PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “pathological subtype”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17Linked to original sources
PubMed1992

Retrospective studies of gastric subserosal (ss) cancer--in comparison to pm- and se-cancers.

The deepest gastric cancer invasion into the tela subserosa is expressed as the ss-cancer. Subserosal gastric cancers (ss) can be divided into 4 subtypes; ss alpha, ss beta, (ss gamma) and ss gamma, pathologically. These four subtypes were compared to cancerous invasion into the muscularis propria (pm-cancer) and cancerous invasion with serosal exposure (se-cancer). During the 10 years from 1979 to 1988, a total of 938 cases with gastric cancer were resected in the First Department of Surgery, Kurume University Hospital. Of these, 104 (11.1%) cases were ss-cancers, consisting of 28 (27%) cases of ss alpha, 33 (32%) cases of ss beta, 4 (3%) cases of (ss gamma) and 39 (38%) cases of ss gamma. Pm-cancers and ss-cancers were most frequently observed in Borrmann type 2, macroscopically, and in the differentiated type, histologically. On the other hand, se-cancers were frequently observed in Borrmann type 3 and in an undifferentiated type. Positive lymph node metastases were found in 49.1% of pm-cancers, in 50.0% of ss-cancers and in 79.9% of se-cancers (p < 0.01), with no statistical difference in the positive lymph node metastasis rates for the subdivisions of ss-cancer. In ss-cancer, however, there was a statistical difference in prognosis according to the tumor size, and according to the degree of subserosal infiltration. The 5-year survival rate was 82.3% for pm-cancer, 75.0% for ss-cancer and 34.7% for se-cancer (p < 0.01).

Female↗
PubMed2003

Hodgkin and non-Hodgkin lymphoma of the head and neck: clinical, pathologic, and imaging evaluation.

Lymphomas are subdivided into HL and NHL and are more specifically classified into subtypes of HL or NHL according to the WHO classification. HLs involve the lymph nodes predominantly and only approximately 5% arise in extranodal sites, whereas 30% of NHLs present in extranodal sites. Imaging studies, including CT and MR imaging, cannot distinguish [figure: see text] HL from NHL, and cannot differentiate their various subtypes, necessitating a pathologic diagnosis. Clinical parameters, however, can be helpful in differentiating the two broad categories of lymphomas, and subtypes of lymphomas have predilections for different sites within the head and neck. HL is most commonly located in the lymph nodes of the neck and mediastinum. Marginal-zone lymphoma has an affinity for the ocular adnexa, salivary glands, larynx, and the thyroid gland. Diffuse large B-cell lymphoma is commonly encountered in the paranasal sinuses, mandible, maxilla, and Waldeyer ring. Burkitt lymphoma occurs more frequently in children and young adults and frequently affects the maxilla and mandible, with a greater distribution of involvement at a lower frequency. On imaging studies, the lymph nodes of HL and NHL are homogeneous and variable in size, with an average diameter from 2 to 10 cm. They may enhance slightly to moderately, display necrosis before and after treatment, and display calcification post-treatment. NHL in extranodal sites in the head and neck (nasopharynx, Waldeyer ring, oral cavity, and larynx) manifests frequently as a submucosal mass accompanied [figure: see text] by polypoid, bulky masses with a smooth mucosal surface. Clinically aggressive lymphomas, such as Burkitt lymphoma, diffuse large B-cell lymphoma, and NK-/T-cell lymphomas are characterized by destruction of the maxilla, mandible, and bones around the paranasal sinuses, which is indistinguishable from bony destruction in other malignant tumors, such as SCC. Contrast CT is indicated for evaluation of cervical lymph nodes; the chest, including the mediastinum; the pelvic cavity; paranasal sinuses; and orbits. CT is also useful for detection of bone destruction involving the base of the skull, paranasal sinuses, and the mandible or maxilla. MR imaging is preferred for the assessment of extension of lymphomas to different fascial spaces (parapharyngeal, masticator, infratemporal fossa, tongue, and nasopharynx) and for intracranial extension. Lymphomas are isodense to muscle on CT and circumscribed with distinct margins that occasionally display extranodal extension with less-well-defined margins and areas of necrosis within the tumor matrix. Lymphomas appear low in signal intensity on T1-weighted images and low to high in signal intensity on T2-weighted images, with variable, but usually low, enhancement following introduction of Gadolinium-DTPA (Gd-DTPA) contrast material.

Head and Neck Neoplasms↗
PubMed2004

Liposarcoma subtypes: identification with computed tomography and ultrasound-guided percutaneous needle biopsy.

