to that of primary bone osteosarcoma. The liver metastasis occurred after resection of the metastatic pulmonary lesions. A CT scan of the primary rib lesion and liver metastasis both showed a lace-like enhancement pattern, its histological appearance corresponding with neoplastic osteoid. With the increasing use of CT abdomen for localization of extrapulmonary metastases, lace-like enhancement may be seen more readily in the future.

Determinants of continuous positive airway pressure compliance in a group of Chinese patients with obstructive sleep apnea

OBJECTIVE

To assess continuous positive airway pressure (CPAP) compliance and factors associated with CPAP compliance among Chinese patients with obstructive sleep apnea (OSA).

DESIGN

A prospective study of 112 consecutive patients with newly diagnosed OSA commencing CPAP treatment.

SETTING

A university teaching hospital.

MEASUREMENTS AND RESULTS

The following factors were evaluated for any correlation with objective CPAP compliance (effective mask pressure [hours per day]) at 1 month and 3 months: age, baseline apnea-hypopnea index (AHI), common OSA symptoms, minimum arterial oxygen saturation (SaO(2)), mean SaO(2), arousal index (AI), Epworth sleepiness scale (ESS), education level, CPAP levels, satisfaction with CPAP, side effects, and machine cost. There were 101 male and 11 female patients, with a mean (+/- SD) age of 45.6 +/- 1.2 years; body mass index, 29.3 +/- 5.2 kg/m(2); AI, 60 +/- 18/h; AHI, 48 +/- 24/h; minimum SaO(2) of 70 +/- 17%; and mean SaO(2) of 86 +/- 7%. ESS fell from 12.9 +/- 4.0 (baseline) to 5.2 +/- 4.7 at 3 months (p < 0.001). Objective CPAP compliance was 5.4 +/- 1.6 h/d and 5.3 +/- 1.6 h/d, while 75% and 72% of our patients were using CPAP objectively for > or = 4 h/d and at least 70% of the nights per week at 1 month and 3 months, respectively. Following univariate analysis of variance, a high baseline AHI (p = 0.006 and p = 0.004) was associated with higher objective CPAP compliance at 1 month and 3 months, respectively.

CONCLUSION

CPAP usage and compliance were high in this patient population. A high baseline AHI was the only significant independent predictor of better CPAP compliance.

Abdominopelvic sarcoma of perivascular epithelioid cells. Report of four cases in young women, one with tuberous sclerosis

The perivascular epithelioid cell has been proposed to be the unifying proliferating cell type in a number of lesions such as angiomyolipoma, lymphangiomyomatosis, clear cell "sugar" tumor and renal capsuloma. With the exception of rare examples of angiomyolipoma, they are non-metastasizing. We report four examples of a new member of this family of perivascular epithelioid cell neoplasms that occur in abdominopelvic location and show metastatic properties. The patients, all women, were aged 19 to 41 years (mean, 32), and presented with a tumor mass involving the serosa of the ileum, uterus or pelvic cavity. Morphologically, the tumors were composed of sheets of large polygonal cells with glycogen-rich clear or eosinophilic cytoplasm and moderately pleomorphic nuclei, traversed by a delicate vasculature, mimicking clear cell carcinoma. There were areas of coagulative necrosis and occasional mitotic figures. Intracytoplasmic brown pigment was present in two cases. Spindly cells, smooth muscle and fat were absent. Lymphovascular invasion was present in all, lymph node metastasis was documented in two and metastasis to the ovary was present in one case. Two patients developed widespread metastatic disease after 10 and 28 months from diagnosis. One patient showed the clinical signs of tuberous sclerosis. In spite of the epithelial-like appearance, the tumor cells were negative for epithelial markers but were strongly positive with the melanogenesis-related marker HMB45. Another melanogenesis marker (MART-1) was positive in two cases. Other markers including S-100 protein, vimentin, muscle-specific actin, desmin and chromogranin A were negative. Thus, these tumors are not readily classifiable in the existing schema of known entities, and show overlapping morpho-phenotypic features of clear cell "sugar" tumor of the lung and epithelioid angiomyolipoma. We consider them as sarcomas composed of a pure population of uncommitted perivascular epithelioid cell, that lack modulation toward smooth muscle or adipose cells.

