Cytogenetic studies of endometrial malignancies

Cytogenetic Studies of Endometrial Malignancies Athena Milatovich, Nyla A. Heerema, and Catherine G. Palmer

ABSTRACT: Thirty cases of endometrial malignancy were successfully studied cytogenetically. Twentyfour of the cases were endometrial adenocarcinomas. Twenty-three of these were stage I tumors, and the twenty-fourth was a stage IV tumor. Fourteen of the stage I adenocarcinomas had abnormal chromosomes, and nine had apparently normal chromosomes. No two tumors had an identical chromosomal rearrangement. Trisomy lq was common however; 10 of the 14 tumors with abnormal chromosomes had a chromosome I abnormality. Clinical and pathologic data were available for 17 of these patients. There appeared to be no relationship between prognostic indicators and the tumor karyotype except for uterine size. Six cases of endometrial malignant mixed mfdlerian tumor (MMMT) of the homologous type were also analyzed cytagenetically. Three of these tumors had very abnormal karyotypes, and the remaining three had apparently normal chromosomes. Structural abnormalities of chromosome 1, 3, and 5 were present in all three tumors with abnormal karyatypes, but identical breakpoints or rearrangements were not observed.

INTRODUCTION Although endometrial adenocarcinoma is a very common form of gynecologic cancer, there are few cytogenetic studies of these tumors. The three largest studies to date are of six, seven, and eight cases of endometrial adenocarcinoma, respectively [1-3]. Trisomy or tetrasomy for l q is c o m m o n in this tumor type, as are apparently normal karyotypes. Approximately 30 cases of primary stage I endometrial adenocarcinoma with chromosomal abnormalities and banded karyotypes have been reported. This report adds 14 cases. In addition to the 24 endometrial adenocarcinomas studied, six cases of endometrial malignant mixed mfillerian tumors (MMMTs) were also analyzed cytogenetically. There are basically three types of endometrial malignancies: carcinoma in situ, adenocarcinoma (which has m a n y variant forms), and uterine sarcoma. Uterine sarcomas are a group of rare tumors that account for 1-5% of uterine malignancies. These tumors are classified as leiomyosarcomas, endometrial stromal sarcomas, MMMTs of the homologous type, MMMTs of the heterologous type, and a miscellaneous group of other uterine sarcomas [4]. Endometrial MMMTs of the homologous type, like the tumors i n this study, consist of a carcinoma and at least one type of sarcoma. These associated sarcomas are either leiomyosarcoma, stromal sarcoma, or fibrosarcoma, or some mixture of these types. Cytogenetic reports of endometrial MMMTs are few; of these, two reports are of c o n t i n u o u s cell lines [5, 6]. From the Departmentof MedicalGenetics, Indiana UniversitySchoolof Medicine,Indianapolis,Indiana. Address reprint requests to: Catherine G. Palmer, Ph.D., Department of Medical Genetics, Cytogenetics Laboratory, 975 West Walnut Street, Indianapolis, IN 46202-5251. Received June 21, 1989; accepted September 12, 1989.

41 © 1990 Elsevier Science PublishingCo., Inc. 655 Avenueof the Americas, New York, NY 10010

Cancer Genet Cytogenet 46:41-54 (1990)

0165-4608/90/$03.50

42

A. Milatovich et al.

MATERIAL AND METHODS Pieces of tumors were collected in transport medium (RPMI 1640, McCoy's 5A, or Ham's F-/0) and received within a few hours of surgery. Tumors were minced, and half of each was enzymatically treated with a 0.4% mixture of collagenase III (Cooper Biomedical Malvern, PA) and Dispase (Boehringer-Mannheim Indianapolis, IN) for 1-4 hours at 37°C with shaking. The other portion was not enzymatically treated and the pieces were cultured. Both portions were treated in parallel. Cytogenetic analyses were performed on direct and overnight suspension cultures of each after 4.5- and 16-hour Colcemid treatment, respectively, at a final Colcemid concentration of 0.6 /~g/ml. Short-term cultures were harvested at 5-9 days of culture, also with a final colcemid concentration of 0.6/zg/ml. A hypotonic solution of KC1, EGTA, and HEPES was used [7]. Slides were made immediately after harvesting and stained with Wright stain. RESULTS

