Hereditary predisposition (represented by family antecedents and/or BRCA 1 or 2 mutations) is one of the most important risk factors for breast and ovarian cancer, concerning 5% to 10% of all ovarian cancers.1 In particular, BRCA 1 and 2 genetic mutations are responsible for at least 75% of hereditary cancers of the ovary, with in this case an estimated individual risk at 10% to 40%.2-4 These patients are therefore candidates for appropriate primary preventive care.
Since the 1994 Bethesda Consensus Conference, prophylactic adnexectomy has been recommended in this high-risk group (family antecedents of breast and/or ovarian cancer and/or carriers of BRCA 1 and 2 mutations) after age 35 years or when no further pregnancies are wanted.5
This policy soon allowed the study of excised ovarian material, the macroscopic appearance of which is most often normal. However, careful complete anatomopathological examination of the whole ovary can reveal fine cytological and architectural modifications termed "ovarian dysplasia" and sometimes true occult ovarian cancer is discovered.6,7
The objective of this study was to confirm and detail the histopathology of signs of "ovarian dysplasia" in a comparison of their frequency and degree in a population at genetic risk against a control population.
MATERIALS AND METHODS
Out of a total of 5500 adnexectomies and/or ovarian cystectomies performed between January 1990 and December 2005, we selected 90 patients whom we divided into 2 groups.
- Group A. Bilateral prophylactic ovariectomies for proven genetic predisposition (mutation of the gene BRCA1 or BRCA 2) or family history. The group included 28 patients who had undergone prophylactic adnexectomy following the finding of a mutant BRCA 1 gene (13 patients) or BRCA 2 gene (2 patients), or because of a strong family history of ovarian and/or breast cancer (13 patients). We defined a positive familial history as follows: (1) at least 1 first-degree relative with ovarian cancer and at least 1 first- or second-degree with breast cancer and/or a personal history of breast cancer or (2) at least 2 first- or second-degree relatives with breast cancer with a personal history of breast cancer.
- Group B. Adnexectomies in a control group. First we took a spontaneously fertile population with no personal or family history of gynecological cancer (breast, ovary or endometrium), who had undergone an adnexectomy and/or cystectomy for a benign disorder and in whom histopathological examination indicated healthy ovaries. We then age-matched this cohort to Group A. To reduce the confounding and protective effect of oral contraceptive use, we selected patients for whom the duration of oral contraceptive use was short. Finally, to obtain a better statistical power, we took 2 randomly selected controls for one at-risk patient. Our final control population comprised 62 patients.
Our definition of ovarian atypia is based on earlier studies of ovarian dysplasia. In order for the method to be reproducible, we selected 11 histopathological criteria which are the following: (Figs. 3-12) epithelial multilayering, tufting, surface papillomatosis, nuclear chromatin irregularity, nuclear contour irregularity, cellular pleomorphism, nuclear size, epithelial inclusion cysts, cortical invaginations, psammoma, stromal hyperplasia (Figs. 1 and 2).
In each case, the most abnormal zone was scored from 0 to 2 (0, normal; 1, moderately abnormal; 2, severely abnormal).
A dysplasia score for each patient was simply obtained by summing the scores of all the 11 items (total range, 0-22).
The histopathological slides of the 28 prophylactic ovariectomies and the 62 controls were all read blind by 4 pathologists who were experts in oncogynecology. The average number of slides available for review from the 2 groups was 7.6 (5-11). When several slides were available, the one with the highest dysplasia score was retained. If the pathologists' readings conflicted, then a new reading was made until a consensus was obtained.
Our main measurement was the dysplasia score, with the working hypothesis that the ovaries at genetic risk were associated with a higher dysplasia score than the control ovaries (which would normally have no dysplastic lesions).
Mean comparison of the dysplasia scores of Groups A and B was carried out with the Student t test. The 2 groups were already age-matched. As duration of contraceptive use and parity were quantitative variables, the statistical adjustment will not be taken into account.
By definition, all group A had a family history of cancer; 82% had developed breast cancer at a very young age (44 years on average) with recurrence in 39% of cases. Personal and family history prompted screening for BRAC 1 or 2 gene mutations, which were found in 53.6% of cases (n = 15).
