Trisomy 7 and i(5p) in a transitional cell carcinoma of the ureter

Trisomy 7 and i(5p) in a Transitional Cell Carcinoma of the Ureter In a recent article, Sandberg et al. [1] described a case of transitional cell carcinoma (TCC) of the ureter with trisomy 7 as a sole c h r o m o s o m a l abnormality. They suggested that this a b n o r m a l i t y m a y be associated with TCC of the b l a d d e r and tumors located in the u p p e r urinary tract. We have recently e x a m i n e d the c h r o m o s o m a l constitution of a t u m o r of the left ureter in a 63-year-old female patient. The pathologic diagnosis was TCC grade 2 3 with foci of squamous metaplasia. The t u m o r infiltrated the m u s c u l a r layer of the ureter to a p p r o x i m a t e l y one-third of its thickness. Cytogenetic analysis was performed on p r i m a r y cultures of the t u m o r using p r e v i o u s l y described procedures [2]. The analysis revealed a n e a r - d i p l o i d c h r o m o s o m e n u m b e r and consistent clonal abnormalities that i n c l u d e d trisomy 7, i(5p), and a large submetacentric chromosome of uncertain origin (Fig. 1). Our observations are in agreement with the report of Sandberg et al. regarding occurrence of trisomy 7 in TCC of the ureter. Whether this a b n o r m a l i t y is more often associated with TCC located in the u p p e r urinary tract c o m p a r e d with those in the b l a d d e r is, in our view, uncertain. The n u m b e r of cases analyzed with banding, especially tumors of the ureter, is too small to reach any firm conclusions regarding frequency of particular chromosomal abnormalites. The presence of i(5p) in our case, w h i c h was the most consistent a b n o r m a l i t y in two series of b l a d d e r tumors [2, 3], suggests that this a b n o r m a l i t y occurs in TCC regardless of the anatomical location of the tumor. The presence of trisomy 7 in some cases of TCC is of particular interest because the gene for e p i d e r m a l growth factor (EGF) receptor has been m a p p e d to 7p12-p13. Koprowski et al. [4] have recently d e m o n s t r a t e d that the presence of increased n u m b e r of copies of c h r o m o s o m e # 7 correlates with expression of the receptor for EGF in malignant melanoma. Elevated expression of EGF receptor has been observed in a n u m b e r of t u m o r types, i n c l u d i n g TCC of the b l a d d e r [5]. It will be of interest to learn if trisomy 7 in TCC is related to abnormal expression of EGF receptor. Deregulation of EGF receptor gene s e c o n d a r y to gene-dosage effect m a y be a c o m m o n p h e n o m e n o n occurring in tumors of diverse histogenesis. ZENON GIBAS CONSTANCE A. GRIFFIN BEVERLY S. EMANUEL

Department of Pathology The Medical College of Pennsylvania Philadelphia, PA 19129 Dept. of Pediatrics and Genetics Children's Hospital of Philadelphia Philadelphia, PA 19104

Received September 2, 1986; accepted September 10, 1986.

369 © 1987 Elsevier Science Publishing Co., Inc. 52 Vanderbilt Ave., New York, NY 10017

Cancer Genet Cytogenet 25:369-370(1987) 0165-4608/87/$03.50

370

z. Gibas, C. A. Griffin, and B. S. Emanuel

5 Figure 1

Partial karyotype of the tumor showing i(5p) and trisomy 7.

REFERENCES 1. Sandberg AA, Berger CS, Haddad FS, Kerr D, Hecht F (1986): Chromosome change in transitional cell carcinoma of ureter. Cancer Genet Cytogenet 19:335-340. 2. Gibas Z, Prout GR, Connolly JG, Pontes JE, Sandberg AA (1984): Nonrandom chromosomal changes in transitional cell carcinoma of the bladder. Cancer Res 44:1257-1264. 3. Gibas Z, Prout GR, Pontes JE, Connolly JG, Sandberg AA (1986): A possible specific chromosome change in transitional cell carcinoma of the bladder. Cancer Genet Cytogenet 19:229-238. 4. Koprowski H, Herlyn M, Balaban G, Parmiter A, Ross A, Nowell P (1985): Expression of receptor for epidermal growth factor correlates with increased dosage of chromosome #7 in malignant melanoma. Somat Cell Molec Genet 11:297-302. 5. Gusterson B, Cowley G, Smith JA, Bradford O (1984): Cellular localization of human epidermal growth factor receptor. Cell Biol Intl Rep 8:649-658.