The purpose of the study was to evaluate the feasibility of image-guided percutaneous needle biopsy to enable specific subtype classification of liposarcoma in patients with previously diagnosed disease and compare the yield of fine and large needle techniques for each subtype. We reviewed the medical records and pathology reports of 69 fine (20 g) needle and large (15, 16 g) needle biopsies performed in 44 patients enrolled in a clinical trial evaluating the effect of a novel therapy for advanced liposarcoma in the abdomen and pelvis. Cytopathologists and surgical pathologists identified features that enabled them to classify the tumor into one of four subtypes: well differentiated, myxoid/round cell, pleomorphic and dedifferentiated. The pre-study open surgical biopsy was used as the standard for comparison. The diagnostic yield (proportion of biopsies with correct subtype diagnosis) of percutaneous biopsy for identifying all subtypes of liposarcoma was 81% (64% for fine needles and 73% for large needles alone). There was a significant association between pathologic subtype and the probability of a correct diagnosis (P=0.05). Accurate diagnostic subset classification of liposarcoma by percutaneous biopsy is feasible, although both fine and large needles should be used. Although these data cannot be extrapolated to primary diagnosis of liposarcoma, they are important for screening and subtyping of possible recurrence.

Adult↗
PubMed2006

[HSC transplantation-associated intestinal thrombotic microangiopathy: clinical pathological features, diagnosis criteria and treatment].

Thrombotic microangiopathy (TMA) is a lethal transplantation-associated complication which exactly likes acute intestinal graft-versus-host disease (GVHD) in the clinical manifestation. 373 consecutive patients with hematological diseases received family HLA matched or mismatched HCT from May, 2002 to July, 2004. To analyse the clinical and pathological characteristics of TMA, 30 patients who suffered from severe diarrhea and received colonoscopic examination and gut biopsy were retrospectively analyzed. The results indicated that 7 patients originally diagnosed as gut GVHD showed the pathological evidence of enteric TMA. The incidence of TMA was 7 out of 30 specimen (23.3%). Pathological evidence of enteric TMA shown microvascular disorder characterized by thrombus in the capillary without infiltration of lymphocytes and perivascular hemorrhages in the mucosa, swelling and focal denudation of epithelial cells. All patients with TMA were associated with cytomegalovirus (CMV) antigenemia/disease. Among these patients, 4 cases, who only showed TMA without the evidence of gut GVHD pathologically, displayed treatment-resistant bloody diarrhea, renal failure, veno-occlusive disease, hemorrhagic cystitis, hemolytic anemia as well as thrombocytopenia. But the other 3 cases, with co-existence of both TMA and GVHD pathological characteristics had better treatment response. Survival analysis indicated that 3 patients with TMA-GVHD survived for 461 to 536 days but three out of four TMA patients died from VOD with liver failure as well as multiple organ failure during 101 to 254 days after HCT. In conclusion, to better diagnose those patients with severe and refractory diarrhea following HCT, pathological examination may indicate crux evidence to identify intestinal TMA from gut GVHD. Furthermore, this primary report has first evidenced that TMA and TMA-GVHD are two pathologically well-recognized subtypes with the difference between the pathological characteristics, treatment response and clinical outcomes.

Graft vs Host Disease↗
PubMed1995

Characterization of axonal ultrastructural pathology following experimental spinal cord compression injury.

The present study characterizes axonal pathology associated with traumatic compression injuries of the spinal cord and quantitatively assesses subtypes of axonal pathology in the acute, post-injury period. Eighteen adult female Wistar rats underwent spinal cord compression injury with a 53 g modified aneurysm clip at the C8-T1 segment. Six additional rats served as sham controls. Six experimental animals were sacrificed at each of the three post-injury time points: 15 min, 2 h and 24 h. From all animals, the C8-T1 spinal cord was dissected and processed for both light and electron microscopy. Axonal pathology included periaxonal swelling, organelle accumulation, vesicular myelin, myelin invagination, myelin rupture, and giant axons. Early myelin rupture and the ultrastructural features of giant axons are described here for the first time in the context of spinal cord compression injury. The quantitative analysis characterizes the prevalence of types of axonal pathology over the acute post-injury period and provides evidence for the secondary injury hypothesis regarding the evolution of axonal pathophysiology following trauma.

Animals↗
PubMed2026

Diagnostic value of blood p-tau subtypes in Alzheimer's disease progression and pathology: systematic review and meta-analysis.