Endometrial Adenocarcinomas

Cytogenetic findings. Table 1 shows the cytogenetic results of the 24 endometrial adenocarcinomas in this study (23 stage I tumors and I stage IV tumor). Fifteen tumors had abnormal karyotypes and nine tumors had apparently normal karyotypes. Six of the nine tumors with normal chromosomes were examined on direct preparations; the other three were analyzed after short-term culture only. Direct and overnight cultures were performed on all 24 samples. Short-term cultures were harvested at 5-9 days. Six samples were evaluated in this way. Table 2 shows the results of these techniques. Seven of the 24 samples had only abnormal karyotypes on the direct and overnight cultures. Four of the 24 samples had both normal and abnormal metaphases on the direct cultures, and two samples had both normal and abnormal metaphases on the overnight cultures. Two of the six samples studied by short-term culture had only abnormal chromosomes, whereas one sample was normal on short-term culture but abnormal on direct and overnight culture. Of the 15 adenocarcinomas with chromosomal abnormalities, chromosome 1 abnormalities were very common and were noted in 10 of the 14 stage I tumors. These were t(1;3)(q21;q29), der(1)t(1;15)(p13;q11.2), der(16)t(1;16)(q21;q13) and del(1)(p35 or p36) [cases 2, 3, 6, and 20, respectively], each noted as the sole chromosomal abnormality in these four tumors. In addition, two tumors had a limited number of chromosomal abnormalities but had chromosome I involved as well. One tumor (case 7] had t(1;9)(q4?1;q13), der(11)t(11;?)(q13;?) and der(22)t(22;?)(q13;?); the other [case 19] had der(22)t(1;22)(q12;p11.2) and was also trisomic for chromosomes 7 and 10. Three tumors had near-triploid numbers of chromosomes. One [case 22] had a modal number of 64, another [case 23] had a range of 51-78 chromosomes, and a third [case 17] had both normal diploid cells as well as a modal number of chromosomes of 76 with several markers. Another tumor [case 21] had at least seven markers, but a near-diploid number of chromosomes. These four tumors all had chromosome 1 abnormalities as well as numerous other chromosome aberrations. The chromosome 1 aberrations in these four tumors were der(1)t(?;1;?)(?;p36->q44;?) and der(1)t(?;1;?)(?;p36-~q21;?) in one tumor [case 22], der(1)t(1;?)(p36;?) in another [case 23], der(1)t(1;?)(q44;?) in the third [case 21] and der(1)t(1;?)(p3?6;?) in the last [case 17]. Four cases also had abnormalities of other chromosomes. These included one tumor [case 12] with trisomy 10, one [case 16] with a small marker, another [case 18]

16 3 4 9 5 8 17 5 30 8 33 37 20 31 5 42 10 34 39 18 12 7

13

35

1 2 3 4a 5a 6 7 8a 9 10 11 12 13 14 15 16 17 18 19 20 21 22

23

24 h

Abbreviation: NA, not available.

b Stage IV tumor,

"From short-term cultures only.

No. of metaphases

?

51/78

46 ? 46 48 46 46 46 46 46 46 48 47 46 48 46 46/47 48/76 46 48 46 45 64

Modal no. of c h r o m o s o m e s C h r o m o s o m a l abnormalities t(12;lZ)(q13;q22) t(1;3)(q21;q29) der(1)t(1;15)(p13;q11.2) None None der(16)t(1;16)(q21;q13) t(1;9)(q4?1;q13),der(11)t(11;?](q13;?),der(22)t(22;?)(q13;?) None None None None +10 None None None + mar der(1)t(1;?)(p3?6;?) de~(6)(q23) + 7, + 10,der(22)t(1;22)(q12;p11.2) del(1)(p35 or p36) der(1)t(1;?)(q44;?),del(12)(p12), + 7 m a r + 4, + 5, + 12, + 13, + 20, + X,der(1)t(?;1;?)(?;p36--~q44;?),der(1)t(?;1;?) (?;p36-~q21;?),del(3)(q13),del(6)(q21),del(7)(q22),der(10)t(8;10) (q12;p11.2),der(12)t(12;?)(q13;?),del(12)(q12),der(15)t(15;?)(p11;?), + 3 mar der(1)t(1;?)(p36;?),del(3)(p12),der(5)t(5;?)(p15;?),der(6)t(1;6) (q21;q15),der(7)t(7;?)(p22;?),i(8q),del(9)(q12),i(12q), der(21)t(21;22)(p11;p11),der(22)t(22;?)(p11;?) der(1)t(1;?)(p36;?),del(3)(p14),i(6p),del(7)(p21),der(11)t(11;?) (p14;?),der(16)t(16;?)(p13;?),der(19)t(19;?)(p13;?), + m a r