Anaplastic lymphoma kinase expression in inflammatory pseudotumors

Anaplastic lymphoma kinase (ALK), a hallmark of anaplastic large cell lymphoma, has recently been implicated in the genesis of some inflammatory pseudotumors (inflammatory myofibroblastic tumors) in children and young adults. The aim of this study was to determine the frequency of its expression among inflammatory pseudotumors, and to characterize the clinicopathologic features of the positive cases. Sixty-one cases of inflammatory pseudotumors were retrieved from the surgical pathology archives and consultation files. Paraffin sections were immunostained with the antibody ALK1. The patients ranged in age from 0.5 to 79 years (median age, 50 years), with 10 patients (16.4%) younger than 20 years. Five cases (8.2%) were ALK+, including two of six urogenital inflammatory myofibroblastic tumors, none of eight pulmonary inflammatory pseudotumors, three (one adrenal, one small bowel, one liver) of 31 extrapulmonary inflammatory pseudotumors, none of nine hepatic/splenic inflammatory pseudotumors expressing follicular dendritic cell markers and harboring Epstein-Barr virus, and none of seven inflammatory pseudotumors of the lymph node. When only those patients 40 years or younger were considered, the ALK positivity rate became 21.7% (five of 23). All five ALK+ cases occurred in young patients aged 0.5 to 37 years, who were alive and well at 3.5 to 17 years. The tumors exhibited a spectrum of histologic features typical of inflammatory pseudotumors/myofibroblastic tumors, but there was at least focal nuclear atypia. Immunostaining for ALK produced fibrillary or granular cytoplasmic staining in the neoplastic cells, sometimes with cell membrane accentuation. This study confirms that ALK is implicated in a proportion of inflammatory pseudotumors, and is generally associated with a favorable outcome. The results also support the heterogeneity of inflammatory pseudotumors, with the follicular dendritic cell/Epstein-Barr virus-positive cases and those occurring in lymph nodes representing different biologic entities.

Development of follicular dendritic cell sarcoma in hyaline-vascular Castleman's disease of the nasopharynx: tracing its evolution by sequential biopsies

AIMS

Hyaline-vascular Castleman's disease (HVCD) and follicular dendritic cell (FDC) sarcoma occurring in the nasopharynx are both extremely rare. We report the first case of transformation of the former into the latter as documented by sequential biopsies. The steps involved in the transformation were described in detail and the possible role of p53 studied.

METHODS AND RESULTS

The patient presented at the age of 23 years with nasopharyngeal HVCD. Hyaline- vascular Castleman's disease with FDC overgrowth was diagnosed in a recurrence 8 years later, and a frank FDC sarcoma developed at the same site 11 years after initial presentation. The patient remained disease-free 3 years after excision and adjuvant chemotherapy. The FDC sarcoma comprised swirling fascicles of spindly cells with indistinct cell borders. The tumour cells expressed the FDC markers CD21, CD35 and CNA.42 and in-situ hybridization for Epstein-Barr virus-encoded RNAs was negative. Over-expression of p53 protein was observed in the FDC sarcoma and an increased number of weakly p53-positive spindly cells could also be demonstrated in the HVCD specimen. This finding suggested a possible role of p53 in the evolution from HVCD to FDC sarcoma. Critical analysis of the literature shows that, among the 13 reported cases of FDC sarcoma associated with Castleman's disease, possible progression from the latter to the former is documented in only two cases.

CONCLUSIONS

The sequential changes observed in the current case provide further evidence to strengthen the role of HVCD as a possible precursor of FDC sarcoma. There is a possible role of p53 in the transformation process but confirmation by future studies is needed.

