Search

Background: Cytogenetic studies of meningiomas suggest that loss of (or parts of) chromosome 22 is a primary event in the development of these tumors; later on, other chromosomal changes would occur in the caryotypes. All these secondary changes are observed mainly in cases with high clinical aggressivity. However, in a few cases of meningiomas disomy 22 coexists, but with other chromosomic anomalies. We present clinical, histopathological and cytogenetic findings in a group of meningiomas with disomy of chromosome 22., Patients and Methods: We collected 10 meningiomas from nine patients which ages ranged between 28-70 years. Fresh tumoral specimens were divided for histologic examination and cytogenetic study, performed after short-term culture., Results: At microscopic examination 5 tumors were classified as benign meningiomas, four as atypical and one as malignant meningioma. Four cases were recurrent tumors. The cytogenetic studies showed that all tumors presented two chromosomes 22 and other chromosome abnormalities. Losses in chromosomes 4, 7, 10, 14, 16, 17 and 20 were frequent; cytogenetics rearrangements of chromosomes 1, 4, 5, 7, 14, 19 and 22 were frequently involved., Conclusions: In karyotypic evolution of meningiomas, secondary anomalies of chromosomes 1p, 10 and 14 are the most common and appear to be associated with a more aggressive clinical course. In this group of meningiomas with disomy 22, these anomalies were also frequently found, and were related in 50% of cases with atypical or malignant morphologies and of them with recurrent tumors in the 40%.

The original tumor and 4 relapses of a recurrent meningioma were studied. We analyzed and compared these recurrences by histopathology, PCNA labelling index (PCNA-LI), nuclear count, and cytogenetical findings. The most important changes in the evolution to aggressivity were: recurrences at progressively shorter intervals, increases in the PCNA-LI, and micronecrosis; histological changes such as sheeting and increase of the extracellular matrix and a gradual transformation to a clonally complex karyotype.

Cytogenetic analyses of four malignant mixed mesodermal tumors (MMMT) of the uterus are reported, of which one was of the homologous type and three of the heterologous. Karyotypic analyses were obtained in two cases from original tumors and in two cases from tumors xenotransplanted into nude mice. The karyotype of the homologous MMMT was normal in three different passages of a nude mice xenograft line established from the primary tumor. The heterologous tumors showed normal karyotype in one case and hyperdiploid and near triploid range with extensive numerical and structural rearrangements in two cases. Deletion of chromosome 1 at p32, and deletion of chromosome 11 at q13 were common markers in anomalous cases. The chromosomes most often involved in structural rearrangements were chromosomes 1, 9, 11, 12, 17, and 19. Double minutes, homogeneously staining regions, and telomeric association were also seen.

Medulloblastoma is the most common primitive neuroectodermal tumor (PNET) in children, but is very rare in adults. An isochromosome for the long arms of 17, i(17q), is found in about 30% of pediatric cases. Cytogenetic studies in adults are very scarce; only six cases have been described cytogenetically: three cases had normal karyotype, two were studied partially, and another presented only two clonal structural anomalies: del(9)(q12) and del(11)(q22). We studied the chromosomes from medulloblastoma in a 27-year-old woman and found one hypotetraploid stemline with clonal alterations. In the structural anomalies, chromosomes 3, 9, 12, and i(17q) were involved. Chromosome 9 presented a deletion in the long arm, del(9)(q13), with consequent loss of the 9q13-->qter region. This anomaly was similar to one found in a previous case. We suggest that the partial loss of the long arm of chromosome 9 may be a characteristic change of adult medulloblastoma.