C y t o g e n e t i c r e s u l t s of e n d o m e t r i a l a d e n o c a r c i n o m a s

Case

Table 1

CO

44

A. Milatovich et al.

Table 2

Comparison of culturing techniques and chromosome results Direct

Case 1 2 3 6 7 12 16 17 18 19 20 21 23 24

Normal . . . 0 0 0 23 0 20 0 12 0 1 0

Overnight

Abnormal . . .

. . . 7 14 28 1 8 8 39 7 38 11 28

Normal

Short-term cultures

Abnormal

. . .

Normal

Abnormal

Days 9 8 8

---

16 2 4 ---

6

0

5

1 0 0 0 11 1 6 0 3 0 0 0

1 3 9 2 1 0 5 0 9 3 7

Dash indicates a culture failure.

with a del(6)(q23) and a fourth [case 1] with an apparently balanced t(12;12)(q13;q22). The only recurrent abnormality, also reported in the literature, was trisomy 10, previously reported in 11 cases [1-3, 8-10] and found in two cases in this study. A representative karyotype of one endometrial adenocarcinoma [case 19] is s h o w n in Fig. 1. The inset shows a partial karyotype that better illustrates the translocation.

Correlation to clinical parameters. A comparison of our cytogenetic results with available clinical and pathologic data is shown in Table 3. Prognosis in endometrial adenocarcinoma is usually determined by stage, pathologic diagnosis, histologic grade or differentiation, depth of myometrial invasion, cytology of pelvic washings, l y m p h node biopsy results, presence of adnexal masses, uterine size, and age at diagnosis. In this study, all of these prognostic indicators were considered in 17 of 23 cases of stage I endometrial adenocarcinoma. The tumors were divided into two groups: those with abnormal karyotypes and those with apparently normal karyotypes. Grade, depth of myometrial invasion and age did not appear to be correlated to the cytogenetic findings. Cytology of pelvic washings and lymph node biopsies were usually negative. Only one case had both indicators positive and also had apparently normal chromosomes whereas another case had positive cytology results and an apparently normal karyotype. Adnexal masses were present in five cases. Only one of these cases had an apparently normal karyotype, whereas four cases had chromosomal abnormalities (two had structural abnormalities only, and three had abnormalities of chromosome 1). Only uterine size of the patient appeared to be correlated to the chromosomal findings of the tumor. Six of the eight patients whose tumors were chromosomally abnormal had an increased uterine size, whereas only two of the n i n e patients whose tumors were apparently chromosomally normal had an increased uterine size. This difference was not statistically significant, however, (not significant, X 2 = 1.8 and 1.0 at p -< 0.1). Endometrial M a l i g n a n t Mixed Mffllerian Tumors

Cytogenetic findings. The cytogenetic results of the endometrial MMMTs are shown i n Table 4. Three of these tumors had extremely abnormal karyotypes with no identical abnormalities. The chromosomal breakpoints in the clonal structural abnormalities,

stage I stage I stage I stage IB stage I

A d e n o c a r c i n o m a , stage IB A d e n o c a r c i n o m a , stage I A d e n o c a r c i n o m a , stage IB A d e n o c a r c i n o m a , stage IA Adenosquamous carcinoma A d e n o c a r c i n o m a , stage IB A d e n o c a r c i n o m a , stage I Carcinoma Adenocarcinoma A d e n o c a r c i n o m a , stage IA Adenosquamous carcinoma, stage I A d e n o c a r c i n o m a , stage IB

Abbreviations: NA, not available; SI. slightly.