Inflammatory pseudotumor-like follicular dendritic cell tumor: a distinctive low-grade malignant intra-abdominal neoplasm with consistent Epstein-Barr virus association

Follicular dendritic cell (FDC) tumors are uncommon neoplasms that can involve lymph nodes or extranodal sites. They can exhibit a broad spectrum of histologic appearances and behavior, but the intra-abdominal ones usually pursue an aggressive course. The purpose of this study was to characterize a distinctive variant of FDC tumor morphologically mimicking inflammatory pseudotumor through analysis of the clinicopathologic features of 11 cases. The patients included 10 women and one man (age range, 19-61 years; median age, 40 years) who presented with abdominal discomfort or pain. Six patients had systemic symptoms such as marked weight loss, fever, or malaise. All tumors occurred in intra-abdominal sites: liver (n = 7), spleen (n = 3), and peripancreatic region (n = 1). Of the nine patients with follow-up data, six were alive and well, one developed recurrence at 9 years, and two had repeated recurrences over many years. Grossly, the tumors were usually solitary and fleshy, punctuated by areas of hemorrhage and necrosis. Histologically, in a background of abundant lymphocytes and plasma cells were dispersed spindle or ovoid cells with vesicular nuclei and distinct nucleoli. The degree of nuclear atypia was variable, and some nuclei could be grotesque or resemble Reed-Sternberg cells. Focally, spindle cell fascicles could be formed. The atypical cells were immunoreactive for FDC markers such as CD21/CD35, CD23, and CNA.42. In situ hybridization for Epstein-Barr virus (EBV)-encoded RNA was positive in all cases, remarkably highlighting the spindle cells and their atypia. EBV-latent membrane protein-1 was expressed commonly, albeit often focally and weakly. Therefore, inflammatory pseudotumor-like FDC tumor represents a distinctive variant of FDC tumor that differs from conventional FDC tumor in the following aspects: marked female predominance; selective localization in intra-abdominal sites, especially the liver and spleen; frequent presence of systemic symptoms; indolent behavior despite an intra-abdominal location; dispersed distribution of tumor cells and prominent lymphoplasmacytic infiltration; and consistent association with EBV.

Differential expression of p16/p21/p27 and cyclin D1/D3, and their relationships to cell proliferation, apoptosis, and tumour progression in invasive ductal carcinoma of the breast

In order to understand the intricate relationship of cell proliferation and apoptosis in tumour development, proliferation markers (Ki-67 and c-myc), apoptosis, cell-cycle inducers cyclin D1 and D3, and cell-cycle inhibitors p16(INK4), p21(CIP1), and p27(KIP1) were evaluated in ductal breast carcinoma. The heterogeneous nature of breast tumours provides a system by which the changes in cell-cycle genes can be explored under a wide range of proliferation and apoptotic indices. To address the above issues, immunohistochemical studies were conducted in 40 pairs of tumours and adjacent normal ductal tissues. The TUNEL method was used to identify apoptotic cells. Except for p27/KIP1, the proliferation (Ki-67, c-myc) and the apoptotic indexes together with levels of p16/INK4a, p21/CIP1, cyclin D1, and cyclin D3, were clearly elevated among tumour tissues, while absent in the adjacent normal tissues. Spearman correlation analysis indicated strong associations among apoptotic index, Ki-67, c-myc, and tumour grade. In addition, p21/CIP1 and cyclin D3 were positively correlated, while p16/INK4a, p27/KIP1, and cyclin D1 were negatively correlated with tumour grade. There was clear decoupling between p21 and p27, as well as decoupling between cyclin D1 and cyclin D3, in terms of their relationship to cell proliferation and apoptosis, indicating differential roles in tumour progression.

Vaginal hysterectomy as primary treatment of endometrial cancer in medically compromised women

OBJECTIVE

To study the survival, rates and patterns of recurrence, and perioperative morbidity in medically compromised women with endometrial cancer treated by primary vaginal hysterectomy.

METHODS

Fifty-one patients with endometrial cancer treated initially by vaginal hysterectomy between 1977 and 1999 were identified at the University of California, Irvine Medical Center and affiliated hospitals. Data were retrieved from hospital and office records. Statistical analysis, including Kaplan-Meier methods, was performed and the disease-specific survival rates were estimated. This study has 80% power to demonstrate a greater than 20% improvement in 5-year survival over historical controls.