BACKGROUND: Alzheimer's disease (AD) is the most common neurodegenerative disease and the most likely to lead to dementia. With the availability of the latest therapies, the need for Alzheimer's disease diagnosis is now gradually increasing. Whereas blood phosphorylated-tau (p-tau) has demonstrated excellent performance in the prediction and diagnosis of disease progression and A&#x3b2; positivity in AD, there are differences between different p-tau subtypes. Therefore, a pooled analysis of different blood p-tau subtypes is of more important clinical value. METHOD: Relevant literature was screened by complete search in four databases, Pubmed, Embase, Cochrane Library and Scopus. Relevant data and AUC and their confidence intervals of the included literature were extracted and analyzed by classification according to p-tau subtypes. Quality assessment was performed using the QUADAS-2 tool. RESULT: Our results reveal that p-tau217 performs better in the diagnostic performance in most stages of AD, which is consistent with the guidelines. However, our results concluded that p-tau217 has poorer diagnostic performance in the stages of cognitive unimpaired or less cognitively impaired, especially in the A&#x3b2; positivity diagnosis of SCD and CU. Head-to-head meta-analyses formally confirmed that p-tau217 significantly outperforms p-tau181 across AD dementia, A&#x3b2; positivity, tau positivity, and biological staging (all P&#x2009;<&#x2009;0.05), whereas no significant difference was observed between p-tau231 and p-tau181. CONCLUSION: By integrating single-arm pooled AUC estimates with formal head-to-head statistical comparisons, our study provides evidence-based support for plasma p-tau217 as the subtype with the most robust diagnostic performance across AD pathology and biological staging. Head-to-head analyses formally confirmed that p-tau217 significantly outperforms p-tau181 in A&#x3b2; positivity, Tau positivity, and biological staging.

Humans↗
PubMed2000

MRI of the shoulder.

Shoulder imaging is one of the major applications in musculoskeletal MRI. In order to analyze the images it is important to keep informed about anatomical and pathological findings and publications. In this article MRI technique, anatomy and pathology is reviewed. Technical considerations about MR sequences and examination strategy are only shortly discussed with emphasis on turbo spin echo and short T1 inversion recovery imaging. Basic anatomy as well as recent findings, including macroscopic aspects of the supraspinatus fat pad, composition of the supraspinatus muscle belly, and variability of the glenohumeral ligaments or coracoid ligament, are presented. Basic pathological conditions are described in detail, e. g. instability particularly problems in differentiating the various subtypes of labral pathology. Rotator cuff diseases are elucidated with emphasis on some rarer entities such as subscapularis calcifying tendinitis, coracoid impingement, chronic bursitis producing the double-line sign, prominent coraco-acromial ligament and the impingement due to an inflamed os acromiale.

Acromioclavicular Joint↗
PubMed2006

[Clinical features of 89 patients with primary non-Hodgkin's lymphoma of the tonsil].

BACKGROUND & OBJECTIVE: Head and neck lymphoma develops predominantly in the tonsil. This study was to investigate the clinical features of primary non-Hodgkin's lymphoma (NHL) of the tonsil, and to explore possible ways to improve the prognosis and quality of life of the patients after treatment. METHODS: Clinical data of 89 naive patients with NHL of the tonsil, treated from May 1990 to Jan. 2003, were retrospectively reviewed. All patients were confirmed pathologically and classified according to revised European-American Lymphoid Neoplasms and World Health Organization Classification, and staged according to the Ann Arbor classification. Stage I-II patients received radiochemotherapy-predominant treatment, whereas stage III-IV patients received chemotherapy-predominant treatment. RESULTS: Of the 89 cases, 60 (67%) were diffuse large B-cell subtype, 11 (12%) were peripheral T-cell subtype, 5 (6%) were indolent lymphoma, 1 was anaplastic large T-cell lymphoma, and 1 was T lymphoblastic lymphoma; 81 (91%) were stage I-II disease. Of the 89 patients, 58 (72%) received radiochemotherapy, 19 (21%) received radiotherapy alone, 3 received chemotherapy alone, and 1 received radiochemotherapy combined with rituximab. The 5-year overall survival rate was 80%, that of stage I-II patients was 84%. Cox regression multivariate analysis showed that the survival rate was correlated to the value of international prognostic index (IPI), and whether the patient had primary refractory or relapsed disease, but was not correlated to sex, age, pathologic subtype, B symptoms, and bulky disease. CONCLUSIONS: Most patients with NHL of the tonsil are at early stages, with good prognosis. Diffuse large B-cell lymphoma is the most common pathologic subtype. Primary refractory, relapse, and IPI>1 are independent prognostic factors.