The data concerning parity, duration of use of oral contraceptives, age, and the different types of cancer of each patient when adnexectomy was performed are given in Table 1.
Histopathological analysis found no cancerous tumor in either group (Table 2). We note, however, 1 borderline tumor revealed by histopathology in group A.
The most representative anomalies in group A were epithelial inclusion cysts (100%), tufting (86%), stromal hyperplasia (75%) and epithelial multilayering (68%) (Fig. 1 and Table 3). Conversely, in group B, there were mostly no histopathological anomalies, except for epithelial inclusion kysts, which were present in half the cases (Fig. 2 and Table 3).
Close examination of group A revealed 2 subgroups: carriers of the BRCA mutation (15 patients) and family antecedents without mutation (13 patients): surface papillomatosis, nuclear chromatin irregularity and nuclear contour irregularity, cellular pleomorphism, and cortical invaginations were more frequent with the BRCA gene mutations. The anomalies were generally more marked in the ovaries carrying BRCA mutations. Epithelial inclusion cysts were present in 100% of cases, whether or not mutations were present (Table 3).
From these data, a mean dysplasia score was calculated for group A (prophylactic ovariectomies) by averaging the score of each ovariectomy patient. The mean dysplasia score for the prophylactic ovariectomy patients was 9.67.
In the same way, the mean dysplasia score of group B (controls) was 3.62 (Table 4).
The mean dysplasia score was significantly higher in the prophylactic ovariectomy population than in the control group (9.67 vs 3.62; P < 0.0001). The distinction between BRCA mutation and antecedents with no mutation was apparent in a more severe dysplasia profile for BRCA mutation. Carriers of the genetic mutation had a significantly higher dysplasia score than patients with family antecedents (11.26 vs 8.1; P < 0.0039), despite the fact that in our series, carriers of the genetic mutation made almost 9 times more use of oral contraceptives, which have a protective effect (133 months vs 15 months, respectively; P < 0.0003; Table 5).
Lastly, we note that the mean dysplasia score was somewhat higher for age over 50 years (10.27 vs 8.6; NS; Table 6).
In 1971, Fathalla8 deduced from the higher frequency of ovarian cancer in nulliparous women that ovulation might be implicated in the malignant modification of the ovarian epithelium. One of the physiopathological explanations would be that inclusion cysts (in our study, 100% in group A vs 50% in group B) could result from a natural and physiological process of regeneration after each ovulation, ie, invagination of the epithelial surface cells (in our study, 60% in BRCA mutation carriers vs 17.3% in group A) in the stroma. Because of stroma hyperplasia (in our study, 75% in BRCA mutation carriers vs 16% in group A), the entrapped epithelium could undergo this differentiation process: paracrine influence (hormonal influence through and gonadotrophins, and by the action of cytokins such as interleukins 1 and 6), influence of mitogens stimulating cell proliferation (IL 1 thereby induces the formation of TNF α), and influence of morphogens and/or mutagens of the ovarian cortex (stimulating mutations in surface epithelial cells).9-11
The first histopathological description of ovarian dysplasia was reported in the study of Gusberg and Deligdish12 in 1984. These authors studied the excised material from prophylactic adnexectomy in 3 women whose monozygotic twins had an invasive ovarian cancer.
In all 3 cases, the ovaries were macroscopically normal. However, microscopic analysis revealed various cytological and architectural anomalies: surface papillomatosis, epithelial inclusion cysts, nuclear pleomorphism, epithelial multilayering, and epithelial invaginations.
By analogy with other precancerous lesions of the genital tract, the association of these different anomalies was then termed ovarian dysplasia or ovarian precancerous lesions.13-15
In 1996, Salazar et al16 compared the ovaries of 20 high-risk patients with those of 20 patients with no family antecedents. They also found signs of dysplasia in the prophylactic adnexectomy material from high-risk patients: surface papillomatosis, epithelial multilayering, epithelial inclusion cysts, epithelial invaginations, and stromal hyperplasia, together with 2 cases of occult microinvasive cancers. Although only 9 patients out of 20 had a proven BRCA1 mutation, Salazar et al's study suggested the existence of a precancerous lesion phenotype in both patients with mutation and in patients at high risk because of their family antecedents.