RESULTS

Fifty-one women with uterine carcinoma clinically confined to the uterus underwent primary vaginal hysterectomy with (n = 26) or without (n = 25) salpingo-oophorectomy. Eighty-four percent were obese with a body mass index greater than 27. Additional risk factors for surgical complications included hypertension (57%), diabetes mellitus (27%), and cardiovascular disease (18%). One-third of patients had three or more risk factors. Surgical morbidity included one episode of acute hemorrhage necessitating transfusion and abdominal exploration. Blood transfusions were given to four additional patients. There were no perioperative deaths. Five women recurred and expired at a median of 13 months (range 3--53 months) after surgery. The 3- and 5-year disease-specific survival rates were 91.4% and 88.0%, respectively.

CONCLUSION

Vaginal hysterectomy for the initial treatment of early-stage endometrial cancer is associated with a high rate of cure and minimal morbidity. Thus, it may be considered a reasonable alternative to the abdominal approach in medically compromised women.

N-acetyl-serotonin reduces copper (I) ion-induced lipid peroxidation in bovine retinal homogenates

PURPOSE

Chalcosis is an ocular condition caused by penetration injury of copper or its alloy, which leads to extensive ocular inflammation. N-acetyl-serotonin has recently been identified as a potent antioxidant against free radical stress. In this study, we determined the efficacy of N-acetyl-serotonin against the copper (I)-induced retinal lipid peroxidation.

METHODS

Copper (I)-treated (100 microM) bovine retinal homogenates were incubated with 6 different concentrations (i.e. 0.00, 0.25, 0.50, 1.00, 2.00 and 4.00 mM) of N-acetyl-serotonin or vitamin E. The malondialdehyde level was measured as an index of lipid peroxidation.

RESULTS

Copper (I) ions induced a significant dose-dependent increase in malondialdehyde (p=0.007). Co-incubation with N-acetyl-serotonin or vitamin E significantly suppressed the copper (I)-induced malondialdehyde production (p<0.0001). The concentration to inhibit 50% of damage for N-acetyl-serotonin and vitamin E were found to be 1.54 mM and 0.45 mM, respectively.

CONCLUSION

Although N-acetyl-serotonin is only 29% as effective as vitamin E in suppressing the copper (I)-induced lipid peroxidation, the present study supports a pharmacological potential of N-acetyl-serotonin combating free radical oxidative damages in the ocular tissues.

Timely topic: anaplastic lymphoma kinase (ALK) spreads its influence

Anaplastic lymphoma kinase (ALK) is normally not expressed in human tissues except selected sites in the nervous system. Its expression and constitutive activation as a result of a chromosomal translocation involving 2p23 plays a pivotal role in the genesis of anaplastic large cell lymphoma. ALK expression has been instrumental in defining a homogeneous subset from the category of anaplastic large cell lymphoma, characterised by occurrence in young patients, primary systemic presentation, favorable prognosis, a broad morphological spectrum, nuclear and/or cytoplasmic immunostaining for ALK protein, and a number of possible fusion partner genes such as NPM, ATIC, TFG, TPM3 and CLTCL. Recently ALK has been implicated in the genesis of another tumour type, the inflammatory myofibroblastic tumours. The ALK-positive examples occur in children and young adults, involving a variety of sites, such as the abdomen, mesentery, liver, bladder, mediastinum, lung and bone. The partner genes identified in some cases are TPM3 (tropomyosin 3) and TPM4 (tropomyosin 4). These molecular findings also further support the neoplastic nature of at least a subset of inflammatory myofibroblastic tumours.

Bone marrow involvement by nasal NK cell lymphoma at diagnosis is uncommon

To look for subtle evidence of marrow involvement in nasal NK cell lymphoma at diagnosis, we retrospectively studied trephine biopsy specimens from 25 consecutive patients by 2 sensitive techniques: CD56 immunohistochemistry and Epstein-Barr virus-encoded RNA in situ hybridization (EBER ISH). Only 2 patients had marrow involvement by NK cell lymphoma at diagnosis. In 3 additional patients, marrow involvement developed during or after systemic recurrence. All 5 positive cases were revealed by EBER ISH, but only 3 cases showed CD56 immunoreactivity. Among the 5 cases, only 2 were recognized by morphologic assessment. All 5 patients died, often within a short period, compared with a mortality of 50% for patients without demonstrable marrow involvement. Marrow involvement is distinctly uncommon in nasal NK cell lymphoma at diagnosis, and EBER ISH is the most sensitive technique for the demonstration of occult NK cell lymphoma. Despite the low frequency of marrow involvement in nasal NK cell lymphoma, EBER ISH is worthwhile to identify the minor subgroup of patients with a high likelihood of early death due to disease and when autologous bone marrow or peripheral blood stem cell transplantation is contemplated.

