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PubMed2003

Fetal brain tumors.

INTRODUCTION: Fetal intracranial tumors are rare and their evolution is usually poor. With routine use of antenatal ultrasound imaging, a larger number of such tumors have been diagnosed. METHODS: During the period from January 1992 to January 2002, 18 cases diagnosed as intracranial tumors in the fetal stage were treated in the Neurosurgery and Obstetrics Departments of the Federal University of São Paulo and in the Fetal Medicine Service of the Maternity Hospital Santa Joana. RESULTS: The tumors most frequently found were those of the choroid plexus and teratomas. Out of those 18 cases, 11 patients presented with fetal hydrocephalus, and 5 of them, who were less than 34 weeks old (gestational age), underwent repeated cephalocenteses while awaiting better conditions for delivery. Two fetuses died while in utero before any intervention had taken place and 16 underwent craniotomy after birth. Twelve of those patients are still alive, 9 of whom are considered normal. The 3 others are slightly or moderately retarded.

Amniocentesis↗

PubMed1983

[Cutaneous apudoma. Apropos of a case and review of the literature].

It has been suggested that Merkel Ranvier cells, generally considered as belonging to the Apud system, may be the origin of extremely rare skin tumors. The authors analyse the characteristics of an apudoma in connexion with a case, and compare their findings with those of 58 other cases reported in the literature. With light microscopy techniques, the differential diagnosis is essentially one of a non-differentiated primary or secondary carcinoma, or of a lymphosarcoma. Detection by electron microscopy of neurosecretory granules in the cell cytoplasm, the neuron-specific enolase activity, when this is detectable, the possibility of ectopic polypeptide secretions, and the evolution potential of the tumor, are all features warranting inclusion of this type of tumor in the category of apudomas.

APUD Cells↗

PubMedDate not supplied

[Cylindroma of the base of the skull with longstanding neurological disturbances. Anatomo-clinical correlation].

The authors present the clinico-pathological correlation in a women who developed at the age of 43 years progressive pain in the left hemiface with motor and sensitive disorders of the left trigeminal nerve. Progressive involvement of the left IIIrd, IVth and Vth cranial nerves appeared with persistence of intractable facial pain which was not responsive to treatment by Tegretol, nor by thermocoagulation of the left Gasserian ganglion. Partial resection of a tumor was performed. The biopsy revealed its cylindromatous nature. The patient died after eight years of evolution. Autopsy confirmed an extensive tumoral invasion of the left temporal bone with invasion of the dura, the left cavernous sinus, and tumoral infiltration of the IIIrd, IVth, Vth and VIIIth cranial nerves on the left side. Metastases of the cylindromatous epithelioma were found in the liver and adrenals. The precise origin of the tumor could not be ascertained.

Adrenal Gland Neoplasms↗

PubMed2004

[Pleomorphic adenoma of nose and accessory nasal sinuses: a report of 15 cases].

OBJECTIVE: To discuss the clinical characteristics and the treatment of pleomorphic adenoma of nose and accessory nasal sinuses (NPA). METHOD: Fifteen cases of NPA were treated, 2 cases underwent radical maxillary sinusotomy, 2 cases nasal polypectomy, 10 cases lateral rhinotomy and 1 case maxillectomy. RESULT: No recurrence occurred in 7 cases, recurrence occurred in 6 cases, planted recurrence occurred in 1 case, malignant evolution occurred in 1 cases (carcinosarcoma) after the first operation. The 6 cases of recurrence underwent an operation for the second time, 2 cases had no recurrence, 2 cases recurred again, 2 cases became malignant (one was adenoid cystic carcinoma, the other was squamous cell carcinoma). The case who was planted recurrence underwent radiotherapy with 60 Gy and died of failure to respond to medical treatment at last. CONCLUSION: The rate of recurrence and misdiagnosis is very high in NPA, this tumor can be malignant evolution easily after many operations. To get rid of focus completely, it is important to apply a wide range of surgical operation in the first operation, which is the key to treatment. Rapid sections-cutting for microscopic examination should be done during operation, biopsy must not be done before operation if a tumour of nose is suspected to be NPA. Prognosis of this tumour is mainly linked to recurrences in cases of incomplete resection and to possible metastasis, such as an eventual malignant evolution.

Adenoma, Pleomorphic↗

PubMed2001

A 23-year experience with malignant renal tumors in infancy and childhood.

