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The classification of neuroendocrine (NE) lung tumors has been revised in the 1999 World Health Organization (WHO) classification of lung tumors, allowing sharp morphological definition of typical versus atypical carcinoids, and atypical carcinoids versus large cell neuroendocrine carcinoma (LCNEC), a newly described class of high-grade NE lung tumors which differs from small-cell lung cancer by a large-cell phenotype. Divergent differentiation accounts for the high frequency of glandular differentiation with mucin production, and ultrastructural features in carcinoids and LCNEC, and low frequency of squamous differentiation in both LCNEC and SCLC. Specific NE markers (chromogranin, synaptophysin, neural cell adhesion molecule) and epithelial markers consistently negative in neuroendocrine components (cytokeratins 1, 5, 10, 14; epidermal growth factor (EGF)-receptor, human leukocyte antigen beta 2 (HLA-beta2) microglobuline) help to recognize divergent differentiation in NE tumors. At morphological level, divergent differentiation in NE tumors is recognized in WHO classification as variants: combined SCLC and combined LCNEC. The derivation of all lung tumors from a common endodermal stem cell and adoption of amine precursor uptake and decarboxylation properties by this endodermal stem cell explains divergent differentiation in NE lung tumors and the occurrence of NE subsets in NSCLC.
This article provides us with background information on the disease. Clinical features, variants and classification, laboratory findings, and pathology are discussed. Knowledge of the disease's pathogenesis has increased recently and specific causes discussed are predisposing factors, triggering agents, endothelial damage, defective PGI2 bioavailability, FVIII/vWF multimeric structure abnormalities, platelet activation, and hemolytic anemia. Proposed specific therapies discussed are steroids, heparin, antiplatelet agents, prostacyclin, splenectomy, immunosuppressive agents, plasma infusion, and plasma exchange.
An electron-microscopic study was made of carcinoids, malignant carcinoids and small-cell lung cancer. These neoplasms are shown to represent one histogenetic group--neuroendocrine tumours (apudomas) of the lung. One can distinguish 3 main structural forms among them, i.e. epithelioid, sarcoma-like and symplastic. According to the ultrastructural criteria the neoplasms mentioned can be classified by their differentiation degree, as well, intermediately and poorly differentiated variants. This classification correlates well enough with the catamnesis of patients and may serve for prognosis of the disease.
Problems in the diagnosis and treatment of cysto-sarcoma phyllodes in thirteen women are discussed. This is a rare breast tumour which must be regarded as semi-malignant. Its malignancy consists of its tendency to recurrence and the development of distant metastases. Five patients had one or more recurrences and three patients had metastases which were fatal. Radiological and thermographic diagnosis of small tumours is unreliable. It is not possible to distinguish the benign from the malignant variants. Accurate classification depends on histological examination. The authors consider removal of the glandular tissue or simple mastectomy to be the best form of treatment.
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Much of the interest in frostbite has arisen from various military experiences including the Korean war, World War II, and Napolean's battles in Russia and Poland. Historically frostbite has been not only a military problem, but also a problem in high-altitude climbers and the more recently investigated homeless population. However, the physician should not disregard frostbite as only victimizing the poor and indigent. Anyone who is exposed to harsh winter conditions over a long period of time can suffer from frostbite. Many milder cases of frostbite presented to Cook County Hospital in Chicago were simply due to prolonged winter exposure when a motorist's care broke down. The authors present a review of the variants, pathophysiology, classifications, predisposing factors, and treatment of frostbite. Five cases of frostbite will also be presented from Cook County Hospital in Chicago, IL.