Immunostaining for thyroid transcription factor 1 and cytokeratin 20 aids the distinction of small cell carcinoma from Merkel cell carcinoma, but not pulmonary from extrapulmonary small cell carcinomas

OBJECTIVE

To study the expression of thyroid transcription factor 1 (TTF-1) and cytokeratin 20 (CK20) in pulmonary small cell carcinomas, extrapulmonary small cell carcinomas, and Merkel cell carcinomas, and thereby determine whether these markers are helpful in distinguishing these 3 groups of small cell neuroendocrine carcinomas.

MATERIALS AND METHODS

Immunostaining for TTF-1 and CK20 was performed in 102 cases of small cell carcinoma (pulmonary, 52; extrapulmonary, 50) and 23 cases of Merkel cell carcinoma. The results for the 3 groups were compared.

RESULTS

Thyroid transcription factor 1 was expressed in 82.7% of pulmonary small cell carcinomas, 42.0% of extrapulmonary small cell carcinomas (range, 33.3--53.3% for the various sites), and 0% of Merkel cell carcinomas. Cytokeratin 20 staining was consistently negative in pulmonary small cell carcinomas, and positive in 4.0% of extrapulmonary small cell carcinomas and 100% of Merkel cell carcinomas.

CONCLUSIONS

Immunostaining for TTF-1, especially when combined with immunostaining for CK20, can aid in the distinction between Merkel cell carcinoma and small cell carcinoma (both pulmonary and extrapulmonary). However, in individual cases, these markers cannot be used to distinguish between pulmonary and extrapulmonary small cell carcinomas due to the extensive overlap in immunophenotypes.

Trail making across languages

The effects of different language backgrounds on trail making tasks were examined in this study. The measures adopted were the Color Trails Test (CTT) and the Trail Making Test (TMT), the former being the culturally fair analogue of the latter. Eighty-four right-handed participants belonging to the Chinese-English Bilingual (CEB) and English Monolingual (EM) groups participated in this study. The results of between-group comparisons revealed no significant differences in performance on the two measures between our Chinese bilingual and English monolingual participants, except on the TMT-A. However, a within-group correlation indicated that performances on the TMT and CTT were highly correlated for the English sample, but not for the Chinese. These observations suggest that trail making tasks like the TMT and CTT are themselves generally fair across Chinese and English, but equivalence between them may be more language-specific. Furthermore, mastery of a language loaded on temporal sequencing like English may give an advantage in the completion of trail making tasks.

Consistent patterns of allelic loss in natural killer cell lymphoma

Natural killer (NK) cell lymphomas are a group of rare but highly aggressive malignancies. Clinically, they can be divided into nasal NK cell lymphomas, nonnasal NK cell lymphomas, and aggressive NK cell lymphoma/leukemia. To determine the patterns of genetic deletions in these tumors, we performed loss of heterozygosity (LOH) analysis on 15 cases (11 nasal and four nonnasal), and fluorescence in situ hybridization on three cases of aggressive lymphoma/leukemia. A panel of 41 microsatellite loci on chromosomes 6q, 11q, 13q, and 17p were investigated. LOH at chromosomes 6q and 13q was frequently detected in NK cell lymphomas, being found in 80 and 66.7% of cases, respectively. LOH at chromosomes 11q and 17p was less common, being found in 28.6 and 30.8% of cases, respectively. Most tumors showed multiple loci deletions at different chromosomal regions, but several patterns of LOH could be defined. LOH at chromosome 6q was found in 90.9% of nasal NK cell lymphomas, but only in 50% of nonnasal NK cell lymphomas. LOH at chromosome 13q was found in 63.6% of nasal NK cell lymphomas and 75% of nonnasal NK cell lymphomas. For nasal NK cell lymphomas, LOH at 13q was found in 33.3% of cases at presentation, but 100% of cases at relapse. Five tumors showed LOH in only one chromosomal region, involving 6q in three cases (two nasal and one nonnasal), and 13q in two cases (both nonnasal). For the three cases of aggressive NK cell lymphoma/leukemia studied by fluorescence in situ hybridization, DNA loss at 13q14 and 17p13 regions were demonstrated. 17p13 seemed to be more commonly involved in aggressive than nasal and nonnasal NK cell lymphomas. Our results suggested that consistent patterns of LOH could be defined in NK cell malignancies. These deleted loci may contain genes important in the initiation and progression of this lymphoma.