Cytogenetic analysis of 8 cases of xenografted human osteosarcomas are reported, including six newly diagnosed and two recurrent tumors. Histologically five were osteoblastic, two were chondroblastic, and one was the microcellular type. All tumors were studied in short-term primary cultures between two and six days. Clonal and nonclonal abnormalities were present in the eight cases; four had a chromosome number in the hypotriploid range, two in the hyperdiploid, one in the hypodiploid, and one in the hypertetraploid range. All cases had complex karyotypes and the recognizable structural rearrangements clustered to chromosome arms 1p, 1q, 3p, 5p, 6q, 11p, 13p, 14p, 15q, 16p, 16q, 20q, 21p, and 22q. Seven cases presented double monosomy 17 and six tumors showed double minutes (dmin) or a homogeneously staining region (hsr). This fact has been described recently and its relation with the amplification of the MDM2 gene observed in osteosarcomas is as yet unknown.

Cytogenetic analyses of 10 cases of recurrent meningiomas growing in culture between 1-10 days are reported, of which seven showed benign morphology, one atypical, and two, malignant features. Normal karyotypes with nonclonal alterations were found in three cases, one case with only monosomy 22, and complex karyotypes in the remaining six. Four cases were hypodiploid, one pseudodiploid, and one hyperdiploid. The chromosomes most often involved in structural rearrangements were 1, 7, and 14 and the losses were chromosomes 7, 10, 14, 15, 18, and 22. Ring chromosome, dicentrics, double minutes, and association between satellites were found in one case. These complex karyotypes with hypodiploidy, structural rearrangements, and other markers in recurrent meningiomas may indicate aggressive tumor characteristics.

We studied a case of adenoid cystic carcinoma. Cytogenetic analysis was performed on short-term culture, and the karyotype revealed only an abnormal cell line with the following changes: partial trisomy 5q, 6q deletion, monosomy of chromosome 9,der(10)t(10;15), a possible ring chromosome 22, and loss of the Y chromosome. The implication of chromosomes 6 and 9 is considered in relation to the karyotypic evolution of this type of tumor.

Angiosarcoma of the breast is quite rare, and the development of cutaneous angiosarcoma after segmental mastectomy and radiation therapy is even less common. A cytogenetic analysis of a mammary angiosarcoma arising in a breast after previous irradiation and segmental mastectomy for infiltrating ductal carcinoma revealed multiple clonal rearrangements involving chromosomes X, 1, 2, 3, 4, 5, 6, 7, 8, 9, 15, 17, 20, and 22. No cytogenetically analyzed angiosarcomas of the breast have been reported before.

We studied a case of typical syncytial meningioma. Cytogenetic analysis of the tumor cells showed a karyotype with normal chromosomes 22 and only one anomaly, del(1)(p32). Cases of meningiomas with normal chromosomes 22 and other anomalies are rare, and it is difficult to correlate their histologic characteristics and biologic behavior.

A 17-year-old girl was referred to us because of primary amenorrhea and features of Turner's Syndrome. The karyotype obtained from peripheral lymphocytes cultures was mos 45,X/46, XYnf/47, XYnfYnf/46, X, dic (Ynf) (q12). The karyotype of fibroblasts derived from cultures of both gonads was mos 45, X/46, XYnf/47, XYnfYnf. The Y chromosome was non-fluorescent in all the examined lines. We report here the clinical and cytogenetic findings in a patient with an unusual sex chromosome mosaicism.

Cytogenetic, flow cytometric, cytophotometric and morphometric analyses were performed on 22 previously untreated, primary solid breast carcinomas. Although the cell nuclei as the primary object of these studies were the same in all the tumors, distinct features were evaluated in each case to determine to what degree the results obtained by these techniques are comparable. From the cytogenetic viewpoint, six tumors had a modal number in the diploid range, seven were in the triploid range, and two in the tetraploid range; seven tumors had no modal number. These data correlate with the flow cytometry and cytophotometry results obtained, with DNA values slightly higher than their respective chromosomal modes. However, no correspondence between chromosomal modes and mean nuclear area was found. Chromosomal markers have been identified that particularly affect chromosomes 1 (p11, q21-qter), 11 and 16, although no common markers existed in all cases. Cytogenetics is the most sensitive technique, but the low yield (22 out of 140 tumors assayed) considerably restricts its value in any prospective breast cancer study.