A retrospective analysis of 77 children treated between 1974 and 1996 was undertaken to evaluate morbidity and the evolution of therapy. A Wilms' tumor (WT) was present in 73 children. 74% of patients (pats.) with WT survived (54 of 73 pats.). Histological specimens of 67 patients were re-evaluated, including 4 children with non-WT histology. Among patients with Wilms' tumors (WT), nephroblastoma (NB) of intermediate risk predominated (73%; 46 of 63 pats.). Low-risk tumors occurred in 5 of 63 children (8%; mesoblastic nephroma 3, cystic partially diff. NB 1, completely necrotic NB 1). High-risk WT were diagnosed in 12 of 63 patients (19%) (NB with anaplasia 10, clear cell sarcoma 1, malignant rhabdoid tumor 1). Nephrogenic rests were present in 14 cases. We observed 3 children of school age with renal carcinoma and one patient with an intrarenal neuroblastoma. WT histology was the most important factor determining prognosis (p = 0.018). The risk for relapses was 2.6-fold higher in patients with high-risk WT compared to the standard risk group. Stages were re-evaluated according to SIOP 93-01. Comparing relapse-free survival of stages I, II and III, respectively, there was a reduced survival rate for stage III (p=0.019). According to the SIOP/GPOH protocol in 1989, the regimen was switched from primary surgery to preoperative chemotherapy without biopsy in 1989 (11 pats.). Compared to earlier years, survival improved (n.s.). In 3 patients preoperative diagnosis by means of imaging failed. During preoperative chemotherapy a venous occlusive disease of the liver occurred in 2 patients. Preoperative chemotherapy led to an impressive tumor shrinkage in the majority of patients. 2 patients of the preoperative group died (focal anaplastic NB). Long-term morbidity was analysed in 49 patients and included radiation-induced scoliosis (35), chest-wall deformity (3), congestive cardiomyopathy after relapse (1) and arterial hypertension (2). Over the years there was a trend to reduce frequency and dose of irradiation. Prognosis of WT is excellent but unfavorable histology (high risk) predicts a poor prognosis. In our experience, reduction of tumor volume due to preoperative chemotherapy facilitates tumor removal by surgery and may prevent tumor spillage and the deleterious effects of radiation in young children. Surgery without delay is necessary if the diagnosis is unclear or the tumor fails to respond to preoperative chemotherapy.

Antineoplastic Agents↗

PubMed1996

Testicular cancer.

The rising rate of germ cell cancer of the testis over the past decade has been demonstrated to be occurring predominantly in the younger age group (15 to 19 years) in association with earlier onset of puberty and earlier onset of regular sexual activity. Chemicals and viruses, with their atrophogenic effect, remain the main candidates for inducing the final common pathway of tumor development and clonal evolution, ie, gonadotropin-driven mitosis in spermatogonia. The possibility of different genetic mechanisms regulating susceptibility and resistance to these two extreme causes of gonadal atrophy in families is raised by the failure of a genome screen in a series of sibling pairs with testicular cancer to identify a single significant linkage group. Studies demonstrating high levels of non-mutated p53 protein and rapid induction of apoptosis by chemotherapy provide a new insight into the cause of the exquisite chemosensitivity of these tumors. Durable responses to paclitaxel and in vitro activity in response to temezolamide provide further evidence of the plethora of agents that work against these tumors, although no new first-line therapeutic approaches have been reported recently. The most important clinical trial studied good-risk patients and demonstrated that to gain the benefit of reducing treatment time from 12 to 9 weeks it is essential to retain bleomycin in the BEP (bleomycin, etoposide, and cisplatin) regimen. The final new idea to emerge recently comes from a series of papers on management of primary tumors in patients with a solitary testis and the possible use of organ-conserving surgery plus postoperative radiation. Another study did suggest it might be possible to use preoperative chemotherapy in those wishing to retain spermatogenesis.

Adolescent↗

PubMed1995

Growth of nonnecrotic tumors in the presence and absence of inhibitors.

In this article a model for the evolution of a spherically symmetric, nonnecrotic tumor is presented. The effects of nutrients and inhibitors on the existence and stability of time-independent solutions are studied. With a single nutrient and no inhibitors present, the trivial solution, which corresponds to a state in which no tumor is present, persists for all parameter values, whereas the nontrivial solution, which corresponds to a tumor of finite size, exists for only a prescribed range of parameters, which corresponds to a balance between cell proliferation and cell death. Stability analysis, based on a two-timing method, suggests that, where it exists, the nontrivial solution is stable and the trivial solution unstable. Otherwise, the trivial solution is stable. Modification to these characteristic states brought about by the presence of different types of inhibitors are also investigated and shown to have significant effect. Implications of the model for the treatment of cancer are also discussed.