In 1999, Werness et al17 found an isolated increase in the number of epithelial inclusion cysts in their study, carried out blind in 64 prophylactic adnexectomies from high-risk patients compared with 30 controls. In contrast with the study of Salazar et al, other anomalies, such as papillomatosis or stromal hyperplasia, were not found with a greater frequency.
However, even if we find objective evidence of cytological and architectural anomalies in the ovaries of patients at genetic risk, this does not necessarily mean that associations of these modifications have to be considered as dysplastic lesions. These anomalies may merely be unusual but harmless variants of the norm.18-20 How can we be sure they are pathological?
(1) We need to compare ovaries from patients at risk with those from healthy control patients. In our study, the elevated dysplasia score for prophylactic ovariectomy material was statistically significant compared with controls (9.67 vs 3.62, P < 0.0001). We can therefore assert that genetic risk in Group A is associated with histologic abnormalities of the ovary and that these abnormalities are probably the first step of carcinogenesis. These early changes in ovary could be considered as precancerous, ie, "dysplasia."
(2) We need a histopathological dysplasia score that is reproducible and consistent with the literature. There is no consensual dysplasia scoring scheme, the histopathological modifications characteristic of dysplasia being difficult to determine.
Salazar et al,16 using prophylactic ovariectomy material, established an ovarian dysplasia score based on the presence of at least 3 of the following items: epithelial inclusion cysts, epithelial multilayering, surface papillomatosis, deep invaginations, and stromal hyperplasia The score is claimed to have a sensitivity of 75% and a specificity of 90%. The sensitivity is increased by 85% if only 2 items are considered. This score offers the advantage of being simple and reproducible, but it is incomplete and does not allow for the severity of any of the anomalies.
Plaxe et al,21 from a study of apparently healthy ovarian tissue adjacent to stage I ovarian cancers, considered as both necessary and sufficient the presence of the following 4 items for a sound diagnosis of ovarian intraepithelial neoplasia with a sensitivity of 98% and a specificity of 100%, loss of polarity, epithelial stratification, cellular pleomorphism, and irregular distribution of chromatin. Although this score includes the study of nuclear atypia, it is still restrictive and may be biased by the presence of adjacent cancerous tissue.
By contrast, the score of Nieto et al,22 based on a series of oophorectomies subjected to stimulation of ovulation, offers 3 advantages:
- It takes into account the severity of the anomalies by a complete analysis of excised material. The anomaly can be scored as absent (level 0), moderate (level 1), or severe (level 2). This analysis of the whole ovary is delicate as the modifications are very subtle.23
- It is more exhaustive, comprising a total of 9 cytological and architectural anomalies.
- It is underpinned by sound methodology. The score is based on the comparison of an exposed group with a control group with no ovarian neoplasia risk factors, in which it is highly probable that cytological anomalies will be either absent or rare. This statistical comparison with a control group is necessary because there is no threshold score for dysplasia.24
For our study, we adopted and extended the score devised by Nieto et al. We listed the cytological and architectural abnormalities that were most frequent and most representative of ovarian dysplasia after an exhaustive literature review (which also ensured excellent reproducibility and comparability for our study): ovarian dysplasia found in areas adjacent to stage 1 ovarian carcinoma,21,25 in the controlateral ovary of women with stage 1 ovarian carcinoma,26,27 in relation to ovulation induction,22 and in prophylactic oophorectomy for BRCA mutation.16,18,19 We incorporated all of these anomalies in order to have a complete dysplasia scoring system (Table 7).
(3) Moreover, the evidence of ovarian dysplasia distinct from cancerous and normal ovarian epithelium was demonstrated using morphometry and nuclear texture analysis.28,29
Finally, we also found that there was a gradation in the severity of dysplasic lesions. Carriers of the BRCA gene mutation had a significantly higher dysplasia score when there were family antecedents (11.26 vs 8.1; P < 0.0003). Surface papillomatosis, nuclear atypia (nuclear chromatin irregularity and nuclear contour irregularity), cellular pleomorphism, and cortical invaginations seem to be characteristic of BRCA mutation.