15

None

t(1;16) t{1;9), der(11}, der(22) M N = 76, der(1} del(6) + 7 , + 10, t(1;22) None None None None None None None None

17 18 19 4 5 8 9 10 11 13 14

t{1;15)

3

Adenocarcinoma, Adenocarcinoma, Adenocarcinoma, Adenocarcinoma, Adenocarcinoma,

Pathologic d i a g n o s i s

Well

Moderately Well Poorly Moderately Moderately Poorly Well Moderately Moderately Moderately Moderately

Well Well Well Moderately Moderately

Differentiated

10 mn~115 m m

None 6 mm/21mm 7 rand21 m m 11 m m / 2 3 m m 10 m m / 2 0 m m 19 m m / 2 0 m m None 6 mm/17 mm 14 m m / 1 9 m m 10 m m / 1 1 m m 5 mm/lO mm

None None 19 m m / 2 0 m m 10 mrrg20 m m None NA + NA + -

NA NA NA -

Cytology

adenocarcinoma

Myometrial invasion

o f c y t o g e n e t i c w i t h p a t h o l o g i c f i n d i n g s of e n d o m e t r i a l

6 7

t(12;12) t(1;3)

Chromosomal abnormalities

Case #

1 2

Comparison

Table 3

+ NA + -

NA -

Lymph nodes

None

Yes Yes Yes None None None None None None Yes None

None Yes None None None

Adenexal masses

S1. large

Large S1. large Normal Normal Normal Normal Large Normal Normal Normal Small

Large Large Large Normal S1. large

Uterine size

81

62 53 67 50 65 43 43 72 59 72 68

56 55 56 74 55

Age

44

42

22 30 27

5

25 a

26

27 28 b 29

30

46

46 46 72

57

63

Modal no. of c h r o m o s o m e s Structural aberrations

der(1)t(?;1;1?)(?::p36.2-+q44::?),der(1)t(1;?)(p36.1;?),del(2)(q21q23), der(3)t(3;?)(p21;?),der(5)t(?;5;?)(?;p13-~q11.l::q13;?),del(8)(q22), 2der(9)t(9;?)(p24;?),der(10)t(10;?)(q26;?),2der(12)t(12;?)(q13;?), der(12)t(?;12;?)(?;p12--~q22;?),der(13)t(13;?)(p11.1;?),2der(14)t(14;?) (p11.1;?),2der(14)t(14;?)(p11.1;?),2der(16)t(16;?)(q11.2;?),2der(17)t(17;?) (q25;?),2del(19)(p13.2),2der(20)t(20;?)(q13.2;?),der(22)t(22;?)(p11.1;?), + mar der(1)t(1;?)(p36;?),del(1)(p21),del(3)(pl 2),der(3)t(3;?)(q29;?), del(5)(p13),del(6)(p22),del(6)(q21),i(6p),der(11)t(11;?)(p15 ;?), der(17)t(17;?)(q24;?),der(19)t(19;?)(q13 ;?), + m a r None None der(?)t(1;1;?)(q21;q21;?) or der(?)t(1;?)(q21;?),der(3)t(3;?)(p13;?), del(5)(q13q31),der(5),der(9)t(9;?)(q21;?),der(10),der(?)t(11;?) (q13;?),der(13)t(13;?)(p11;?),der(14)t(14;?)(q32;?), + 3 m a r None

a Ascitic tumor. b From short-term cultures only. All data show clonal abnormalities that occurred in nearly every metaphase examined.