Cell Division↗

PubMed1999

[A case of metastatic nephroblastoma in an adult with favorable outcome under cisplatyl, etoposide].

Wilm's tumor is exceptional in adulthood. Its treatment is based on radical nephrectomy, adjuvant chemotherapy and radiotherapy. The prognosis is poorer compared with children because adults present more frequently with advanced stages and chemotherapy has a moderate efficacy. The various protocols of chemotherapy and the indications of radiotherapy are not defined with precision, mainly due to the rarity of the disease. The authors report a case of adult Wilm's tumor with a favorable evolution followed 4 years in spite of an unfavorable histology, lung metastases and a relapse after a first chemotherapy.

Adult↗

PubMed2003

Acute respiratory distress syndrome after chemotherapy for lung metastases from non-seminomatous germ-cell tumors.

GOALS: To describe an acute respiratory distress syndrome (ARDS) occurring after chemotherapy for non-seminomatous germ-cell tumors (NSGCT) with diffuse lung metastases, we conducted a retrospective study in a 15-bed intensive care unit (ICU) in a comprehensive cancer center. PATIENTS AND METHODS: During a 10-year period, 16 consecutive patients with diffuse lung metastases from a NSGCT were admitted to the ICU for respiratory distress and high-risk chemotherapy. MAIN RESULTS: Nine patients developed acute respiratory failure requiring mechanical ventilation (MV) within 3 days of the initiation of chemotherapy, while the respiratory status of the seven other patients improved. The evolution was independent of tumor marker levels and the type of chemotherapy regimen. The SAPS II score did not accurately describe the severity of this population. The only predictor of intubation was the initial PaO2/FiO2 ratio upon admission to the ICU. Six out of seven patients who did not require MV were discharged alive from the hospital, whereas all but one patient requiring MV died. Refractory hypoxemia and ventilator-associated pneumonia were the leading causes of death. CONCLUSIONS: Acute respiratory distress in patients with lung metastases from NSGCT is a rare cause of ARDS. Chemotherapy could be responsible for triggering the respiratory worsening. Patients with severe respiratory insufficiency (PaO2 <70 mmHg on room air) on admission to hospital should be promptly transferred to the ICU for the first chemotherapy course.

Adult↗

PubMed1997

Telomeric fusion and chromosome instability in multiple tissues of a patient with mosaic Ullrich-Turner syndrome.

We describe the cytogenetic evolution of multiple cell lines in the gonadal tissue of a 10-year-old girl with mosaic Ullrich-Turner syndrome (UTS) involving clonal telomeric associations (tas) of the Y chromosome. G-band analysis of all tissues showed at least 2 cell lines; 45, X and 46,X,tas(Y;21)(q12;p13). However, analysis of left gonadal tissue of this patient showed the evolution of 2 additional cell lines, one designated 45,X,tas(Y;21)(q12;p13),-22 and the other 46,X,tas(Y;21)(q12;p13),+tas(Y;14)(q12;p13), -22. Fluorescence in situ hybridization (FISH) analysis of interphase nuclei from uncultured gonadal tissue confirmed the findings of aneuploidy in the left gonadal tissue and extended the findings of aneuploidy to the tissue of the right gonad. The chromosome findings in the gonadal tissue of this patient suggest a preneoplastic karyotype relating to several distinct tumor associations. The clonal evolution of telomeric fusions indicates chromosomes instability and suggests the extra copy of the Y chromosome may have resulted from a fusion-related malsegregation. In addition, the extra Y suggests low-level amplification of a putative gonadoblastoma gene, while the loss of chromosome 22 suggests the loss of heterozygosity for genes on chromosome 22. This case demonstrates the utility of the study of gonadal tissue in 45,X/46XY UTS patients, and provides evidence that clonal telomeric fusions may, in rare cases, be associated with chromosome malsegregation and with the subsequent evolution of unstable karyotypes.

Child↗

PubMed2005

Resection of parietal lobe gliomas: incidence and evolution of neurological deficits in 28 consecutive patients correlated to the location and morphological characteristics of the tumor.