Because of the nucleotide sequence diversity of different isolates of hepatitis C virus, it has become important to clarify whether distinct genotypes of hepatitis C virus vary with respect to pathogenicity, infectivity, response to antiviral therapy and geographic clustering. We assessed nucleotide sequence variability in the 5' noncoding region of hepatitis C virus, using restriction enzymes to analyze the distribution of hepatitis C virus genotypes, in 80 patients with chronic hepatitis C virus infection. Genotypes were correlated with demographic, clinical and histological features. Thirty-seven patients were infected with type 1, 10 had type 2 and 8 had type 3, and another 23 were infected with a new distinct hepatitis C virus type now classified as type 4. Two were infected with variants whose classification are uncertain. Types 1, 2 and 3 were found in patients from the United Kingdom, southern Europe, Asia, Africa and South America. Nineteen of 23 type 4 genotype isolates were from Middle Eastern patients, compared with 0 of 37 type 1 isolates (p < 0.001). Of 21 Middle Eastern patients, 19 (90.4%) had type 4 hepatitis C virus (p = 0.001, odds ratio = 9). We found no significant difference between the mean ages or mean serum aminotransferase concentrations between the various types. Types 1, 2, 3 and 4 were found in patients with mild-to-moderate disease or severe disease. However, 21 of 29 (72.4%) patients with type 1 who underwent liver biopsy had severe chronic hepatitis, cirrhosis or hepatocellular carcinoma histologically; 8 had mild or moderate chronic hepatitis without cirrhosis (p = 0.03, odds ratio = 2.6).(ABSTRACT TRUNCATED AT 250 WORDS)
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Combinations of arterialized flaps with other grafts have to be used for repair of extensive perforating defects caused by removal of local disseminated malignant tumors of the head and neck. A total of 635 plastic surgeries were carried out during the latest 15 years at Department for Tumors of the Upper Respiratory Tract, Cancer Research Center, Russian Academy of Medical Sciences. Of these, combined plasty was carried out in 79 cases; in 28 patients the tumor was localized in the median area of the face, in 37 in the lower part, and in 14 on the neck. Primary combined plasty was carried out in 41 patients, delayed repair in 38. Musculocutaneous flaps were used in 42 cases, fatty-cutaneous ones in 37. A working schematic classification of variants of primary and delayed combined plasty in patients operated on for tumors of the head and neck has been developed.
It is controversial if the rare dermoid cyst of the testis should be classified as a variant of mature teratoma or separately. The spectrum of findings is also ill defined, as is the relationship of dermoid cyst to intratubular germ cell neoplasia of the unclassified type (IGCNU). This study therefore reports the findings in five testicular dermoid cysts that occurred in five patients, 17-42 years of age, who presented with testicular masses. Four lesions consisted of a keratin-filled cyst with a thickened wall, whereas one had islands of "shadow" squamous epithelial cells with superimposed calcification and ossification (pilomatrixoma-like variant). Hair was identified grossly in two cases. On microscopic examination, four tumors had hair follicles with sebaceous glands showing a typical, cutaneous-type orientation to an epidermal surface, although no hair shafts were present in two. In addition, the fibrous wall contained smooth muscle bundles (all tumors) and eccrine or apocrine sweat glands (4 tumors). In some cases there were also glands lined by ciliated epithelium (4 tumors, including the pilomatrixoma-like variant), intestinal mucosa (1 tumor), and bone (2 tumors). There was no cytologic atypia or apparent mitotic activity, and no case had IGCNU in the seminiferous tubules. All patients were clinical stage I and were treated by orchiectomy without adjuvant therapy. All were well on follow-up from 1.5 to 9.5 years later. This study supports that dermoid cyst may have noncutaneous teratomatous elements and that an important criterion for its diagnosis is the absence of IGCNU. It also supports that it should be categorized separately from mature testicular teratoma because of the malignant nature of the latter in postpubertal patients. These observations suggest that there are at least two pathways for testicular teratomas in postpubertal patients: the more common being through IGCNU by differentiation from an invasive malignant germ cell tumor and the less common one, taken by dermoid cyst, by direct transformation from a nonmalignant germ cell.
Several variant alleles of the HumD21S11 locus have only been reported in Australasian population samples. Fifteen such alleles were observed in Caucasian and Australian Aborigine sub-population databases compiled from residents of the state of Western Australia. Each variant was sequenced to authenticate the allelic designation and determine the structural conformation. Nine novel structural variants are described. The structure of the repeat region of these rare alleles combined with the STR designation brings aspects of the HumD21S11 nomenclature guidelines into question, in particular the designation of common incomplete repeats (or "0.2's"). The conformation of the sequences provides evidence in support of a genetic relationship between the Australian Aborigine and the Papuan people.