We present two new cases of Y-autosome translocation which were detected in two azoospermic males. In the first case the translocation was de novo with the karyotype: 46,XY,t(Y;16)(q12;q11-12). In the second case the karyotype was: 46,XY,t(Y;1)(cen-q11;cen-p11), t(Y;15)(q12;p11), the mother having been a carrier of the same Y-15 translocation, and showing the chromosomic formula: 46,XX,t(Y;15)(q12;p11).

Cytogenetic studies were performed in nine patients with non-Hodgkin's lymphoma; four were lymphoblastic lymphoma, three Burkitt's-type and two diffuse lymphomas with mixed small and large cell. All cases showed pseudodiploid or hyperdiploid mode and, moreover, four cases had metaphases with a normal karyotype. All patients showed clonal chromosomal abnormalities, except one (lymphoblastic T-lymphoma). The translocations t (8;14) (q24;q32) and t (8;22) (q24;q11) were the abnormalities found in Burkitt's lymphoma. The translocation t (14;18) (q32;q21) was found in one case, of lymphoblastic type. In the other tumours, the chromosomes involved in the different aberrations were: #1, #3, #7, #8, #9, #14 and #17. We attempted to correlate the cytogenetic findings with histology and prognosis.

We report a case of an immature malignant ovarian teratoma with peritoneal implants diagnosed in an 18-year-old woman. The tumor was brought into remission after surgery (three laparotomies) and adjuvant chemotherapy. A residual peritoneal implant showed a mature epithelial and glial configuration. Histologically, the neuroectodermal component was dominant in the original tumor as well as in the metastases, being confirmed by immunohistochemistry and electron microscopy. A stem cell line has been obtained with cell culture, having a germ cell character and a yolk sac configuration. This line possessed a trisomy 12 and a translocation (7;9) similar to other chromosomal abnormalities described in immature teratomas of the testes and ovaries.

A case of familial translocation t(3;22) (q21;q13) detected through a boy carrier with various functional and phenotypical alterations is described. The caryotype study (G bands) showed that the mother, one maternal aunt, two maternal uncles, and the brother of the proband were likewise carriers of the same translocation. We discuss the type of segregation and the high familial incidence of the translocation.

We discuss the morphological, immunohistochemical and electron-microscopical features of a malignant myxoid liposarcoma which appeared in the left thigh of a 52-year-old woman. The cytogenetic analysis following short-term tissue culture confirmed the existence of a nonrandom translocation t(12;16)(q13;p11). Furthermore, immunohistochemistry showed positivity for S-100 antigen and vimentin, both of which are considered to be markers for liposarcoma. The electron-microscopical study revealed a close contiguity between the tumoral cells and atypical pericytes.

A direct cytogenetic analysis was performed on tumor samples obtained from two patients with clinical and histopathologic diagnosis of primary peripheral neuroepithelioma. Both tumors presented the translocation t(11;22)(q24;q12). These results confirm those previously obtained by other authors and suggest a common histogenetic origin for this tumor with Ewing's sarcoma and Askin's tumor, in which the same translocation has been described.

Cytogenetic studies on newborn infants show a high incidence in chromosomal abnormalities (0.5-1% of the population). Chromosomal study is carried out on 750 children from the University Hospital of Valencia over a two-year period, chosen at random and without any clinical pathology. Five gonosomopathies and three autosomopathies were found. In the former, three 47,XXY, one triple-X, and one isochromosome of long arms of chromosome X, were detected. In autosomal chromosomopathies, a Robertsonian translocation was seen between chromosomes 13 and 14, a reciprocal translocation between chromosomes 8 and 10, and an inversion of chromosome 3. Altogether eight cytogenetic anomalies appeared, a percentage slightly over one percent. Importance of early diagnosis of chromosomal abnormalities is discussed, with the aim of establishing adequate treatment when possible, and genetic counselling for the family.