OBJECT: The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. METHODS: Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance (MR) images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyrus. The tumors were located in the dominant hemisphere in 18 patients (64%); had a mean diameter of 39 mm (range 14-69 mm); were isolated to the superior parietal lobule in six patients (21%) and to the inferior parietal lobule in eight patients (29%); and involved both lobules in 14 patients (50%). Gross-total resection, documented by MR imaging, was achieved in 24 patients (86%). Postoperatively, nine patients (32%) experienced new neurological deficits, whereas seven (25%) had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level (association) parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. CONCLUSIONS: Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits (for example, a visual field loss or cortical sensory syndrome) occurred in patients regardless of hemispheric dominance.

Adult↗

PubMed1989

Chromosomal evolution in the progression and metastasis of human malignant melanoma. A multiple lesion study.

In order to distinguish those chromosomal aberrations associated with tumorigenesis from those associated with tumor progression of malignant melanoma, chromosome analysis was performed on eight tumors derived from one patient. Three common marker chromosomes, a deletion of chromosome 1, a deletion of chromosome 9, and a translocation involving chromosomes 7 and 12, were identified in each tumor. The presence of common markers in these intrapatient tumors indicates the monoclonal origin of these tumors. Furthermore, the consistent and specific involvement of chromosome 9 in both interpatient and intrapatient studies suggests the crucial role that chromosome 9 plays during the development of human malignant melanoma. In addition to common markers, different overlapping markers including those involving chromosomes 2, 3, and 6, were also identified, suggesting that chromosomes 2, 3, and 6 are most likely associated with the progression, instead of the genesis, of the tumor. Finally, lesion-specific marker chromosomes were identified in each tumor indicating the nonrandom selection and modification of the metastatic process. The nature of chromosomal evolution among the eight tumors was clearly demonstrated by the retention and amplification of specific marker chromosomes, with the latter tumors containing more overlapping markers than the early tumors and the recurrence of identical markers in the different branches of evolution. One of the last three tumors obtained immediately before the death of the patient contained all the overlapping markers identified in other tumors, which may indicate that a plateau of chromosomal evolution of these tumors has been reached. These observations demonstrate a nonrandom or programmed chromosome evolution of human neoplasia that could be intrinsic to the aneuploid nature of neoplasia.

Chromosome Aberrations↗

PubMed2001

[Port-site metastasis after laparoscopic resction of a duodenal stromal tumor].

Gastro-intestinal stromal tumors are rare and their evolution is dubious. This observation of port site metastasis after laparoscopic resection of a small duodenal stromal tumor would be, to our knowledge, the first case reported in the literature. Several direct and indirect mechanisms were supposed to be involved in the appearance of metastases after laparoscopic surgery, but the risk of dissemination remains badly evaluated on its frequency as well as on its mechanisms.

Aged↗

PubMed2002

Multivariate analysis of chromosomal imbalances in breast cancer delineates cytogenetic pathways and reveals complex relationships among imbalances.

More than 550 breast adenocarcinomas with clonal chromosomal abnormalities have been reported. Although the aberration pattern is clearly nonrandom, no specific primary or secondary karyotypic abnormality has been identified, and furthermore the chronological order in which the aberrations appear during disease progression is not well known. The high degree of karyotypic complexity in epithelial tumors such as breast cancer is one reason why our understanding of the sequential order of cytogenetic evolution is unclear. To overcome some of these difficulties, we have used several statistical methods that allow identification and interpretation of karyotypic pathways. These methods were applied on 538 breast cancer karyotypes. The distribution of the number of imbalances/tumor showed a monomodal appearance, indicating that one single mode of karyotypic evolution is operating in this tumor type. We show that there exists a temporal order with respect to the appearance of chromosomal imbalances. The imbalances +1pq, 1q-, 3p-, and +7 appear earlier than expected from random events, and two cytogenetic pathways, one initiated by +1q and followed by 11q- and -22, the other initiated by either 3p- or 1q- and followed by 1p-, 3q-, and 6q-, can be discerned. We also show that +7 and +8q behave independently of the other imbalances and cannot, by simple means, be incorporated in the identified pathway scheme. Although the cytogenetic pathways are well separated at earlier stages, they later converge and include a common set of late imbalances.

Adenocarcinoma↗

PubMed2004

Evolution of the HIV-1 envelope glycoproteins with a disulfide bond between gp120 and gp41.

