Serous borderline (low malignant potential, atypical proliferative) ovarian tumors: Workshop perspectives

Borderline ovarian tumour: pathological diagnostic dilemma and risk factors for invasive or lethal recurrence

By comparison with ovarian carcinomas, borderline ovarian tumours are characterised clinically by superior overall survival, even in women with peritoneal spread. In this Review, we aimed to clarify the histological and clinical factors potentially defining a high-risk group in whom disease is likely to evolve to invasive disease. Invasive peritoneal implants (in serous borderline ovarian tumours) and residual disease after surgery were the two factors clearly identified. Other factors are controversial owing to increased risk of invasive recurrence: micropapillary patterns in serous borderline ovarian tumour, intraepithelial carcinoma in mucinous lesions, stromal microinvasion in serous lesions, and use of cystectomy in mucinous borderline ovarian tumours. The pathologist has a pivotal role in assessment of the borderline nature of ovarian tumours and in identification of high-risk criteria, most of which are histological. But, reproducibility of the histological interpretation of some of these potential criteria--eg, classification of peritoneal implants (particularly in desmoplastic subtype), stromal microinvasion, micropapillary patterns, and intraepithelial carcinoma in mucinous borderline ovarian tumours--remains unclear, and should be investigated.

Ovarian serous carcinoma: recent concepts on its origin and carcinogenesis

Recent morphologic and molecular genetic studies have led to a paradigm shift in our conceptualization of the carcinogenesis and histogenesis of pelvic (non-uterine) serous carcinomas. It appears that both low-grade and high-grade pelvic serous carcinomas that have traditionally been classified as ovarian in origin, actually originate, at least in a significant subset, from the distal fallopian tube. Clonal expansions of the tubal secretory cell probably give rise to serous carcinomas, and the degree of ciliated conversion is a function of the degree to which the genetic hits deregulate normal differentiation. In this article, the authors review the evidentiary basis for aforementioned paradigm shift, as well as its potential clinical implications.

Ovarian carcinomas: five distinct diseases with different origins, genetic alterations, and clinicopathological features

Malignant epithelial tumors (carcinomas) are the most common ovarian cancers and also the most lethal gynecological malignancies. Based on histopathology and molecular genetic alterations, ovarian carcinomas are divided into five main types (high-grade serous (70%), endometrioid (10%), clear cell (10%), mucinous (3%), and low-grade serous carcinomas (<5%)) that account for over 95% of cases. These types are essentially distinct diseases, as indicated by differences in epidemiological and genetic risk factors, precursor lesions, patterns of spread, and molecular events during oncogenesis, response to chemotherapy, and prognosis. For a successful specific treatment, reproducible histopathological diagnosis of the tumor cell type is critical. The five tumor types are morphologically diverse and resemble carcinomas of the uterus. Actually, recent investigations have demonstrated that a significant number of cancers, traditionally thought to be primary ovarian tumors (particularly serous, endometrioid, and clear cell carcinomas), originate in the fallopian tube and the endometrium and involve the ovary secondarily. This review summarizes recent advances in the molecular pathology which have greatly improved our understanding of the biology of ovarian carcinoma and are also relevant to patient management.

Borderline ovarian tumors diagnosed during pregnancy exhibit a high incidence of aggressive features: results of a French multicenter study

BACKGROUND

The purpose of the current study was to evaluate the characteristics of borderline ovarian tumors (BOTs) diagnosed during pregnancy.

PATIENTS AND METHODS

We conducted a retrospective multicenter study of 40 patients with BOTs diagnosed during pregnancy between 1997 and 2009 at five tertiary universitary departments of Gynecology and Obstetrics and one French cancer center. The medical records were reviewed to determine surgical procedure, histology, restaging surgery and recurrence.

RESULTS

Mean patient age was 30.2 ± 5.4 years. Most BOTs were diagnosed during the first trimester of pregnancy (62%). Salpingo-oophorectomy (N = 24) was more frequently performed than cystectomy (N = 11) during pregnancy (P = 0.01). Only two patients had an initial complete staging. BOTs were mucinous, serous and mixed in 48%, 42% and 10% of patients, respectively. Twenty-one percent of mucinous BOTs exhibited intraepithelial carcinoma or microinvasion. Forty-seven percent of serous BOTs exhibited micropapillary features, noninvasive implants or microinvasion. Restaging surgery performed in 52% patients resulted in upstaging in 24% of cases. Recurrence rate in patients with serous BOT with micropapillary features or peritoneal implants was 7.5%.

