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In the interval 1962-1987 the author had treated 41 cases of giant cell bone tumors (25 females and 16 males). The 20-40 age group was prevalently affected (32 cases). The upper epiphysis of tibia and lower epiphysis of femur were the most common sites (13 and 9 cases, respectively). The clinical, x-ray and especially the histological data decided the type of intervention.
The paper is devoted to a study of the structure of subpopulations of 3 experimental tumors (ascitic Ehrlich carcinoma, melanoma B-16 and Lewis lung adenocarcinoma) in their progression and following single local X-radiation. At the same time some functional indices of cell viability were investigated over time: intracellular pH, intensity of respiration, the level of cell protein, the level of lipid peroxidation (according to the content of one of its end-products--malonic dialdehyde). Considerable differences of subpopulations within one tumor and between different tumor types were established. The relationship of functional differences of these subpopulations with the clonogenicity of forming cells was shown. X-radiation caused inhomogeneous changes in the structure of subpopulations, the above indices changed. The authors have analyzed the regularity of these changes, their relationship with radiosensitivity or radioresistance of tumor cell subpopulations.
A case of pituitary carcinoma is here presented, together with a review of the 25 cases so far reported in the literature. After a long-standing history of Cushing's disease, treated with interstitial pituitary irradiation and total adrenalectomy, Nelson's syndrome developed due to a pituitary neoplasm that finally spread through the subarachnoidal space, bringing the patient to death. The possible long-term role of surgery and radiotherapy in switching an aggressive behavior is also discussed.
A sporadic case of neurofibromatosis type 2 in a 23-year old woman is described with clinical and neuroimaging (CT or MRI) 4 years follow-up. Together with bilateral acoustic tumours multiple intracranial tumours and solitary orbital meningioma were present, the latter being confirmed surgically and histopathologically. Ocular findings of congenital cataract but lack of other external stigmata of neurofibromatosis completed the clinical picture of the disease. Diagnostic criteria of NF2, difficulties in establishing the optimal management options are described and the importance of evaluating of family members is underlined. Neuroimaging pictures showed tumour expansion over 4 years leading to severe disability with total blindness, deafness, paresis and cerebellar syndrome.
Treatment with Corynebacterium parvum (C. parvum) produces a significant prolongation of survival time of Lewis tumor bearing animals and reduces strikingly the incidence of pulmonary metastasis in syngeneic C57Bl/6 mice. On the other hand, treatment with Imuran, a known immunodepressive agent, reduces survival time and facilitates metastatic dissemination in the same model.
The authors discussed the effects of nuclear accident from Chernobyl (1986) upon the histotypes of cerebral glial tumors, first diagnosed during 1981-1991 at the Department of Pathology, Neurosurgical Hospital, Iaşi. It's microscopic diagnosis was determined according to the World Health Organization criterion (1979). The investigations established a tendency to diminish the incidence of astrocytomas and to increase the oligo-astrocytic tumors number, after 1986. Malignant astrocytomas did not presented any modifications with statistical significance during the eleven studied years.
First, chemotherapy was used to reduce metastatic tumours. Then, instead of a limited number of antimitotic agents, it permited to increase both the number of complete remissions and the survival ratio, mostly in embryonal tumours and lymphomas. The essential purpose of chemotherapy is to kill occult metastases. Combination chemotherapy using many agents with differing modes of action took place of monochemotherapy. In sophisticated schedules, drugs are given intermittently, to synchronizing treatment with the tumour doubling time and the recovery of normal rapidly dividing tissues. Unhappily, its use remains empiric, according to uncertainty about tumoral cell kinetic and modes of drugs action. Immediate toxicity of aggressive schedules prescribe to realize them in specialized pediatric centres. At last, in the future, it will not be enough to cure infantile cancer, but to allow children to live with less sequelae than to day.
PURPOSE: The aim of this study was to examine the association between E-cadherin expression and markers of Wilms' tumor aggression, including metastasis and recurrence. METHODS: Forty Wilms' tumor samples from the National Wilms' Tumor Study Group underwent immunohistochemical staining for E-cadherin. Tumor stage at diagnosis, recurrence, and loss of heterozygosity at 16q status was known for each of the tumor samples. E-Cadherin cell staining was defined as high (>33%) or low (<33%), and values were assigned by a pathologist blinded to the tumor characteristics. Five stage IV tumors were ineligible for assay because of lack of a tubular component. To identify a mechanism of downregulation, we screened tumor DNA for genetic mutations in exons 1-16 using a combination of WAVE and sequence analysis. To assess the functional significance of the identified mutations, the authors compared amino acid homology across multiple species. Finally, they performed reverse transcriptase-polymerase chain reaction for those tumors with intronic single nucleotide polymorphisms (SNPs) to evaluate for mRNA splice variants. RESULTS: Wilms' tumors presenting with metastatic (stage IV) disease demonstrated decreased levels of E-cadherin expression compared with localized tumors (stage I) (Fisher's Exact test, P < .01). In a search for the mechanism of the downregulation of E-cadherin, we identified 5 different mutations in 7 high stage tumors (7/15) and 1 mutation in a low stage tumor (1/20). The mutations occurred in amino acids that were conserved across multiple species. Additionally, 11 of 15 high stage tumors contained an intronic SNP located within 6 bp of the 5 intronic splice junction immediately downstream of exon 1. However, examination of 5 of these tumors using reverse transcriptase-polymerase chain reaction showed that this intronic SNP does not appear to disrupt the assembly of full-length E-cadherin transcripts. Lastly, no correlation was identified between E-cadherin expression and recurrence of disease. CONCLUSIONS: In this study, the authors have found an association between decreased E-cadherin expression and metastatic Wilms' tumor. Mutations identified may help identify a mechanism for downregulation. The functional significance of these mutations is supported by the conserved nature of the amino acids across multiple species. The authors believe these findings support the involvement of E-cadherin in the evolution of Wilms' tumor.