Adolescent↗
PubMed2005

[Correlation between pathology and image characteristics of retroperitoneal liposarcoma].

OBJECTIVE: To investigate the correlation between the pathological and image features of different subtypes of retroperitoneal liposarcoma. METHODS: Pathological and image characteristics of 21 retroperitoneal liposarcomas were retrospectively analyzed comparing their different histopathological subtypes. RESULTS: This series consisted of 11 well-differentiated, 4 myxoid, 3 round-cell, 2 pleomorphic and 1 dedifferentiated liposarcoma. Well-differentiated liposarcomas were predominantly composed of lipoma-like and sclerosing components. On CT and MRI image, the attenuation and signal intensity of lipoma-like components resembled those of fat, whereas the signal intensity of sclerosing components was similar to those of muscle. Unenhanced CT image of the myxoid subtype showed density resembling that of water. On contrast-enhanced CT image, it showed gradual reticular or sheet-like enhancement. The CT and MRI image appearance of the round cell and pleomorphic subtypes resembled those of nonfatty soft tissue masses with foci of necrosis. The dedifferentiated liposarcoma showed the image feature of a well-differentiated component clearing enhanced soft tissue mass. CONCLUSION: Different subtypes of retroperitoneal liposarcoma show different CT and MRI features relating to their major histologic components. A good understanding of the relation between their radiological and pathological features is helpful to arrive at a correct diagnosis for retroperitoneal liposarcoma.

Adult↗
PubMed2007

Risk factor profile of cerebral small vessel disease and its subtypes.

BACKGROUND: The mechanisms of cerebral small vessel disease (SVD) are unclear. Both atherosclerosis and a non-atherosclerotic diffuse arteriopathy have been reported pathologically. Two pathological and radiological subtypes have been suggested: localised atherosclerotic disease in larger perforating arteries causing larger lacunar infarcts without leukoaraiosis, and diffuse disease in smaller arterioles causing multiple smaller lacunar infarcts with leukoaraiosis. If atherosclerosis were important in SVD as a whole or in one particular subtype, one would expect the risk factor profile to be similar to that of cerebral large vessel disease (LVD). METHODS: Risk factor profiles were compared in Caucasian stroke patients with SVD (n = 414), LVD (n = 471) and 734 stroke-free Caucasian population controls. Patients with SVD were subdivided according to the presence or absence of confluent leukoaraiosis, into isolated lacunar infarction (ILI) and ischaemic leukoaraiosis (ILA). RESULTS: Hypertension was commoner in SVD than LVD (odds ratio (OR) 3.43 (2.32 to 5.07); p<0.001) whereas hypercholesterolaemia (OR 0.34 (0.24 to 0.48); p<0.001), smoking (OR 0.63 (0.44 to 0.91); p = 0.012), myocardial infarction (OR 0.35 (0.20 to 0.59); p<0.001) and peripheral vascular disease (OR 0.32 (0.20 to 0.50); p<0.001) were commoner in LVD. Among SVD patients, age (OR 1.11 (1.09 to 1.14); p<0.001) and hypertension (OR 3.32 (1.56 to 7.07); p = 0.002) were associated with ILA and hypercholesterolaemia (OR 0.45 (0.28 to 0.74); p = 0.002), diabetes (OR 0.42 (0.21 to 0.84); p = 0.014) and myocardial infarction (OR 0.18 (0.06 to 0.52); p = 0.001) with ILI. CONCLUSION: SVD has a different risk factor profile from the typical atherosclerotic profile found in LVD, with hypertension being important. There are differences in the risk factor profile between the SVD subtypes; the association of ILI with hypercholesterolaemia, diabetes and myocardial infarction may be consistent with a more atherosclerotic aetiology.

Aged↗
PubMed2004

Synchronous gastrointestinal and musculoskeletal manifestations of different subtypes of inflammatory myofibroblastic tumor: CT, MRI and pathological features.

We describe a case of an unusual multicentric appearance of an inflammatory myofibroblastic tumor, consisting of multiple gastrointestinal masses with different growth patterns and simultaneous, distant, musculoskeletal manifestations. CT and MR imaging features demonstrated a different degree of lesion enhancement, which proved histologically to be related to an alternation of predominantly spindle cell areas with a myxoid-vascular IMT subtype. A clear separation of the imaging characteristics of this tumor's subtypes by correlation with the pathology was not possible because of the mixed histologic character of the tumor in all its locations. However, MRI signal in the T2-weighted sequence was lower in the spindle cell variant localized predominantly in the musculoskeletal system, while the gastrointestinal predominantly myxoid-vascular counterparts showed slightly higher signal in the T2-weighted sequence.