CONCLUSIONS

BOTs diagnosed during pregnancy exhibit a high incidence of aggressive features and are rarely completely staged initially. Given this setting, up-front salpingo-oophorectomy should be considered and restaging planned.

The serum CA-125 concentration data assists in evaluating CT imaging information when used to differentiate borderline ovarian tumor from malignant epithelial ovarian tumors

OBJECTIVE

We wanted to evaluate the diagnostic value of serum CA-125 concentration, when used in combination with the preoperative contrast-enhanced CT results, to differentiate borderline ovarian tumors (BOTs) from stage I malignant epithelial ovarian tumors (MEOTs).

MATERIALS AND METHODS

Ninety-eight masses (46 BOTs and 52 stage I MEOTs) from 87 consecutive patients (49 with BOTs and 38 with stage I MEOTs) who had undergone preoperative contrast-enhanced computed tomography (CT) and surgical staging were evaluated retrospectively and independently by two radiologists. The preoperative serum CA-125 concentration was measured in all patients. The utility of analyzing serum CA-125 concentration in combination with the CT results was evaluated by receiver operating characteristic (ROC) curve analysis.

RESULTS

An irregular tumor surface and lymphadenopathy were predictive of a MEOT. ROC analysis showed that the combination of CT data and the serum CA-125 level resulted in a higher diagnostic performance than did using the CT alone for differentiating BOTs from MEOTs. The areas under the curves (AUCs) without and with the use of the serum CA-125 level data were 0.67 (95% confidence interval [CI]: 0.57-0.77) and 0.78 (95% CI: 0.68-0.85), respectively, for reader 1 (p = 0.029) and 0.71 (95% CI: 0.61-0.80) and 0.81 (95% CI: 0.72-0.89), respectively, for reader 2 (p = 0.009).

CONCLUSION

The serum CA-125 concentration is of additional diagnostic value when used in conjunction with the CT imaging results for differentiating BOTs from MEOTs.

Benign and Low Grade Serous Epithelial Tumors: Recent Developments and Diagnostic Problems

This review focuses on recent advances in the area of low-grade ovarian serous neoplasia with emphasis on key diagnostic criteria, differential diagnosis, and disease classification based on current understanding of low-grade serous carcinogenesis. Despite considerable controversy surrounding serous tumors of low malignant potential (S-LMP) or borderline tumors, there have been great strides in our understanding of the serous group of borderline and malignant pelvic epithelial neoplasms in the past decade. Most S-LMP have a favorable prognosis, but recurrences and progression to carcinoma occur, sometimes following a protracted clinical course. Pathologic risk factors vary, but the extraovarian implant status is the most important predictor for progressive disease. Progression of S-LMP usually takes the form of low-grade serous carcinoma, although transformation to high-grade carcinoma is occasionally seen. A pelvic S-LMP - low-grade serous carcinoma pathway has been proposed based on global gene expression profiling, shared mutations in KRAS and/or BRAF, and in most cases, the presence of S-LMP in de novo low-grade serous carcinoma. Unlike high-grade serous carcinoma, low-grade serous carcinoma responds poorly to standard platinum-based chemotherapy. Development of more tailored therapy for S-LMP with invasive implants and low-grade serous carcinoma, ideally based on a relative risk model for disease progression, is under active clinical investigation.

Systematic evaluation of the intraoperative tumor pattern in patients with borderline tumor of the ovary

OBJECTIVE

Borderline ovarian tumors (BOTs) are rare entities with excellent prognosis depending on tumor stage and presence of invasive implants. There are limited data regarding the intraoperative tumor pattern, the actual base of optimal treatment planning. We conducted a systematic evaluation of the macroscopic and microscopic tumor spreads in patients with BOTs with special focus on the diagnosis of invasive and noninvasive lesions.

METHODS

Between January 2001 and July 2008, data of patients with BOTs were evaluated using a systematic and validated documentation tool (intraoperative mapping of ovarian cancer). Surgical outcome and pathological findings were analyzed.

RESULTS

Fifty-one patients underwent surgery for BOT. Mean (SD) age was 47.76 (15.9) years. In 6 patients (11.8%), surgery was performed for recurrence. Complete tumor resection was achieved in 47 patients (92.15%), whereas mean (SD) operative time was 126.34 (73.4) minutes. Pathologic evaluation identified 12 patients (23.53%) with mucinous and 39 patients (76.47%) with serous histologic diagnoses. Twenty-nine (56.86%) and 22 patients (43.13%) were found to have unilateral and bilateral ovarian involvements, respectively. Sixteen patients (31.37%) presented extraovarian involvement into the peritoneum (23.5%), omentum (17.7%), uterus (7.84%), sigmoid (7.8%), lymph nodes (7.8%), ileum (3.9%), mesentery (5.9%), and appendix (1.96%). Twenty patients (39.2%) had implants; of those, 9 (17.64%) and 11 patients (21.6%) have invasive and noninvasive lesions, respectively. Eight of the 9 patients with positive peritoneal cytology were associated with the presence of peritoneal implants; 3 of them with invasive character.

