Two lesions, actinic keratosis (AK) and squamous cell carcinoma in situ (CIS), are believed to be precursors of squamous cell carcinoma (SCC) of the skin. These lesions can serve as an excellent model system for studying genetic changes associated with the inception of skin SCC. In the present study, five such lesions of the skin, three AKs and two AK+CIS, from three patients were short-term cultured and analyzed cytogenetically. One of the patients (case 3) had also an SCC in addition to three premalignant lesions. All lesions, but one, showed clonal karyotypic abnormalities. The recurrent changes identified were numerical, that is, +7 and +20. The structural rearrangements found in three AK were different, but it could be noted that the distal part of the long arm of chromosome 4 was involved in two AK and the SCC of case 3A. It was also interesting that chromosome 1 participated in structural rearrangements in three AK with band 1p31 being involved in two tumors. The karyotypic profile of these lesions is compared with that of skin SCC; it turns out that the general patterns are different in the sense that the SCC more often have complex karyotypes and display unbalanced aberrations involving the centromeric regions. Some karyotypic similarities between the SCC and their precursors are revealed. The fact that the structural rearrangements involving chromosomal band 3p13 and the centromeric region of chromosome 3 in AK are common features for many types of malignant tumors, including skin SCC, indicates that these changes are early genetic events associated with malignant transformation.

Cytogenetic analysis of short-term cultured 44 basal cell carcinomas (BCC) revealed clonal karyotypic abnormalities in 38 tumors. Relatively complex karyotypes (at least four structural and/or numerical changes per clone) with unbalanced structural as well as numerical aberrations were found in eight (approximately 21%) of the BCC, while the remaining BCC (79%) had simple karyotypes (1 to 3 aberrations per clone). Numerical changes only were found in 16 tumors, 15 BCC displayed both numerical and structural aberrations, and the remaining 7 BCC showed only structural aberrations. Extensive intratumoral heterogeneity, in the form of cytogenetically unrelated clones, was found in 21 tumors, whereas related subclones were present in 10 tumors. In order to obtain an overall karyotypic picture in BCC, the findings of our previously published 25 BCC have been reviewed. Our combined data indicate that BCC are characterized by nonrandom karyotypic patterns. A large subset of BCC is characterized by nonrandom numerical changes, notably, +18, +X, +7, and +9. Structural rearrangements often affect chromosomes 1, 4, 2, 3, 9, 7, 16, and 17. A number of chromosomal bands are frequently involved, including 9q22, 1p32, 1p22, 1q11, 1q21, 2q11, 4q21, 4q31, 1p36, 2q37, 3q13, 7q11, 11p15, 16p13, 16q24, 17q21, and 20q13. When the genomic imbalance is assessed, it has been shown that several chromosome segments are repeatedly involved in losses, namely loss of the distal part of 6q, 13q, 4q, 1q, 8q, and 9p. A correlation analysis between the karyotypic patterns and the clinico-histopathologic parameters has been undertaken in the 44 BCC of the present series. The cytogenetic patterns show a significant correlation with tumor status (P=.025), that is, that cytogenetically more complex tumors are also those clinically the most aggressive. Also, the frequency of cytogenetically unrelated clones is significantly higher in recurrent BCC than that in primary lesions (P=.05). No clear-cut association has been found between the karyotypic patterns and histologic subtypes or tumor sites.