Aged↗
PubMed1981

Multiple histologic subtypes of non-Hodgkin's lymphoma: clinical and pathologic features.

Twenty patients with non-Hodgkin's lymphoma (NHL) had different histologic subtypes of NHL in multiple sites or in a single tumor mass either at the time of their initial biopsy and staging (13 patients) or in the course of their disease (seven patients). These 20 cases represent 3.7% of all patients with NHL seen at the University of Chicago between January 1968 and May 1979. The five-year actuarial survival rate for all 20 patients was 68%. For those 13 patients who had multiple histologic subtypes at the initial workup, the five-year survival rate was 45%; for the seven patients who developed a new histologic subtype later in the course of the disease, the five-year survival rate was 85%. In the latter group of patients, however, the initial biopsy specimens demonstrated better prognostic subtypes, and the median survival from the time of diagnosis of a new, less favorable histologic subtype averaged only four months. These findings indicate that the prognosis is related to the least favorable histologic subtype present, unless this is only a minor component of a composite lymphoma or is limited to one extranodal site.

Adult↗
PubMedDate not supplied

Glutamate receptor binding in the human hippocampus and adjacent cortex during development and aging.

Distinct patterns of age-related alterations in NMDA (MK801 binding) and non-NMDA, AMPA (CNQX), and kainate binding have been identified in human hippocampus and parahippocampal gyrus in normal individuals with no evidence of degenerative brain disease ranging in age from 24 gestational weeks to 94 years. Whereas MK801 binding did not alter substantially over this age range, CNQX binding rose from low levels in the fetus to maximum levels between neonate and middle age, and kainate binding declined extensively from the perinatal to adult stage. Following maturity, there were no significant changes in kainate binding, although MK801 binding increased in CA1 and CA3 and CNQX binding declined in several regions, particularly CA2 and subiculum. For each receptor binding the timing of these fluctuations ocurring during development and aging varied within different regions of the dentate gyrus, hippocampus proper, subicular complex, and entorhinal cortex examined. The transient peaks of receptor binding are likely to reflect processes of synaptogenesis and pruning and may provide clues regarding the role of the different glutamate receptor subtypes in various pathologies of the hippocampus and adjacent cortex associated with developmental disorders (of genetic origin or due to perinatal trauma or insult). The absence of substantial changes in any subtype examined from middle to old age suggests alterations in transmitter binding to these glutamate receptors are not involved in senescent neurodegeneration.

Adolescent↗
PubMed2004

The importance of timing of adrenergic drug delivery in relation to the induction and onset of adjuvant-induced arthritis.

Stressful events often precede onset and exacerbate established rheumatic diseases. There are numerous reports of abnormal autonomic function in rheumatoid arthritis (RA) patients. Targeting the sympathetic nervous system (SNS) with adrenergic receptor (AR) drugs in RA patients and animal models of the disease have revealed mixed results, with treatments inhibiting and exacerbating disease pathology. We tested the hypothesis that variability in disease outcome following adrenergic drug treatment is due to different roles played by the SNS at different disease stages. The contribution of beta2- and alpha-AR subtypes to disease pathology was studied at different disease stages in adjuvant-induced arthritis (AA), an animal model of RA. Lewis rats were given twice-daily intraperitoneal (i.p.) injections of an alpha-AR antagonist (phentolamine: 500 microg/kg) or a beta2-AR agonist (terbutaline: 1200 microg/day), initiated at adjuvant challenge or disease onset, and continued through severe disease. Both adrenergic therapies, when initiated at adjuvant challenge exacerbated disease pathology. In contrast, SH1293, an adrenergic drug that targets both alpha- and beta-AR (300 microg/day; twice-daily), initiated at adjuvant challenge did not exacerbate disease severity. Additionally, the same treatment regimen of phentolamine, terbutaline or SH1293 initiated at disease onset attenuated joint-inflammation and dramatically reduced bone destruction in the arthritic hind limbs. These data support the SNS playing different roles in disease pathology preclinically and after disease onset. Given current drug therapies are not effective in preventing bone destruction, these data support using adrenergic drugs as bone sparing treatments in RA.

Adrenergic Agents↗
PubMed1992

Subtypes of acute postinfectious glomerulonephritis: a clinico-pathological correlation.