Natural selection occurs at multiple levels of organization in cancer. At an organismal level, natural selection has led to the evolution of diverse tumor suppression mechanisms, while at a cellular level, it favors traits that promote cellular proliferation, survival and cancer. Natural selection also occurs at a subcellular level, among collections of cells and even among collections of organisms; selection at these levels could influence the evolution of cancer and cancer suppression mechanisms, affecting cancer risk and treatment strategies. There may also be cancer-like processes happening at different levels of organization, in which uncontrolled proliferation at lower levels may disrupt a higher level of organization. This Essay examines how selection operates across levels, highlighting how we might leverage this understanding to improve cancer research, prevention and treatment.
The AA. examine the possibilities of the present imaging to the diagnostic definition of the extensive and destructive forms of the Central Giant cells Tumor of the maxilla. The CT and MR studies are compared with conventional x-Ray. The analysis performed evinces, besides the well-known semeiological CT superiority for the evidence of the osseous erosions, the ability to follow by MR imaging the evolution of the tumor, in the its relationships with the fascial, muscular, adipose and fibromucous soft tissues, when it exceeds the osseous barrier of the maxillofacial skeleton, enclosed therein the palatal plane.
Most neoplasias of lymphoid and other hematopoietic cells in commercial poultry are caused by viruses which belong to one of four distinct groups. Marek's disease virus (MDV) is an oncogenic herpesvirus. Avian leukosis virus (ALV), reticuloendotheliosis virus (REV) and lymphoproliferative disease virus (LPDV) are oncogenic retroviruses. Each group is distinguished by nucleic acid type, molecular structure, antigenicity, epidemiology, host range and other characteristics. However, most of these viruses have in common a unique ability to persist, both in the host and in the ecosystem. In addition, both the viruses and the virus-host relationships for several members of the group have demonstrated a propensity to evolve with time, creating new dilemmas for diagnosis and control. A focus on the persistence and evolution of avian tumor viruses will be used to address a number of current issues with individual viruses of economic importance. Issues of primary concern include (1) the evolution of MDV towards greater virulence with concomitant reduction of vaccine efficacy and expansion of host range, (2) the emergence of subgroup J ALV as a major pathogen in meat-type breeder stocks, and (3) the increasing prevalence of REV and its evolving role as a pathogen in chickens and turkeys.
The A, B, H blood group antigens can be detected in normal transitional epithelium of the urinary bladder by the red cell adherence (RCA) test. We examined the possibility that the reactivity for these antigens is lost or decreased in transitional cell carcinomas and that such a change may reflect the future evolution of these tumors. We studied several bladder biopsies from 60 patients who presented with noninvasive transitional cell carcinomas and were followed for at least 5 years or until muscle invasion was histologically demonstrated. Eighty-one percent of patients whose tumors were RCA positive in the initial biopsy did not subsequently develop invasive tumors and 27% of these patients had no recurrences. All 34 patients whose tumors were negative in the initial biopsy experienced recurrences and 62% of them developed invasive lesions. In 81% of patients, the recurrent tumors retained the same pattern of RCA reactivity for blood group antigens on serial biopsies. These results suggest that the presence of readily detectable A, B, B antigens correlates with a favorable prognosis whereas their absence denotes an aggressive potential.
Five patients are reported who underwent X-ray epilation in childhood for tinea capitis and who developed meningiomas after about four decades. X-ray irradiation resulted in permanent alopecia in four of the five patients. In four patients the tumors were found on the convexity, one patient had a tuberculum sellae meningioma. All five patients underwent surgery. Recurrence was noted in three of the five patients, one of them was reoperated. No malignant features, but signs of atypia were found at histopathological examination. The development of meningiomas after low-dose irradiation with long latency periods, the predominant calvarial location of the tumors, the high recurrence rates, the absence of malignant traits but the presence of atypias are features overwhelmingly common with similar cases published in the literature. The fact that two of the five patients were sisters stresses the importance of genetic factors in the evolution of these tumors.