We report the finding of clonal chromosome abnormalities in 13 short-term cultured squamous cell carcinomas (SCCs) of the skin. Intratumor heterogeneity, in the form of cytogenetically related (subclones) or unrelated clones, was detected in six tumors. Whereas clones with complex karyotypic changes were found in 6 tumors, clones with simple anomalies were observed in 10 tumors, and sometimes these clones coexisted with highly abnormal clones. Rearrangement of chromosome 8, in the form of isochromosome i(8q) or whole arm translocation, was the most common aberration, found predominantly in complex clones. Another recurrent feature, i.e., the centromeric rearrangement of chromosome I, as isochromosome i(1q) or i(1p), or whole arm translocations, was always part of a complex karyotype. Homogeneously staining regions were found in two cases, one with a highly complex karyotype and the other with a simple karyotype. In order to obtain an overall karyotypic picture in SCC of the skin, the cytogenetic findings in 10 SCCs reported earlier were reviewed. The chromosomes most commonly affected were, in decreasing order, chromosomes I, 11, 8, 9, 5, 3, and 7. Chromosomal sires most frequently rearranged were almost all pericentromeric: they were 8q10-q11, 1p10-q12, 5p10-q11, 11p15, and 9p10-q10. Recurrent anomalies were i(1q), i(8q), i(5p), i(1p), i(9p), and i(9q). Among them, only i(8q) and i(9q) might be assumed to be early genetic events, considering the fact that they could occasionally be identified in simple clones. The most frequent losses included part of or the entire chromosomes 2, 4, 9, 11, 14, 18, and 21, arm 8p, and chromosomes X, Y, and 13. Overrepresentation most frequently involved I q, chromosome 7, and 89. The characteristic karyotypic pattern observed in skin SCC was in line with the experience in several other carcinomas. (C) 1999 Wiley-Liss, Inc.

We have cytogenetically and by fluorescence in situ hybridization (FISH) analyzed short-term cultures from a malignant eccrine poroma, a type of tumor in which chromosomal abnormalities have previously not been reported. Combining the results from G-banding and FISH, the karyotype was interpreted as 50,XX,t(3;11;12)(q21;p15;q15),+5,+7,+9, +9,t(12;22)(q13;q13),+del(12)(q15),der(15)t(3;15) (q23;p13),der(17)t(8;17)(q22;p13),-20,add(22)(q13).

Clonal chromosome abnormalities were found in 22 of 23 short-term cultured basal cell carcinomas (BCC) of the skin. The karyotypic abnormalities were nonrandom and in several cases included evidence of clonal evolution. Especially in cultures showing an epithelial growth pattern, simple numerical changes, most commonly +18, +9, +20, +7, and +5, predominated and presumably constitute pathogenetically important aberrations present in the neoplastic parenchyma, Also, several structural rearrangements of chromosome arm 9q were seen, which may be of particular interest against the background that a gene for familial BCC (Gorlin syndrome), the PTCH gene, maps to this region. Finally, most of the clonal aberrations detected in predominantly fibroblast-like cultures are likely to reflect changes acquired by cells of the tumor stroma, which raises the question whether mutations also of this tumor component may play a pathogenetic role in BCC development.

The reciprocal translocation t(9;16)(q22;p13) was identified in three short-term cultured basal cell carcinomas (BCCs). The t(9;16) was the sole anomaly in one clone in two tumors and was accompanied by a second change that also affected the long arm of chromosome 9 in the third. In addition, other cytogenetically unrelated abnormal clones were also found in all three BCCs. The identification of t(9;16)(q22;p13) as a primary chromosomal abnormality in a subset of BCCs (we found it in 3 of 22 tumors) is especially intriguing against the background that the PTCH gene, which when mutated in the germ line presumably gives rise to the autosomal dominant basal cell nevus or Gorlin's syndrome, maps to chromosome band 9q22. None of the genes rearranged in the BCC-specific t(9;16)(q22;p13) translocation have been identified, but we hypothesize that the translocation represents the cytogenetic corollary of a tumorigenic recombination of PTCH with an as yet unknown gene in 16p13. If so, this would be the first time that a tumor suppressor gene causally involved in a hereditary cancer is shown to be frequently rearranged through a specific translocation in sporadic carcinomas of the same type.