The case records and histopathology of 42 adults with the characteristic light and electron microscopic features of Acute Postinfectious Glomerulonephritis (APGN) were studied. The biopsies were divided into three subtypes depending on the form and distribution of subepithelial "humps" and other immune-complex deposits on electron microscopy (EM): the "starry sky", "garland" and "mesangial" patterns. There was no significant difference between the three subtypes with regard to age, hypertension, creatinine, anti-streptolysin 0 titer and low serum complement levels on presentation. The "garland" subtype had significantly more proteinuria than both the "starry sky" (p = 0.04) and "mesangial" (p = 0.003) subtypes. The "mesangial" pattern had a lesser degree of cellular proliferation and leukocytosis in the glomeruli than the other subtypes. The "starry sky" subtype was present in 4 of the 5 cases of crescentic nephritis and in 6 of the 7 patients with a chronic course. Our study suggests that the higher degree of proteinuria in the "garland" subtype and the chronic course of the "starry sky" subtype are the main clinical features that distinguish the three histological subtypes. Our patients, from a developing community with poor socio-economic conditions, had a poor prognosis.

Acute Disease↗
PubMed1997

Comparison of risk factors for lacunar infarcts and other stroke subtypes.

BACKGROUND: Lacunar infarction (LI) is an ischemic stroke subtype with unique clinical, radiological and pathological features. Its relation to other stroke subtypes is unclear. To better understand the underlying pathological process of LI, we compared the risk factors of LI with those of other stroke subtypes. METHODS: During the study period (from January 1, 1990 to December 31, 1991), 240 consecutive patients with first-ever strokes admitted to the stroke unit of our hospital were enrolled to the study and were classified into one of the four stroke subtypes (52 with LI, 80 atherothrombotic infarcts, 38 cardiogenic embolism and 70 brain hemorrhage) based on their computed tomography (CT) and clinical features using the guideline developed by the National Institute of Neurological Disorders. Eighty outpatients of similar age who had either low back pain or cervical spondylosis were recruited from the clinics of Neurology to serve as non-stroke controls. Data collected included demographics, lifestyle, and other vascular risk factors. Detailed physical and neurological examination, blood biochemistry and Doppler ultrasound on cervical vessels were performed. RESULTS: Our investigations revealed that LI is a common stroke subtype accounting for 21% of all first-ever strokes in our hospital. Like ischemic stroke patients, those with LI were much more likely to have hypertension, diabetes, heart disease and carotid disease when compared with non-stroke controls. Patients with brain hemorrhage had less history of diabetes and lower levels of cholesterol than LI patients. CONCLUSIONS: LI patients seemed to share more risk factors with ischemic stroke patients than with brain hemorrhage patients. These shared risk factors suggest a possibly similar underlying pathological process between ischemic strokes and LI patients. Careful screening for those risk factors should be part of the mandatory clinical management for the prevention of LI.

Aged↗
PubMed2003

Follicular lymphoma lacking the t(14;18)(q32;q21): identification of two disease subtypes.

The clinical and pathological features, including karyotype data and BCL2 protein expression pattern, of follicular lymphoma without a t(14;18)(q32;q21) have not been well defined. We have identified and conducted a detailed analysis of 50 cases with follicular lymphoma who lack the t(14;18). Fluorescent in situ hybridization (FISH) analysis was used to exclude cases with a cryptic IGH/BCL2 rearrangement. BCL2 protein expression level was assessed by immunohistochemistry. The karyotypes were assessed for recurrent sites of structural rearrangement, duplications and deletions on a band-by-band basis, and compared with a large cohort of cases with t(14;18). A distinct pattern of chromosomal alterations was identified in the cases without t(14;18). BCL2 protein overexpression was detected in 33% of 49 tested cases. In this minority, the karyotypes frequently showed increased copies of chromosome 18. The majority of cases (67%) did not show BCL2 overexpression and were characterized prominently by the presence of t(3;14)(q27;q32), implying a role for BCL6. Follicular lymphomas that lack a t(14;18) were segregated into two subgroups with distinct cytogenetic, phenotypic and possibly clinical features: one with BCL2 protein overexpression not related to an IGH/BCL2 rearrangement and a second without BCL2 overexpression. Objective identification of BCL2 expression level as well as BCL2 and BCL6 status by cytogenetic or FISH analysis has potential clinical utility and may yield insights into alternative genetic mechanisms associated with B-cell lymphomas with a follicular growth pattern.

Adult↗