BACKGROUND: We previously described the construction of an HIV-1 envelope glycoprotein complex (Env) that is stabilized by an engineered intermolecular disulfide bond (SOS) between gp120 and gp41. The modified Env protein antigenically mimics the functional wild-type Env complex. Here, we explore the effects of the covalent gp120 - gp41 interaction on virus replication and evolution. RESULTS: An HIV-1 molecular clone containing the SOS Env gene was only minimally replication competent, suggesting that the engineered disulfide bond substantially impaired Env function. However, virus evolution occurred in cell culture infections, and it eventually always led to elimination of the intermolecular disulfide bond. In the course of these evolution studies, we identified additional and unusual second-site reversions within gp41. CONCLUSIONS: These evolution paths highlight residues that play an important role in the interaction between gp120 and gp41. Furthermore, our results suggest that a covalent gp120 - gp41 interaction is incompatible with HIV-1 Env function, probably because this impedes conformational changes that are necessary for fusion to occur, which may involve the complete dissociation of gp120 from gp41.

Amino Acid Substitution↗

PubMed2002

[The Marjolin's ulcer, destiny of a unstable scar. About 54 cases of burn's sequelae].

Through a study of 54 cases of malignant transformation on burn's scar, collected during a period of 8 years, the authors underline the particularities of this tumor, reported at the literature such as the preponderance of spinocellular carcinoma as histological type, the high rate of lymphatic metastasis and recurrence, and also the poor prognosis. In addition, the authors underline the non-rare character of this affection, whose incidence is correlated to the level of medication; it's occurring in younger patients, and its short delay of transformation. The treatment is based on prevention by a correct management of the initial burns, the cure of any instable scar, and a regular surveillance. The biopsy should be realised in case of suspicion of degeneration. The radical treatment must be initially aggressive, consisting on large excision associated eventually to radiotherapy. This treatment must be integrated in an elaborating therapeutic strategy, taking on consideration the evolutive potentiality of these tumors in order to improve chances of recovery and survival.

Adolescent↗

PubMed1989

Sequential bcl-2 and c-myc oncogene rearrangements associated with the clinical transformation of non-Hodgkin's lymphoma.

We report a case of untreated non-Hodgkin's lymphoma with histologic progression over 1 yr from a low-grade, small cleaved follicular center cell lymphoma to a high-grade, small noncleaved follicular center cell lymphoma. Both lymphomas had identical immunoglobulin (Ig) heavy-chain joining gene (JH), kappa light-chain joining gene, and bcl-2 gene rearrangements, indicating the clonal identity of the two tumors. The Ig heavy chain locus on one chromosome 14 was involved in an initial t(14; 18) translocation as shown by comigrating JH and bcl-2 rearrangements. However, the oncogene c-myc was in the germline configuration in the initial lymphoma but had one allele rearranged near the 3' end of exon I in the high-grade tumor; DNA sequence analysis was consistent with a chromosomal breakpoint at that site. The presence of the c-myc rearrangement in the high-grade tumor suggest a role for c-myc in the clonal evolution of the low-grade tumor into a more aggressive lymphoma. The coexistence of both bcl-2 gene and c-myc oncogene rearrangements in the same tumor is unusual, with only a few cases reported. Furthermore, this case is unique in the direct demonstration of the histologic and clinical progression of a human lymphoma associated with the sequential rearrangement of the bcl-2 gene and the c-myc oncogene.

Base Sequence↗

PubMed1991

[Brain tumors in nursing infants].

The purpose of this study was to determine the anatomical-pathological distribution of brain tumors in children under two years of age and their clinical characteristics (age, sex, time span from the start of symptoms or signs to the time the tumor was diagnosed, main clinical manifestations, evolution and prognosis). From 1981 to 1989, 16 children with brain tumors, under two years of age, were studied. The tumors arose in 13 patients during first year of life and during the second, in the remaining three. In 50% of the patients, the tumors were supratentorial. The histological diagnosis was made in all cases, finding the ependymoma the most frequent tumor, followed by the astrocytoma and other tumors: teratoma, choroid plexi papilloma. The increase in size was within the cephalic perimeter, with a risen fontanelle, irritability, vomiting and convulsive episodes, as main clinical manifestations. In 15 of the patients a partial or total resection of the tumor was performed, 6 were given radiotherapy and 2 chemotherapy. The prognosis correlated with the greatest surgical risk, the anatomical-pathological characteristics and the lateness in its diagnosis. We emphasize the greater morbi-mortality rate with respect to other pediatric ages.

Age Factors↗