CONCLUSIONS

Borderline ovarian tumors require a systematic surgical evaluation to verify or exclude extrapelvic tumor lesions and allow further clinical relevant differentiation between invasive and noninvasive implants.

Low malignant potential tumors with micropapillary features are molecularly similar to low-grade serous carcinoma of the ovary

OBJECTIVE

Low-grade serous carcinoma (LGSC) is a chemoresistant ovarian neoplasm thought to potentially arise in a background of low malignant potential tumors (LMP), which are typically non-aggressive. However, LMP with micropapillary features (LMP-MP) have more aggressive clinical behavior and may represent an intermediate in progression to LGSC. The objective of this study was to obtain and compare gene expression profiles of LMP, LMP-MP and LGSC to determine if LMP-MP more closely resembles LGSC, and to identify genes involved in LGSC carcinogenesis.

METHODS

Epithelial cells from LMP (n=17), LMP-MP (n=9) and LGSC (n=11) were isolated by laser capture microdissection. RNA was extracted, reverse transcribed to cDNA, amplified and hybridized to Affymetrix U133 Plus2 genechip arrays. Gene expression data were checked for quality, filtered and significantly altered genes between subgroups were identified. Differential expression of selected genes was verified by RT-qPCR and immunohistochemistry.

RESULTS

Gene expression analysis identified differential expression between LMP and LMP-MP, LMP and LGSC but not LMP-MP and LGSC. Integration of differentially expressed genes into the protein interaction database CytoScape highlighted gene products in the MAPK pathway as differentially regulated between LMP and LGSC. Four genes were selected and validated by RT-qPCR performed on microarray samples (n=15) and immunohistochemistry on a representative microarray (n=57).

CONCLUSION

The gene expression profile of LMP-MP is similar to LGSC and distinct from LMP, reflecting their more aggressive clinical behavior. Candidate genes in the MAPK pathway were highlighted which may play a role in LGSC carcinogenesis and indicate potential therapeutic targets.

Protease inhibitor SERPINA1 expression in epithelial ovarian cancer

Epithelial ovarian cancer is the most lethal gynecologic cancer with a 5 years survival rate of 30-40% in patients diagnosed with high-grade invasive disease (TOV). This is in stark contrast to the 95% 5 years survival rate in ovarian cancer patients diagnosed with low malignant potential (LMP) disease. The progression from localized tumor to invasive metastasis involves matrix proteolysis. Protease inhibitors are thought to play a key role by limiting this process. Using the Affymetrix HG-U133A GeneChip array, we have studied all serine protease inhibitors and found several serpin family members that are differentially expressed between LMP and TOV serous tumors. SERPINA1 was selected for further study due to its high expression in the majority of LMP tumors and its low expression in TOV tumors; observations that were also validated by quantitative-PCR (Q-PCR). To study the effects of its over expression on different tumorigenic parameters, SERPINA1 was cloned in the pcDNA3.1+ plasmid which was subsequently used to derive stable clones from two invasive ovarian cancer cell lines, TOV-112D and TOV-1946. We found no effect of SERPINA1 over expression on tumor growth in SCID mice although cell migration and invasion were affected in in vitro assays. There was also no association between patient survival and SERPINA1 immunostaining, however, SERPINA1 localization was different in LMP (nuclear) and TOV (cytoplasmic) tumors. SERPINA1 remains an interesting candidate since protein homeostasis, regulated by proteases and their inhibitors, should be studied holistically in order to assess their full impact in tumor progression.

Glomeruloid peritoneal implants in ovarian serous borderline tumours--distinction between invasive and non-invasive implants and pathogenesis

AIMS

To determine whether or not the glomeruloid implants (GI) composed of papillary cores within clear spaces lined by mesothelial cells or tumour cells located in superficial or deep peritoneal tissue in ovarian serous borderline tumours (SBTs) are invasive.