Short-term cultures from a clear cell hidradenoma, a benign skin tumor for which no chromosome data exist, were cytogenetically analyzed. A total of eight unrelated aberrant clones were identified. The karyotypic profiles of two separately processed parts of the sample--a tumor nodule and seemingly normal adjacent dermal tissue--were different. Characteristic for the tumor nodule was a single abnormal clonal population consisting of three subclones: 46,XY,der(2)inv(2)(p13q23)t(2;9)(p13;q22), der(9)t(2;9)(q23;q22),t(11;19)(q21;p13),t(12;19)(q24;p13)/46,idem, inv(1)(p32q44)/92,idemx2. The adjacent tissue contained, in addition to the clone found in the tumor nodule, a spectrum of unrelated clones, the largest of which also showed clonal evolution: 45-47,XY,t(3;6)(p25;p25),t(12;17)(q15;q12),-17,+r(17)x2 [cp]/45-47,idem,inv(5)(p15q22)/90-94,idemx2. The remaining six clones found in this part were small and had simpler numerical or structural aberrations. The multiclonal pattern observed in this hidradenoma seems to reflect both cytogenetic convergence and divergence during neoplastic progression. The presence of unrelated clones may be an indication that the tumor was of multicellular origin.

Cytogenetic analyses of tumors of the skin and upper aerodigestive tract have repeatedly revealed small, pseudodiploid clones characterized by balanced structural rearrangements and a high frequency of cells with nonclonal structural aberrations. However, the lack of common cytogenetic denominators within the different histologic subtypes, the discrepancy between cytogenetic findings and data obtained from flow cytometric DNA content studies, and the occasional identification of tumors with massively rearranged karyotypes indicate that the chromosome rearrangements present in pseudodiploid cells have little to do with the tumorigenesis or progression. Further support for this conclusion, and indirect evidence that the pseudodiploid clones probably do not represent the tumor cell populations, derives from the present study in which clonal and nonclonal structural rearrangements were also found in short‐term cultures from nonneoplastic skin and pharyngeal mucosa. It is possible that the aberrations are present in subepithelial fibroblasts that have accumulated DNA damage due to extensive exposure to potentially carcinogenic agents.

Cytogenetic analysis of short-term cultures from 33 basal cell carci nomas (BCC), a type of neoplasm for which no previous karyological data exist, revealed clonal chromosome aberrations, all of them different, in 8 tumors. In 2 cases, 2 cytogenetically unrelated clones were detected, suggesting a multicellular origin in at least a subset of BCC. A remarkably high level of nonclonal structural rearrangements, mostly in the form of seemingly balanced translocations, was found in 23 tumors; namely, in 6 of 8 BCC with clonal karyotypic abnormalities and in 17 of 25 without. It is possible that some of these aberrations represent additional neoplastic clones, thus indicating an even higher level of Cytogenetic heter ogeneity in BCC. We think that the most likely interpretation of the results is that BCC may have a multicellular origin, reflecting field cancerization of the skin. During subsequent tumor development, the selection pressure narrows down the number of clones that infiltrate the surrounding tissue. The finding by karyotypic analysis of some apparently monoclonal, some polyclonal BCC, may reflect that different tumors have been examined at different points in the clonal evolution of the neoplastic cells.

Cytogenetic analysis of short-term cultures from a basosquamous papilloma revealed the following mosaic karyotype: 46,XX,t(2;5)(q31;q31),t(8;15)(p21;q21)/46,XX,t(7;17)(p13;p13)/47,XX, t(3;20)(q12;p13),+7/46,XX,t(1:12)(p12;q13). The finding of four abnormal, cytogenetically unrelated clones suggests a multicellular origin of this benign skin tumor. None of the structural rearrangements encountered have previously been associated with neoplasia.

Clonal chromosome abnormalities were found in short-term cultures from two epithelial skin tumors, a basal cell papilloma and a keratoacanthoma. The three-way translocation t(2;6;11)(q21;q27;p13) was the sole clonal rearrangement in the basal cell papilloma. The karyotype of the keratoacanthoma was more complex: 46,XX,der(2)(2pter→2p13::2p11→cen→ 2q37::5q33→5qter),der(2)(:2p13→cen→2q37::6q23→6qter),der(5)t(2;7;5)(q37;q11;q33),der(6) (6pter→cen→6q23::2p13→2pter),der(7)t(2;7;5)(q37;q11;q33),del(13)(q11q14). In addition, several nonclonal structural changes were seen in both tumors.