No. of metaphases

Cytogenetic results of endometrial malignant mixed mfillerian tumors

Case

Table 4

47

Cytogenetic Studies of Endometrial Malignancies

1

der{221 L

1

2

5

V 7

8

13

14 ¸

19

20

9

15

i0

16

21

22

'

.... i..i

12

17

18

Sex Chromosomes Case 19

Figure I A representative karyotype of case 19, a stage I endometrial adenocarcinoma. Inset, partial karyotype of the same case shows translocation. as well as the chromosomal breakpoints of the partially identified markers, are shown in Table 5. A breakpoint at l p 3 6 was observed in two of the three tumors (MMMTs) with abnormal karyotypes, as were 1 3 p l l and 17q24 or q25. Chromosomes 1, 3, and 5 were involved in structural rearrangements in all three of the tumors that had abnormal chromosomes. Three other tumors of this type had apparently normal karyotypes. Two of these were analyzed from direct preparations, and the third was analyzed from short-term cultures. Figure 2 is a representative karyotype of a case of endometrial MMMT (case 25) with abnormal cytogenetic findings. DISCUSSION This study is the largest study to date of primary tumors of stage I endometrial adenocarcinoma. The only consistent chromosomal abnormality in this series appeared to be trisomy or tetrasomy of lq. This finding was present in 71% of our cases

1

q21 p36 q21 p36

p14

p12

p15

q13q31

p13 q11.1 q13 p13

5

qll

q15

q21

q2?3

p22 q21 qll

6

a Endometrial malignant mixed miillerian tumors.

24

23

q44

q12 p35/36 q44 p36

q13

q29

q21 p13 q21 q4?1 p3?6

2 3 6 7 17 18 19 20 21 22

p12 q29

p21

3

p13

q21q23

2

29a q21 1

25 a p36.1 p36.2 q44 26a p21 p36

Case

p21

p22

q22

7

pll

q12

q22

8

q12

q13

q21

p24

9

p11.2

q26

10

Table 5 Chromosome breakpoints in endometrial malignancies

p14

q13

q13

p15

11

pll

p12 q12 q13

q13 q22

p12 q13 q22

12

Chromosome

pll

p11.1

13

q32

p11.1

14

pll

q11.2

15

p13

q13

q11.2

16

q13

q24

p13

p13.2

19

q25

17

q13.2

20

pll

21

p11.2

q13

p11.1

22

Qo

49

Cytogenetic Studies of Endometrial Malignancies

Y

V

2

1

Y

3

4

V VV

V 6

8

7

9

vv, v 13

5:!

14

16

15

2O

21

°

22

12

V

VV

VV 19

ll

i0

17

18

% i

Marker

sex Chromosorres

Case 25

Figure 2 A representative karyotype of case 25, an endometrial malignant mixed mfillerian tumor of the homologous type. with chromosomal abnormalities and in approximately 75% of the reported cases. Table 6 shows the abnormalities of chromosome 1 both in this study and in the previously reported cases [1-3, 8-15, 17, 18] and the trisomic or tetrasomic segment of chromosome I in the tumor. Of the 24 reported cases with chromosome I abnormalities, only i(lq) has recurred in seven reported cases [1-3, 8, 9]. This suggested a possible relationship between chromosome 1 and early stages of endometrial adenocarcinoma. Six of the 10 stage I cases in this study with chromosome 1 abnormalities had an excess of the lq, in particular, 1q21-qter. An excess of lq, or, specifically 1q21-qter, is also apparent in the reported cases shown in Fig. 3 and Table 6. This finding agrees with the suggestion of Whang-Peng et al. [18] of the relationship of 1q21-qter to neoplastic transformation. Whang-Peng et al. [18] reported specific regions of chromosome 1 that appeared to be involved in particular neoplasms: 1q25-q32 was most often involved in hematologic disorders, lq23-25 in myeloproliferative disorders, and 1q21-q25 in breast and colon cancer. Abnormalities of chromosome 1 are frequently observed in solid malignancies. Brito-Babapulle and Atkin [19] surveyed 343 breakpoints that led to chromosome 1 abnormalities in 218 human neoplasms and found that 49.9% were located in or near the C-heterochromatic region. There were also smaller clusters of breakpoints, with