Deligdisch et al30 have found that 77.6% of ovaries obtained by prophylactic oophorectomy from women with a genetic predisposition had precancerous changes ("ovarian dysplasia") in the structure of their nuclei, as demonstrated by the morphologic study of nuclear area. Deligdish et al concluded that "this finding strengthens the evidence there is indeed a high risk for the development of ovarian carcinoma in this group of patients." The increased susceptibility to ovarian cancer in the BRCA mutation carriers could be also in accord with the important nuclear atypia (in our study, 73.5% in the BRCA mutation carriers vs 30% in the nonmutation subgroup). This gradation shows that the dysplasia is more marked as the risk is higher, which suggests that the dysplasia is premalignant and that BRCA mutation carriers would have the more possibility of progressing to invasive cancer than nonmutation group. In addition, its greater occurrence in higher age groups suggests that it would be progressive (10.27 vs 8.6).
Moreover, there is a significant difference in the duration of the contraceptive use between the 2 groups. It is well known that the contraceptive use contributes to reduce the risk of ovarian cancer. Duration use of control group is twice as important as duration use in group A, the significance of high dysplasia score in group A is not diminished statistically. However, the duration is obviously long in group A, specially for the BRCA mutation carriers (133 months vs 15 months, P < 0.0003). Although difference in dysplasia score between BRCA mutation carriers and noncarriers is statistically significant, it could be possible that there would be some influence in that group.
One of the limitation of our study is that we did not a histologic sampling of the fallopian tubes: based on the observations that many of the early carcinomas in the BRCA+ women arise in the distal fallopian tube,31,32 there may be in fact more abnormalities than we report. Severe cytological atypia have been described as tufting,, epithelial multilayering, and nuclear atypia.33,34
Systematic and careful examination of both the fimbria and the ovary in larger prospective study would be interesting to establish precisely presence and severity of dysplasia.35
This study (worse dysplasia score between proven mutation and family antecedents alone and worse dysplasia score after age 50 years) suggests abnormalities in ovaries from high-risk women.
It also confirms the utility of systematic fine examination of excised material from prophylactic oophorectomy, which could be extended by molecular biology studies. It confirms the presence of fine cytological and architectural anomalies in at-risk ovaries. The gradation of these anomalies with risk level and with age suggests a progressive step that justifies using the term "ovarian dysplasia" to describe them.
1. Brewer MA, Johnson K, Follen M, et al. Prevention of ovarian cancer: intraepithelial neoplasia. Clin Cancer Res.
2. Bewtra C, Watson P, Conway TA, et al. Hereditary ovarian cancer: a clinicopathological study. Int J Gynecol Pathol.
3. Ford D, Easton DF, Bishop T, et al. Risk of cancer in BRCA 1 mutation carriers. Lancet.
4. Lynch HT, Bewtra C, Lynch JF. Familial ovarian carcinoma. Am J Med.
5. Piver MS, Wong C. Prophylactic oophorectomy
: a century-long dilemma. Hum Reprod.
6. Finch A, Shaw P, Rosen B, et al. Clinical and pathologic findings of prophylactic salpingo-oophorectomies in 159 BRCA1 and BRCA2 carriers. Gynecol Oncol.
7. Schloosshauer PW, Cohen CJ, Penault-Lllorca F, et al. Prophylactic oophorectomy
8. Fathalla M. Incessant ovulation: a factor in ovarian neoplasia? Lancet.
9. Hamilton TC, Godwin AK, Ozols RF. Ovarian carcinogenesis. In Ovarian Cancer.
Paris: Arnette Blackwell, 1996: 21-38.
10. Bershuck A, Kohler MF, Boente MP, et al. Growth regulation and transformation of ovarian epithelium. Cancer.
11. Wong AST, Auersperg N. Ovarian surface epithelium: family history and early events in ovarian cancer. Reprod Biol Endocrinol.
12. Gusberg SB, Deligdish L. Ovarian dysplasia
, a study of identical twins. Cancer.