METHODS AND RESULTS

We examined the differences in incidence, histological and immunohistochemical findings among three groups: 100 GI with mesothelial cells lining clear space (type I), 100 GI with tumour cells lining clear space (type II), and 100 invasive implants with clefts but no lining cells from 30 cases of SBT with peritoneal implants. The type I lesion had characteristics of non-invasive implants with a tendency for smooth contours (100/100), superficial location (71/100), absence of desmoplasia (100/100) and absence of surrounding destructive invasion (100/100), In contrast, type II GI had irregular contours (67/100), deep location (93/100), presence of desmoplastic reaction (100/100) and presence of destructive invasion (12/100). Immunohistological studies suggested intermediate forms between the two types of lesions.

CONCLUSIONS

Type I GI are non-invasive implants, whereas type II GI are invasive implants and it is important to evaluate the presence and nature of cells lining the clear space in determining whether implants associated with ovarian SBTs are invasive or not.

v-Raf Murine Sarcoma Viral Oncogene Mutation Status in Serous Borderline Ovarian Tumors and the Effect on Clinical Behavior

Aims:

To determine the incidence of activating v-raf murine sarcoma viral oncogene (BRAF) mutations in 30 serous borderline tumors (SBTs) of the ovary and the accompanying implants and to link BRAF mutation status to the clinical behavior of these tumors.

Methods and Results:

Serous borderline tumors and noninvasive implants of 30 patients were analyzed for the presence of the BRAF V599E mutation, and mutation status was correlated to 70 months of clinical follow-up. Mutation status could be assessed in 27 SBTs. Eleven (41%) showed a BRAF mulation. Four (80%) of 5 patients with bilateral SBT showed a BRAF mutation in both ovaries. From the 8 implants that were analyzed for BRAF, 2 (25%) were mutated together with their primary tumor. v-Raf murine sarcoma viral oncogene mutation positive SBTs tend to present with a lower International Federation of Gynecology and Obstetrics stage and a higher tumor volume and are less frequently aneuploid. Seventy months' follow-up indicated no significant recurrence-free survival difference between these groups.

Conclusions:

v-Raf murine sarcoma viral oncogene mutations are common in ovarian SBT, are strongly associated with bilateral tumors, and are also found in implants. A larger number of tumors should be investigated to assess clinical importance of BRAF mutation status in SBTs.

Ovarian low-grade and high-grade serous carcinoma: pathogenesis, clinicopathologic and molecular biologic features, and diagnostic problems

Ovarian serous carcinomas have been graded using various systems. Recently, a 2-tier system in which tumors are subdivided into low grade and high grade has been proposed. This approach is simplistic, reproducible, and based on biologic evidence indicating that both tumors develop via different pathways. Low-grade serous carcinomas exhibit low-grade nuclei with infrequent mitotic figures. They evolve from adenofibromas or borderline tumors, have frequent mutations of the KRAS, BRAF, or ERBB2 genes, and lack TP53 mutations (Type I pathway). The progression to invasive carcinoma is a slow step-wise process. Low-grade tumors are indolent and have better outcome than high-grade tumors. In contrast, high-grade serous carcinomas have high-grade nuclei and numerous mitotic figures. Identification of a precursor lesion in the ovary has been elusive and therefore the origin of ovarian carcinoma has been described as de novo. More recently, studies have suggested that a proportion seem to originate from intraepithelial carcinoma in the fallopian tube. The development of these tumors is rapid (Type II pathway). Most are characterized by TP53 mutations and lack mutations of KRAS, BRAF, or ERBB2. Although both types of serous carcinomas evolve along different pathways, rare high-grade serous carcinomas seem to arise through the Type I pathway. Immunohistochemical stains for p53, p16, and Ki-67 for distinction of low-grade from high-grade tumors are of limited value but can be helpful in selected instances. This review provides an update on the pathogenesis and clinicopathologic features of these 2 types of serous carcinomas and addresses some of the diagnostic problems that are encountered in routine practice.

Ovarian carcinoma pathology and genetics: recent advances

In this review we summarize recent advances in the histopathological diagnostic criteria and molecular pathology of the main subtypes of ovarian surface epithelial carcinoma. These advances have greatly improved our understanding of the biology of ovarian carcinoma and are also relevant to patient management. With progress toward subtype-specific treatment of ovarian carcinoma, accurate, reproducible histopathological diagnosis of these subtypes by practicing pathologists is increasingly important.