Short-term cultures from three invasive squamous cell carcinomas of the skin were cytogenetically analyzed. Clonal chromosome aberrations were found in all tumors. In the first case, two of three abnormal clones were related, and in the second case, two of five clones demonstrated cytogenetic similarities. Both clones detected in case 3 had a structural rearrangement in common. Several nonclonal changes were seen in all three cases in addition to the clonal aberrations. None of the rearrangements detected, clonal or nonclonal, corresponds to any of the consistently cancer-associated aberrations known from other neoplasms. The remarkably diverse karyotypic picture of the three squamous cell carcinomas, in particular the finding of unrelated clones in two of them, hints that these neoplasms may be poly-rather than monoclonal. The lack of a common cytogenetic denominator argues that if chromosomal changes are of pathogenetic importance in this tumor type, a wide variety of apparently dissimilar changes exist that are roughly equal in their capacity to malignantly transform skin epithelium.

We have cytogenetically analyzed short-term cultures from an in situ squamous cell carcinoma of the skin (Bowen's disease). The following mosaic tumor karyotype was found: 46,XX, −1, +der(1)(pter→p22::q11→cen→p22:), −9, +der(9)t(1;9)(q11;p24)/46,XX,t(3;6) (q21;p21)/46, XX,t(5;14)(q13;q24),t(7;18)(q32;q11)/46,XX,t(8;11)(p22;q13)/46,XX,t(8;11) (p22;q13),t(15;17) (q13;q24)/46,XX,t(12;15)(q12;p11). None of the rearrangements correspond to previously known cancer-associated abnormalities. Two of the clones are obviously related, and it is reasonable to assume that the t(15;17) developed as an evolutionary change in a cell that already contained t(8;11)(p22;q13). Since five clones without cytogenetic similarities were found in this in situ skin carcinoma, we suggest that the tumor was of polyclonal origin. It is impossible to decide whether all, or indeed any, of the visible abnormalities constitute pathogenetically essential primary changes, or merely represent chromosomal markers of secondary importance in tumorigenesis.

Acta Obstetricia et Gynecologica ScandinavicaVolume 66, Issue 1 p. 41-42 What is the Significance of Koilocytosis in Cervical Intra-Epithelial Neoplasia?: A preliminary retrospective study Lena Sjöstedt, Corresponding Author Lena Sjöstedt Department of Pathology, University of Lund, SwedenDepartment of Pathology University Hospital, S-221 85, Lund, SwedenSearch for more papers by this authorNils Jonsson, Nils Jonsson Department of Pathology, University of Lund, SwedenSearch for more papers by this author Lena Sjöstedt, Corresponding Author Lena Sjöstedt Department of Pathology, University of Lund, SwedenDepartment of Pathology University Hospital, S-221 85, Lund, SwedenSearch for more papers by this authorNils Jonsson, Nils Jonsson Department of Pathology, University of Lund, SwedenSearch for more papers by this author First published: January 1987 https://doi.org/10.3109/00016348709092951Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article.Citing Literature Volume66, Issue1January 1987Pages 41-42 RelatedInformation

Two patients with metastasizing melanoma and diffuse melanosis have previously been reported to excrete large quantities of trichochromes in the urine. The present study describes 2 further melanoma patients with diffuse melanosis and trichochromuria. The hair of one of the patients which had been red in childhood and turned brown in adult age returned to red with the appearance of melanosis. Normal excretion of a methylated melanocytic metabolite, 6-hydroxy-5-methoxyindole-2-carboxylic acid, was observed in this patient, possibly indicating exhaustion of the methylating system. The other patients excreted large quantities of 6-hydroxy-5-methoxyindole-2-carboxylic acid. Both patients showed highly increased excretion of 5-S-cysteinyldopa. Both patients with melanosis exhibited fine electrone-dense granules in lysosomes of dermal histiocytes. The findings support the concept that trichochromes or similar pigments in dermal histiocytes are responsible for diffuse melanosis in melanoma patients.