13. Deligdisch L, Gil J, Kerner H, et al. Ovarian dysplasia
in prophylactic oophorectomy
14. Deligdisch L, Einstein AJ, Guera D, et al. Ovarian dysplasia
in epithelial inclusion cysts. Cancer
15. Deligdisch L. Ovarian dysplasia
: a review. Int J Gynecol Cancer.
16. Salazar H, Godwin AK, Daly MB, et al. Microscopic benign and invasive malignant neoplasms and a cancer-prone phenotype in prophylactic oophorectomies. J Natl Cancer Inst.
17. Werness BA, Afify AM, Bielat KL, et al. Altered surface and cyst epithelium of ovaries removed prophylactically from women with a family history of ovarian cancer. Hum Pathol.
18. Stratton JF, Buckey CH, Lowe D, et al. Comparison of prophylactic oophorectomy
specimens from carriers and non carriers of a BRCA1 or BRCA2 gene mutation. J Natl Cancer Inst.
19. Barakat RR, Federici MG, Saigo PE, et al. Absence of premalignant histologic, molecular, or cell biologic alterations in prophylactic oophorectomy
specimen from BRCA1 heterozygotes. Cancer.
20. Heller DS, Hameed M, Baergen R. Lack of proliferative activity of surface epithelial inclusion cysts of the ovary
. Int J Gynecol Cancer.
21. Plaxe S, Deligdish L, Dottino P, et al. Ovarian intraepithelial neoplasia demonstrated in patients with stage I ovarian carcinoma. Gynecol Oncol.
22. Nieto JJ, Crow J, Sundaresan M, et al. Ovarian epithelial dysplasia in relation to ovulation induction and nulliparity. Gynecol Oncol.
23. Brewer MA, Ranger-Moore J, Baruche A, et al. Exploratory study of ovarian intraepithelial neoplasia. Cancer Epidemiol Biomarkers Prev.
24. Tok EC, Ertung D, Tataroglu C, et al. Clinicopathologic study of the putative precursor lesions of epithelial ovarian cancer in low-risk women. Int J Gynecol Cancer.
25. Zheng J, Wan M, Zweizig S, et al. Histologically or low grade malignant tumors adjacent to high grade ovarian carcinomas contain molecular characteristics of high grade carcinomas. Cancer Res.
26. Mittal KR, Jacquotte AZ, Cooper JL, et al. Controlateral ovary
in unilateral ovarian carcinoma: a search for preneoplastic lesions. Int J Gynecol Pathol.
27. Tressera F, Grases PJ, Labastida R, et al. Histological features of the controlateral ovary
in patients with unilateral ovarian cancer: a case control study. Gynecol Oncol.
28. Deligdisch L, Gil J. Characterization of ovarian dysplasia
by interactive morphometry. Cancer.
29. Deligdisch L, Miranda C, Barba J, et al. Ovarian dysplasia
: nuclear texture analysis. Cancer.
30. Deligdisch L, Gil J, Kerner H, et al. Ovarian dysplasia
in prophylactic oophorectomy
specimens. Cytogenetic and morphometric correlations. Cancer.
31. Medeiros F, Muto MG, Lee Y, et al. The tubal fimbria is a preferred site for early adenocarcinoma in women with familial ovarian cancer syndrome. Am J Surg Pathol.
32. Callahan MJ, Crum CP, Medeiros F, et al. Primary fallopian tube malignancies in BRCA-positive women undergoing surgery for ovarian cancer risk reduction. J Clin Oncol
33. Leunen K, Legius E, Moerman P, et al. Prophylactic salpingo-oophorectomy in 51 women with familial breast-ovarian cancer: importance of fallopian tube dysplasia. Int J Gynecol Cancer.
34. Piek JM, van Diest PJ, Zweemer RP. Dysplastic changes in prophylactic removed fallopian tubes of women predisposed to ovarian cancer. J Pathol.
35. Crum CP, Drapkin R, Kindelberger D, et al. Lessons from BRCA: the tubal fimbria emerges as an origin for pelvic serous cancer. Clin Med Res.