Vascular cell adhesion molecule-1 is a regulator of ovarian cancer peritoneal metastasis

Ovarian cancers metastasize by attaching to and invading through the mesothelium, a single layer of mesothelial cells lining the peritoneal cavity. The presence of invasive peritoneal metastases is associated with a poor prognosis for ovarian cancer (5-year survival <25%). Vascular cell adhesion molecule-1 (VCAM-1) is a cell surface receptor that mediates leukocyte attachment and extravasation across endothelial and mesothelial monolayers at sites of inflammation. Membranous VCAM-1 expression was observed on the mesothelium of 13 of 14 women with ovarian cancer compared with 6 of 15 who were cancer-free. Using a cell culture model system of mesothelial invasion, highly tumorigenic SKOV-3 and ES-2 cells were 2.5 to 3 times more efficient in transmigration through the mesothelial monolayer compared with poorly tumorigenic OVCAR-3 cells. Blocking antibodies to, or small interfering RNA knockdown of, VCAM-1 or its ligand alpha(4)beta(1) integrin significantly decreased, but did not completely inhibit, transmigration of SKOV-3 cells through mesothelial monolayers. Furthermore, using a mouse model of ovarian cancer metastasis, treatment with VCAM-1 function-blocking antibodies decreased tumor burden and increased survival. Together, these observations implicate VCAM-1-alpha(4)beta(1) integrin interactions in the regulation of ovarian cancer cell mesothelial invasion and metastatic progression and offer the possibility of novel therapeutic targets.

Low-grade serous carcinoma of the ovary displaying a macropapillary pattern of invasion

Invasive micropapillary serous carcinoma (MPSC) also designated "low-grade serous carcinoma" (LGSC) of the ovary is characterized by small micropapillae that infiltrate underlying tissue (ovarian stroma). On occasion these tumors in addition to the micropapillae contain large macropapillae lined by bland epithelium. In rare cases, the entire tumor is composed of macropapillae. In these cases, the question of whether this is an invasive carcinoma or an unusual type of adenofibroma has been raised. The goal of this study was to describe this unusual macropapillary pattern of invasion in LGSC. Cases of LGSC containing macropapillae were retrieved from the files of the Johns Hopkins Hospital. In addition to a detailed morphologic analysis, the mutational status of KRAS and BRAF in the macropapillary, noninvasive, and invasive MPSC components was analyzed by nucleotide sequencing. There were 14 cases containing macropapillae (11 cases of LGSC, 2 cases of atypical proliferative serous tumor (APST) with microinvasion, and 1 case of APST with a focus of LGSC with macropapillae in perivaginal soft tissue). In 3 cases, extraovarian metastases contained macropapillae. Molecular analysis of the primary tumor components (macropapillary, noninvasive, and invasive MPSC and/or APST) was performed in 7 cases and of a lymph node metastasis with macropapillae in 1 case. The identical KRAS mutation was detected in all of the analyzed components of the primary ovarian tumors in 4 cases. In one of these cases, macropapillae in the lymph node metastasis contained a KRAS mutation identical to the primary tumor. The BRAF mutation identified in 1 case was identical in all components of the ovarian tumor. The identical mutations in the macropapillae and the other tumor components in each case indicate that they are clonally related. The finding of macropapillae within lymph nodes supports the interpretation that the macropapillary component is another manifestation of invasion in LGSC. The recognition of this pattern is important, especially in cases when a tumor is composed entirely of macropapillae.

Recent Developments on the Significance and Pathogenesis of Lymph Node Involvement in Ovarian Serous Tumors of Low Malignant Potential (Borderline Tumors)

In approximately 27% of patients that were surgically staged for ovarian serous borderline tumors (ovarian serous tumors of low malignant potential), regional lymph nodes, most commonly the pelvic and paraaortic groups, display morphologically similar epithelial clusters. Lymph nodes above the diaphragm may also be involved. Lymph node involvement does not adversely impact the overall survival of patients with ovarian serous borderline tumors, but there is controversy as to whether this finding is associated with a decrease in recurrence-free survival. Nodular aggregates of epithelium greater than 1 mm in maximum dimension, as compared with all other patterns of nodal involvement, have been associated with reduced recurrence-free survival. The lymph nodes may also be the site of recurrence and/or progression to carcinoma of an ovarian serous borderline tumor. Recent molecular and morphologic data suggest that although most nodal implants are indeed metastatic from their synchronous ovarian neoplasms, a small subset arise de novo from nodal endosalpingiosis. The precise mechanistic basis for how these noninvasive neoplasms achieve nodal metastases is unclear. However, because most patients with nodal metastases also have peritoneal implants, tumors that are ovary-confined and without ovarian surface involvement are rarely associated with nodal involvement, microinvasive borderline tumors frequently display lymphatic vessel involvement yet show a remarkably low frequency of nodal involvement, in conjunction with the recent finding that node-positive and node-negative tumors display no significant differences in lymphatic vessel density, suggest that the route of spread to lymph nodes in most cases is via the peritoneal and not tumoral lymphatics.