50

A. Milatovich et at.

Table 6

Endometrial adenocarcinomas with chromosome 1 abnormalities

Reference

Chromosome 1 abnormality

[11] [12] [13] [1]

del(1)(q42) t(lq;9), + lp, der(lq) t ( l q - ; + ?)(qter-~q21 or q12::?) + del(1)(p21) + tdic(1;16)(p21;q24) + i(lq) + del(1)(p21), + del(1)(p21) + i(lq) + der(lq16p)t(1;16)(lp16q;lq16p) + der(21)t(1;21)(ql 1;p13) + der(lq21q)t(1;21)(lp21p;lq21q) + i(lq) + dir dup(1)(q21-~q31) + i(lq) t(1;5)(p13;q12), + del(1)(pl3) der(11)t(1;11)(q21;q23), + lq t(1;?) + i(lq) ins(lp) + der(8)t(1;8)(q12;p11.1) + i(lq) + i(lq) - 1, + r(1), + del(1)(p13) + del(1)(p21), + del(1)(p33) t(1;3)(q21;q29) + der(1)t(1;15)(p13;q11.2) + der(16)t(1;16)(q21;q13) t(1;9)(q4?1;q13) + der(1)t(1;?)(p36;?) + der(22)t(1;22)(q12;p11.2) del(1)(p35 or p36) + der(1)t(1;?)(q44;?) + der(1)t(?;1;?)(?;p36--*q44;?), + der(1)t(?;1;?)(?;p36-~q21;?) + der(1)t(1;?)(p36;?), + der(6)t(1;6)(q21;q15) + der(1)t(1;?)(p36;?)

[2]

[8] [14] [10] [15] [9] [17] [3]

[18] Present study

Trisomic/tetrasomic 1 NA lp,lq NA 1p21--~1qter 1p21--~1qter lq 1p21--~1qter lq lq lqll-~lqter lq lq 1q21---~1q31 lq lpl3--~lqter 1q21--~1qter NA lq NA 1q12--~1qter lq lq 1p13--~1qter 1p33--~1qter None 1p13--~1qter 1q21--~1qter None lp36--~1qter 1q12--~1qter None 1pter--~1q44 1p36-~1q44, 1p36-*1q21 1p36--~1qter, 1q21--~1qter 1p36---~1qter

Abbreviation: NA, not available.

14.3% at 1q31-q32, 14.6% at 1 p 2 2 - p 3 2 , and 8.2% at lp36. Although chromosome 1 abnormalities are frequently observed in solid tumors, as well as in leukemias, they are generally believed to represent secondary changes, as they occur frequently and nonspecifically [20]. Because the abnormalities of chromosome 1 in e n d o m e t r i a l a d e n o c a r c i n o m a s are frequently the sole chromosomal aberration, they probably represent the p r i m a r y change. Mitelman and Helm [21] reoorted that l p l l was one of the three most c o m m o n breakpoints in malignant epithelial neoplasms and listed eight oncogenes on c h r o m o s o m e 1, two of w h i c h are located on l q and m a y be involved in e n d o m e t r i a l adenocarcinoma. These are SKI and ARG, located at 1q21.1-q24 and lq25, respectively. Table 5 also lists the breakpoints observed in the endometrial adenocarcinomas in this study. Recurrence of chromosome 1 abnormalities is evident. Dutriltaux and Couturier [8] s t u d i e d 16 cases of stage I endometrial adenocarcinoma: l q was involved

Cytogenetic Studies of Endometrial Malignancies

51

THIS STUDY

REPORTED CASES

1 Figure 3 cinoma.

Areas of chromosome 1 that are trisomic or tetrasomic in endometrial adenocar-

in 11 of the 16 cases examined, trisomy 10 in six of the cases, and trisomy 2, trisomy 7, and monosomy of Xp in three cases each. Monsomy for Xq, trisomy for 3q, and trisomy for Xq were observed in two cases each. In our study, 10 cases had chromosome I abnormalities, six of which had an excess of lq, one case had trisomy 10, and another case had trisomy for 7 and 10 and a t(1;22). Although in endometrial adenocarcinoma abnormalities of chromosome I are quite common, in 30% of these stage I tumors the chromosomes are apparently normal, both in this study and in the reported cases [22]. Couturier et al. [3] believed that these normal cells were representative of the malignancy. They gave as an example one case of clonal evolution of an abnormal 1 that also had normal chromosomes in some metaphases. They proposed that endometrial adenocarcinomas are chromosomally normal malignancies that progress and develop chromosomal abnormalities. Sandberg et al. [23] reported that the cytogenetically normal cells are probably the stromal cells that are part of the tumor or, that although they appeared normal, " . . . the changes are beyond the resolution of cytogenetic techniques presently used." The