23 patients with hemophilia B have been investigated by means of several immunological methods. 16 patients (69.9%) had no detectable factor XI antigen. Five had a normal factor IX antigen and the electrophoretic mobility of this abnormal factor IX was similar to that of its normal counterpart. One of these five patients had hemophilia Bm, since ox brain thromboplastin clotting time was severely prolonged. The remaining two patients had reduced or decreased factor IX antigen. Several patients showed a slight protongation of ox brain thromboplastin time due to an associated slight factor VII deficiency. On the basis of these results, a tentative classification of hemophilia B into five variants is proposed, namely: hemctor IX antigen; hemophilia Bra, or with reduced factor IX antigen; hemophilia Bm, or with normal factor IX antigen and severely prolonged ox brain thromboplastin; hemophilia B patients is feasible only by means of a battery of tests, namely:factor IX activity assay, factor IX antigen determination, ox brain thromboplastin clotting time, factor VII activity assay.
BACKGROUND: Classification of heterozygous germline PTEN variants in patients with, or suspected of having, PTEN hamartoma tumour syndrome (PHTS) remains challenging. Accurate classification is essential as these patients require lifelong cancer surveillance. METHODS: We identified all patients with a PTEN variant previously classified as a variant of uncertain significance (VUS), likely pathogenic (LP) or pathogenic (P), collected clinical data and reclassified all variants using the latest PTEN gene-specific American College of Medical Genetics (ACMG) guidelines. Moreover, genotype-phenotype correlations were assessed. RESULTS: 167 patients from 112 families were enrolled. Eighty-seven unique PTEN variants were identified, including 20 novel variants. After applying the PTEN gene-specific ACMG guidelines, 32 variants (36.8%) were reclassified, resulting in 60 PTEN variants classified as LP/P (69.0%), 18 variants classified as VUS (20.7%), while 9 variants were classified as LB/B (10.3%). Genotype-phenotype correlation was performed among 104 patients with LP/P variants: 51 cancer cases were recorded in 41 patients and a distinct PHTS phenotype was observed in 25% of patients, with macrocephaly being present in 99% of patients with a known head circumference. Twenty-three patients had neurodevelopmental delay and/or autism, and we observed an increased prevalence of missense variants in these patients. CONCLUSION: We identified 87 different PTEN variants, and application of PTEN gene-specific ACMG guidelines led to reclassification of 32 variants (36.8%), underscoring the importance of regular variant reassessment using the most recent gene-specific guidelines, ensuring optimal patient management and surveillance.
We have studied the detection and classification of genetic variants of human serum albumin by electrophoresis. Samples from 10 patients who were heterozygous for eight different albumin variants were studied by two methods. In agarose gel electrophoresis, each of these variants has an abnormal mobility and can be classified on the basis that structural changes at the N-terminus abolish 63Ni binding. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole serum, glycosylated variants are easily detected because of their greater apparent molecular mass.
A modified variant of the functional classification of patients with ischemic heart disease standard for all stages of rehabilitation is suggested. It is based on the rate with which the program of treatment is fulfilled and on the determination of the clinico-functional parameters and the physiological reaction of the patient during rehabilitation. The classification was tested on 98 patients with macrofocal myocardial infarction (average age 53.5 years) who underwent a successive rehabilitation program at the inpatient, sanatoria, out-patient stages with a subsequent two-year follow-up as out-patients after they had resumed working. The classification proved sufficiently informative in regard to the prognostication of the restoration of working capacity and the character of the course taken by ischemic heart disease.
Investigation of lymphogranulomatosis process in 42 patients included histological examinations of chains of lymph nodes with varying duration of their involvement. Lymphogranulomatosis was shown to begin with focal involvement of lymph nodes. The specific focus is initially located in the paracortical zone, then the pathological process extends into the medullary zone and finally into the cortical zone. As early and finally into the cortical zone. As early as the focal lesions occur the cell composition already corresponds to one of histological variants of lymphogranulomatosis (by Lukes' classification). No transition from variants with lymphoid prevalence to those with lymphoid exhaustion in groups of removed lymph nodes from the same patient was observed indicating independent development of each histological type and its stability for a given patient. No correlation between the clinical stage and morphological type of lymphogranulomatosis was established.
Histological and cytological preparations of the lymph nodes, spleen, bone marrow and other tumors from 140 patients with different variants of lymphosarcomas were subjected to a comparative clinicomorphological analysis. The data obtained were correlated to the WHO classification and the working formulation of non-Hodgkin's lymphomas intended for clinical use. It has been found desirable that the working formulation may be used for predicting the disease course and elaboration of the programs of lymphosarcoma treatment.