Immunohistochemical profiling of benign, low malignant potential and low grade serous epithelial ovarian tumors

Background

Serous epithelial ovarian tumors can be subdivided into benign (BOV), low malignant potential (LMP) or borderline and invasive (TOV) tumors. Although the molecular characteristics of serous BOV, LMP and low grade (LG) TOV tumors has been initiated, definitive immunohistochemical markers to distinguish between these tumor types have not been defined.

Methods

In the present study, we used a tissue array composed of 27 BOVs, 78 LMPs and 23 LG TOVs to evaluate the protein expression of a subset of selected candidates identified in our previous studies (Ape1, Set, Ran, Ccne1 and Trail) or known to be implicated in epithelial ovarian cancer disease (p21, Ccnb1, Ckd1).

Results

Statistically significant difference in protein expression was observed for Ccnb1 when BOV tumors were compared to LMP tumors (p = 0.003). When BOV were compared to LG TOV tumors, Trail was significantly expressed at a higher level in malignant tumors (p = 0.01). Expression of p21 was significantly lower in LG tumors when compared with either BOVs (p = 0.03) or LMPs (p = 0.001). We also observed that expression of p21 was higher in LMP tumors with no (p = 0.02) or non-invasive (p = 0.01) implants compared to the LMP associated with invasive implants.

Conclusion

This study represents an extensive analyse of the benign and highly differentiated ovarian disease from an immunohistochemical perspective.

Genomic analysis of epithelial ovarian cancer

Ovarian cancer is a major health problem for women in the United States. Despite evidence of considerable heterogeneity, most cases of ovarian cancer are treated in a similar fashion. The molecular basis for the clinicopathologic characteristics of these tumors remains poorly defined. Whole genome expression profiling is a genomic tool, which can identify dysregulated genes and uncover unique sub-classes of tumors. The application of this technology to ovarian cancer has provided a solid molecular basis for differences in histology and grade of ovarian tumors. Differentially expressed genes identified pathways implicated in cell proliferation, invasion, motility, chromosomal instability, and gene silencing and provided new insights into the origin and potential treatment of these cancers. The added knowledge provided by global gene expression profiling should allow for a more rational treatment of ovarian cancers. These techniques are leading to a paradigm shift from empirical treatment to an individually tailored approach. This review summarizes the new genomic data on epithelial ovarian cancers of different histology and grade and the impact it will have on our understanding and treatment of this disease.

Defining an appropriate threshold for the diagnosis of serous borderline tumor of the ovary: when is a full staging procedure unnecessary?

How much borderline change in an otherwise typical ovarian serous cystadenoma should warrant classification as a serous ovarian "borderline tumor?" We correlated estimated volume and percent borderline change with stage in 56 cases of serous ovarian neoplasms (excluding carcinomas) diagnosed as at least focal borderline change to see if we could define an appropriate threshold for the diagnosis of borderline tumor that would justify full surgical staging. Forty-three cases were completely staged, 6 had "fertility-sparing" but otherwise complete staging, and 7 cases had "limited" staging. Thirty-eight cases were stage 1a-1c, and 18 were greater than stage 1. Cases with stage 1 disease had a significantly lower mean volume of borderline change sampled of 2.0 compared with 5.6 cm in cases with greater than stage 1 disease (P = 0.0002). All high-stage cases had at least 1.0 cm or more of borderline change sampled (range, 1.0-12). Cases with stage 1 disease had a significantly lower mean estimated total percent borderline change of 34.8% compared with 77.2% in cases with greater than stage 1 disease (P < 0.0001). All high-stage cases had 20% or more total borderline change (range, 20%-100%). In addition, a grossly exophytic growth pattern component was highly predictive of high stage (P < or = 0.0001). Two cases recurred-both were advanced-stage and high-percent borderline change. There were no deaths due to disease (mean follow-up, 85 months). Our study supports a conservative 10% cutoff for classification as a "borderline tumor," and that complete surgical staging is not necessary when a serous neoplasm with an intracystic growth pattern has less than 10% or 0.5-cm borderline change.

Results of the national survey of borderline ovarian tumors in Spain

MATERIAL AND METHODS

Retrospective multi-center analysis of women diagnosed with borderline ovarian tumor and treated between January 1990 and December 1997. A national survey was conducted, in which 457 patients from 27 centers corresponding to ten of Spain's autonomous communities were analyzed.