52

A. Milatovich et al. metaphases that appeared to be normal may have been representative of the normal stromal and epithelial cells. Although the malignant cells may have been present and possibly karyotypically abnormal, they were not cytogenetically observed owing to the low mitotic index of the malignant cells, the overgrowth of the normal cells, or both. Our data on normal cells in direct and cultured preparations of these tumors are insufficient to resolve this question. The relationship of clinical and pathologic data to the cytogenetic findings of these tumors was also considered. There appeared to be no relationship beween the cytogenetic results and age, grade, stage, and depth of myometrial invasion. All three of the larger studies [1-3] attempted to correlate histologic grade, clinical stage, and age with cytogenetic results. The two latter studies [2, 3] also included depth of myometrial invasion. Fujita et al. [1] reported no differences between the number and type of chromosomal abnormalities of tumors that were stage I and tumors of later stages (when stage was reported). When age was considered as a prognostic indicator, the patients were divided into two groups: age 30-60 years and older than 60 years. There appeared to be no correlation of these parameters with the cytogenetic data in these studies [1-3]. When the patients in our study were divided into two groups--those whose tumors had abnormal karyotypes and those whose tumors had apparently normal karyotypes--only uterine size was associated with the cytogenetic results. Uterine size may be construed as simply reflecting the size or spread of the malignancy, as it is one of the factors used to estimate prognosis. Jones [24] compared 5-year survival to uterine size at diagnosis: 84.5% of patients with a uterus of normal size survived, but only 66.6% of patients with an enlarged uterus survived. The preliminary data in this study suggest that a link may exist between uterine size and the presence/absence of chromosomal aberrations in these tumors. More cases of stage I endometrial adenocarcinoma must be analyzed and compared with available clinical and pathologic data to confirm this association. In addition to the stage I endometrial adenocarcinomas in this study, cytogenetic analyses of six cases of endometrial MMMTs are described. These are very rare malignancies. Cytogenetic reports of endometrial MMMTs are few, and of these two reports were of continuous cell lines. The MES-SA cell line [5] had a t(5;6) and numerical abnormalities, and the RJ-984 cell line [6] had a 46,XX,t(11;16) karyotype. A third case, a mixed mesodermal tumor [1], was reported to have a modal chromosome number of 56 and clonal abnormalities that included an i(14q) and a 16p +, but further detailed cytogenetic findings were not provided. Of the six cases in this study, three were very abnormal chromosomally and the other three tumors were apparently normal cytogenetically. The three tumors in this study that have very abnormal chromosomes have karyotypes comparable to other tumors of much later stages (such as the stage IV endometrial adenocarcinoma we report, case 24, Tables 1 and 4). They have very complex karyotypes with many unidentified markers. Although no two samples had apparently identical structural abnormalities, all three cases did have abnormalities of chromosomes 1, 3, and 5. Two cases have lp36 breakpoints in common. All three of our cases have breakpoints in the 3p, namely 3p12, 3p13, and 3p21. Abnormalities of chromosome 3 have been reported in mixed salivary gland tumors [t(3;8)(p12;q12)], benign lipomas [t(3;12)(q28;q14)], lung adenocarcinomas [del(3)(p14q23)], and kidney adenocarcinomas [del(3)(p21)]. Two of our three cases of endometrial MMMTs also have deletions of chromosome 5; del(5)(p13) and del(5)(q13q31). Chromosome 5 abnormalities have been reported in bladder adenocarcinomas [i(Sp)] and secondary leukemias [del(5)(q13q33)] [23]. Case 25, an ascitic tumor, had a marker that appeared to resemble an i(12p). Isochromosome 12p has been described in tumors of germ cell origin [25] and in both an ovarian MMMT and a dysgerminoma [26]. Further investigation of metaphases with higher resolution showed, however, that the marker was a der(12)t(12;?)(q13;?) and not an i(12p).