PURPOSE: To determine the rate of retinal detachment after treatment of retinoblastoma, to describe the clinical features and management, and to discuss possible pathogenic mechanisms. METHODS: We retrospectively analyzed the charts of 80 patients (83 eyes) with retinoblastoma treated conservatively between 1963 and 1994, looking specifically for cases that developed a retinal detachment after treatment. RESULTS: Five patients (5 eyes, stages IVa to Vb) developed a retinal detachment after treatment. Of these, four had undergone external radiotherapy and one had an episcleral cobalt plaque. Retinal detachment developed within three months after radiotherapy and relentlessly progressed in all four eyes over a period of five months to four years. In the eye that received the episcleral cobalt plaque, the detachment remained localized inferiorly. Even though no retinal break could be detected in four eyes, the clinical features were suggestive of a rhegmatogenous detachment: there was retinal thinning adjacent to the regressed tumors, and the evolution was much longer than that of an exudative retinal detachment. A scleral buckling procedure was performed in two eyes and the retina was successfully reattached. The retinal detachment was not operated on in the three other eyes: the hole was too posterior in one eye; retinal surgery was refused in the second eye; and the retinal detachment remained localized inferiorly in the third eye. CONCLUSION: A retinal detachment developed in 6% of eyes after conservative treatment of retinoblastoma. The possibility of a rhegmatogenous origin should be considered even if no retinal break is detected. In the absence of tumor activity, a scleral buckling repair could be carefully considered if the retinal detachment threatens the macula, and if its evolution is not indicative of an exudative detachment.
Human testicular germ-cell tumors (TGCTs) comprise a heterogeneous group of solid neoplasms. These tumors are characterized by the presence of a highly specific chromosomal abnormality, i.e., an isochromosome of the short arm of chromosome 12. At present, this i(12p) chromosome is found in more than 80% of TGCTs. Isochromosome 12p has also been observed in some ovarian and extragonadal germ cell tumors. In the remaining so-called i(12p)-negative TGCTs other abnormalities involving chromosome 12, mainly 12p, can be found. In order to establish whether 12p abnormalities other than i(12p) are a common phenomenon in TGCTs, a panel of 11 i(12p)-negative tumors was investigated using multicolor fluorescence in situ hybridization. All TGCTs examined appeared to contain chromosomal abnormalities involving 12p, resulting in a distinct overrepresentation of short arm sequences. In addition, indications were obtained for a clonal evolution in one of the tumors. Our data suggest that the occurrence of 12p abnormalities is a common phenomenon in i(12p)-negative TGCTs and that these abnormalities, analogous to i(12p), may contribute to the process of tumor development.
A particular translocation between chromosomes 8 and 14 has been found repeatedly in cytogenetic studies of Burkitt lymphoma, both of African and non-African origin. We report here our findings in cytogenetic studies of direct tumor preparations from 18 non-African Burkitt lymphoma patients, 9 of whom also had cell lines available for study. A t(8;14) was found in direct tumor material in 10 of the 18 patients. Seven of the 9 cell lines had a t(8;14). A total of 15 patients had either a t(8;14) or a 14q+ present in tumor material and/or cell lines. In addition, 8 patients had a peculiar marker chromosome 1. The t(8;14) was not found in every malignant cell and, where present, it was rarely the sole karyotypic abnormality. The relationship of the t(8;14) to the evolution of the tumor is discussed.
OBJECTIVE: Treatment modalities for acoustic neuroma (AN) include surgery, observation and gamma-knife surgery. The aim of this study was to compare neurotological complications resulting from two treatment alternatives to microsurgery: radiosurgery and observation. MATERIAL AND METHODS: We conducted a systematic review of the literature dealing with radiosurgery for AN and compared the rate of neurotological complications in this population with that in a cohort of patients managed conservatively. RESULTS: We found that neurotological complications, namely facial hypoesthesia (p = 0.002), hearing loss (p < 0.05) and hydrocephalus (p = 0.02), were more frequently encountered after radiosurgery than with conservative management. In contrast, we found that the risk of growth of AN is significantly higher with conservative management and that the rate of stability of the tumor did not differ significantly between the two treatments. CONCLUSION: We prefer a conservative management regimen for patients who cannot be operated on for their AN. However, there are some difficulties inherent in this conservative management policy, namely non-compliance and difficulties in establishing the evolution of the tumor.
The results of the treatments of the ovarian tumors are very different according to the numerous statistics. These discrepancies are linked with the difficulties in interpreting the histologic and cytologic criteria. Clinicians and pathologists are sensibilized by the severity of the ovarian cancer and carry out heavy therapies out of proportion with the potential evolution of the tumor. The aim of this work, which was presented at a meeting during the Assises d'anatomic pathologique (Brussels, 26-28 March 1981), is to specify the histologic and cytologic characters permitting to isolate the ovarian border-lesions which have a much better prognosis than the ovarian carcinomas grade I.