RESULTS

Four hundred fifty-seven women with borderline ovarian tumor were analyzed. The mean age of patients was 45.5+/-16.9 years. Of these, 390 patients (85.3%) were at stage I, 8 (1.8%) were at stage II and 36 (7.9%) at stage III. A bilateral tumor was observed in 63 women (13.8%). The mean tumor size was 14.2 cm and in 88 cases (19.3%) the tumor was on the surface of the ovary. Microinvasion was observed in 25 (5.5%) cases, and 29 women (6.3%) showed a micropapillary pattern. Study of the factors related to the appearance of peritoneal implants revealed positive tumor markers (OR 15.02: 1.9-32.9) and a tumor on the ovarian surface (OR 8.0: 1.8-127) to be independent risk factors. With respect to recurrence, the presence of peritoneal implants at the time of initial surgery (OR 3.4: 1.1-10.4) and signs of microinvasion in the anatomicopathological study (OR 5.5: 1.5-17.8) were found to be independent risk factors. The overall survival rate in our series was 97% with a mean follow-up of 88.3 months. The survival rate by stage was 97% for stage I, 100% for stage II and 97% for stage III.

CONCLUSIONS

Although borderline ovarian tumors have an excellent prognosis, they are not exempt from a risk of recurrence. Characterization of patients with borderline ovarian tumor is essential in order to prevent their evolution. Likewise, the taking on board of risk factors will enable more selective treatments to be offered in each case.

Differential gene expression identifies subgroups of ovarian carcinoma

Papillary serous ovarian carcinoma, the most common type of ovarian cancer, displays different biological behavior in different patients. This heterogeneity cannot be recognized by light microscopy. In this study, gene expression in 29 papillary serous ovarian carcinoma samples (21 invasive tumors and 8 borderline tumors), and 17 nonmalignant tissue types comprising 512 samples, was determined using Affymetrix U_133 oligonucleotide microarrays (Affymetrix, Inc., Santa Clara, Calif) representing approximately 40,000 known genes and expression sequence tags (ESTs). Differences in gene expression were quantified as the fold change in gene expression between the various sets of samples. A set of genes was identified that was over-expressed in the invasive ovarian carcinoma samples compared with the normal ovary samples. Principle component analysis of the set of invasive ovarian carcinomas using this set of genes revealed the existence of 2 major subgroups among the invasive ovarian carcinomas. A series of principle component analyses of the ovarian carcinomas using different gene sets composed of genes involved in different metabolic pathways also revealed the same 2 major subgroups of the invasive ovarian carcinomas. Review of the pathology by a single pathologist in a blinded manner suggested that these 2 subgroups differed in pathologic grade. Genes differentially expressed between the 2 ovarian carcinoma subsets were identified. Examination of gene expression in each ovarian carcinoma subset compared with that in 17 different normal tissue types (512 samples) revealed genes specifically over-expressed in ovarian carcinoma compared with these normal tissues. It is concluded that gene expression patterns may be useful in helping to further classify subtypes of papillary serous ovarian carcinoma that may have clinical significance. In addition, the genes identified as over-expressed in each set of serous ovarian carcinoma compared with normal tissues may represent potential biomarkers and/or targets for therapy.

Borderline ovarian tumors: current concepts for prognostic factors and clinical management

Since their original description in 1929, our knowledge of the natural history and molecular pathology of borderline ovarian tumors (BOTs) has advanced most dramatically over the last decade. It has been estimated that at the time of abdominal exploration for a serous ovarian neoplasm, a BOT will be discovered in approximately 15% of cases. These tumors commonly affect women of reproductive age, have an excellent overall prognosis and the majority are cured with surgery. Nevertheless, a subset of patients with these tumors have an adverse clinical outcome and the molecular features of the associated tumor subtype is currently being defined. These data have caused some to place this more aggressive subtype of BOT, called micropapillary serous with invasive extraovarian implants, into the pathologic continuum with frankly invasive carcinomas. This chapter will explore advances in our understanding of the natural history, clinical and pathologic features of BOTs and will conclude with a discussion of the molecular prognostic factors that might be targets for future therapy. A special emphasis will be placed on points of agreement identified during a recent workshop on BOTs sponsored by the National Cancer Institute (NCI).