Cytogenetic Studies of Endometrial Malignancies

53

Owi n g to the quality of the preparations examined in this and other studies, apparent i s o c h r o m o s o m e s such as the i(12p) must be studied by molecular means for firmer establishment of their identity. A m o n g endometrial tumors, chromosomal abnormalities of some endometrial MMMTs of the homologous type apparently have very complex karyotypic abnormalities and stage I endometrial adenocarcinomas apparently have " s i m p l e " karyotypes with near-diploid numbers of chromosomes and few structural rearrangements.

This research was supported in part by a grant from the Marion County Cancer Society, Inc., the Little Red Door. The authors thank Drs. Gregory P. Sutton and Robert Bigsby of the Department of Obstetrics and Gynecology at Indiana University Medical Center, as well as the Cooperative Human Tissue Network, for providing the samples and clinical and pathologic data necessary for this study.

REFERENCES 1. Fujita H, Wake N, Kutwuzawa T, Ichinoe K, Hreshchyshyn MM, Sandberg AA (1985): Markar chromosomes of the long arm of chromosome 1 in endometrial carcinoma. Cancer Genet Cytogenet 18:283-293. 2. Couturier J, Vielh P, Salmon R, Dutrillaux B (1986): Trisomy and tetrasomy for long arm of chromosome 1 in near-diploid human endometrial adenocarcinomas. Int J Cancer 38:17-19. 3. Couturier J, Vielh P, Salmon R], Lombard M, Dutrillaux B (1988): Imbalance in endometrial adenocarcinoma. Cancer Genet Cytogenet 33:67-76. 4. DiSaia PJ, Creasman WT (1989): Clinical Gynecologic Oncology, 3rd Ed. CV Mosby, St. Louis, pp. 164-213. 5. Harker WG, MacKintosh FR, Sikic BI (1983): Development and characterization of a human sarcoma cell line, MES-SA, sensitive to multiple drugs. Cancer Res 43:4943-4950. 6. Centola GM, Marchetti DL, Kaufman L, Mitter NS (1987): Mixed mesodermal tumor of the uterus (RJ-984). Case report and in vitro study. Gynecol Oncol 26:140-147. 7. 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. 8. Dutrillaux B, Couturier J (1986): Chromosome imbalance in endometrial adenocarcinomas. A possible adaptation to abnormal metabolic pathways. Ann Genet 29(2):76-81. 9. Gibas Z, Rubin SC (1987): Well-differentiated adenocarcinoma of endometrium with simple karyotypic changes. A case report. Cancer Genet Cytogenet 25:21-26. 10. Yoshida MA, Ohyashiki K, Piver SM, Sandberg AA (1986]: Recurrent endometrial adenocarcinema with rearrangement of chromosomes 1 and 11. Cancer Genet Cytogenet 20:159-162. 11. van der Riet-Fox MF, Retief AE, van Niekerk WA (1979): Chromosome changes in 17 human neoplasms studied with banding. Cancer 44:2108-2119. 12. Gal D, Forney JP, Dev VG, Porter JC (1982): A new human cell line derived from a poorly differentiated endometrial adenocarcinoma. Gynecol Oncol 13:50-57. 13. Kusyk CJ, Turpening EL, Edwards CL, Wharton JT, Copeland LJ (1982): Karyotype analysis of four solid gynecologic tumors. Gynecol Oncol 14:324-338. 14. Musilova J, Michalova K (1986): Cytogenetic study of cancer cells in effusions. Cancer Genet Cytogenet 19:271-279. 15. Crickard K, Crickard U, Yoonessi M (1987): Establishment and characterization of two human endometrial adenocarcinoma cell lines on extracellular matrix (ECM). Proc AACR 28:31. 16. Pritchard ML, Haydock SW, Sachdeva R, Noumoff J (1987}: Characteristics of an endometrial adenocarcinoma cell line, HEC-1A. Proc AACR 28:31. 17. Horgas G, Grubisic G, Spaventi S (1988): Trisomy and tetrasomy of the long arm of chromosome 1 in a direct preparation of human endometrial adenocarcinoma. Cancer Genet Cytogenet 35:269-272. 18. Whang-Peng J, Knutsen T, Douglass EC, Chu E, Ozols RF, Hogan WM, Young RC (1984). Cytogenetic studies in ovarian cancer. Cancer Genet Cytogenet 11:91-106.