Hypocellular anaplastic large cell lymphoma mimicking inflammatory lesions of lymph nodes

The subgroup of T/null-cell primary systemic anaplastic large cell lymphoma that expresses anaplastic lymphoma kinase (ALK) constitutes a distinctive clinicopathologic entity that exhibits a broad morphologic spectrum. The examples predominated by small cells or showing a mixed cell population can be difficult to recognize as being neoplastic. We report four such cases with a remarkably hypocellular granulation tissue-like appearance, mimicking an inflammatory or reparative process. All patients were young and presented with lymphadenopathy in multiple sites. The lymph node biopsies showed a hypocellular appearance, with wide separation of the small to medium-sized lymphoid cells by edematous or fibromyxoid stroma. There were interspersed spindly neoplastic cells resembling myofibroblasts, sometimes forming short, sweeping fascicles, as well as histiocytes. Occasional large cells with atypical nuclei were identified. The larger lymphoid cells tended to form cuffs around the venules. In two cases, the capsule and fibrous trabeculae were markedly broadened with increased spindly cells, mimicking inflammatory pseudotumor of lymph node. Immunostaining showed dispersed and clustered CD30+ ALK+ cells, confirming a diagnosis of anaplastic large cell lymphoma. In conclusion, a diagnosis of hypocellular anaplastic large cell lymphoma requires a high index of suspicion. The young age of the patients and the presence of perivascular cuffs of larger lymphoid cells should provide the strongest clues to the correct diagnosis.

Follicular lymphoma with trisomy 18 and over-expression of BCL2 in the absence of t(14;18)(q32;q21)

A 66-year-old female who presented with cervical lymphadenopathy and splenomegaly was found to have large B-cell lymphoma on lymph node biopsy. However, trephine biopsy revealed involvement of the marrow by follicular lymphoma, and cytogenetic study showed an abnormal clone with 47,XX,+18.

Pulmonary sclerosing hemangioma consistently expresses thyroid transcription factor-1 (TTF-1): a new clue to its histogenesis

The histogenesis of pulmonary sclerosing hemangioma has remained controversial despite extensive studies by many investigators. The availability of an antibody to thyroid transcription factor-1 (TTF-1), which is expressed in type II pneumocytes and Clara cells, has prompted us to readdress this issue. Sixteen cases were immunostained with a panel of antibodies including TTF-1. The patients were predominantly women with an age range of 30 to 73 years (mean, 52 yrs). All tumors were solitary. The single male patient showed regional lymph node metastases, an unusual occurrence reported only once in the literature. All cases exhibited the classic histologic features, with variegated patterns. TTF-1 expression was observed in both the surface lining cells and the pale polygonal cells. The surface lining cells were epithelial membrane antigen (EMA)+ cytokeratin+ surfactant apoprotein A+, whereas the polygonal cells were EMA+ cytokeratin- surfactant apoprotein A-. The neuroendocrine markers synaptophysin and chromogranin were both negative. The metastatic deposits in the lymph nodes comprised only polygonal cells and exhibited an EMA+ cytokeratin- surfactant apoprotein A- TTF- 1+ immunophenotype. These results suggest that pulmonary sclerosing hemangioma is an epithelial neoplasm derived from primitive respiratory epithelium or incompletely differentiated type II pneumocyte or Clara cell.