Patterns of stromal invasion in ovarian serous tumors of low malignant potential (borderline tumors): a reevaluation of the concept of stromal microinvasion

Stromal-epithelial patterns of invasion in serous tumors of the ovary have been subclassified as destructive and nondestructive. By definition, well-differentiated serous tumors featuring destructive stromal invasion are classified as low-grade serous carcinomas whereas those with either no stromal invasion or stromal microinvasion are classified as serous tumors of low malignant potential (S-LMP). The histologic features of stromal microinvasion in ovarian S-LMP have been addressed in a variety of studies, but controversy persists regarding diagnostic criteria and prognostic significance, particularly in patients with high-stage disease. In addition, a subset of otherwise typical S-LMP has patterns of invasion that are not classic destructive invasion and do not meet the current diagnostic criteria for stromal microinvasion because of either qualitative features or size restrictions. To further evaluate the full histologic spectrum of stromal-epithelial patterns of invasion in otherwise typical S-LMP, we examined a series of 60 ovarian S-LMP (34 FIGO stage I; 26 FIGO stages II, III, and IV) with stromal-epithelial alterations not meeting criteria for classic destructive invasion. This group of cases included those meeting the definition of microinvasion and a subset that would be excluded based on size measurements or unusual qualitative features, but did not exhibit significant stromal reaction. Five patterns of invasion were identified: individual eosinophilic cells and cell clusters, cribriform, simple and noncomplex branching papillae, inverted macropapillae, and micropapillae. Individual, discrete aggregates of invasive epithelium ranged from 1 to 12 mm (mean, 1.4 mm) in greatest linear dimension as measured by conventional methods. The number of discrete foci ranged from 1 to greater than 10; in 7 tumors (12%), the invasive foci were diffusely scattered throughout the stroma without discrete aggregates. These stromal-epithelial alterations were associated with disease progression and/or death due to disease in 9 of 50 (18%) patients with follow-up (mean, 92.5 mo) and were covariant with other adverse prognostic features (invasive implants, nodular lymph node aggregates, high stage, and unresectable disease). Disease progression was most strongly linked to the presence of micropapillae, but the majority of patients with adverse outcome had the more common, classic stromal-epithelial patterns associated with microinvasion (ie, individual cells, cell clusters, and simple papillae). Neither size of the largest contiguous aggregate nor extent of stromal involvement correlated with outcome. Classic microinvasion disproportionately occurred in patients presenting during pregnancy (P<0.0001), and was not associated with adverse outcome in that setting, but follow-up was limited. Based on the cumulative outcome data, the presence of stromal-epithelial patterns of invasion distinct from classic destructive invasion in otherwise typical S-LMP stratifies patients at long-term risk for disease progression, but does not warrant a diagnosis of carcinoma or a change in current management schemes. Maintaining classification as a serous tumor of low malignant potential (serous borderline tumor) with stromal invasion seems appropriate even in the presence of diffuse stromal involvement or discrete aggregates measuring greater than 3 (or 5) mm. As the stromal-epithelial alteration featuring micropapillae may represent a comparatively higher-risk lesion with a clinical course analogous to that of low-grade serous carcinoma, pathologists should identify this specific stromal-epithelial pattern in the diagnostic report until sufficient data is acquired to form more definitive conclusions regarding its prognosis.

Clinical outcome and risk factors for recurrence in borderline ovarian tumours

We investigated the long-term prognosis of borderline ovarian tumours and determined risk factors for recurrence. One hundred and twenty-one borderline ovarian tumours treated between 1994 and 2003 at the participating institutions in the Tohoku Gynecologic Cancer Unit were retrospectively investigated for clinical stage, histopathological subtype, surgical technique, postoperative chemotherapy, the presence or absence of recurrence, and prognosis. The median follow-up period was 57 months (1-126 months). One hundred and nine cases (90.6%) were at clinical stage I. The histopathological subtypes consisted of 91 cases of mucinous tumour (75.2%), 27 cases of serous tumour (22.3%), and three cases of endometrioid tumour. Conservative surgery was used in 53 cases (43.8%), radical surgery in 68 cases (56.2%), a staging laparotomy in 43 cases (35.5%), and postoperative adjuvant therapy in 30 cases (24.8%). Recurrence was found in eight cases, but no tumour-related deaths were reported. Although no significant difference in disease-free survival rate was seen between different clinical stages, the difference in disease-free survival rate between serous and non-serous (mucinous and endometrioid) types was significant (P<0.05). The 10-year disease-free survival rate was 89.1% for the radical surgery group and 57.4% for the conservative surgery group -- this difference was significant (P<0.05). In the conservative surgery group, cystectomy and serous tumour were independent risk factors for recurrence. Although recurrence was observed, the long-term prognosis of borderline ovarian tumour was favourable, without tumour-related deaths. Considering the favourable prognosis, conservative surgery can be chosen as far as the patient has a non-serous tumour and receive adnexectomy. However, in cases of serous type and/or receiving cystectomy special care should be given as relative risk rates of recurrence elevate by 2-4-folds.

Fertility-sparing surgery and outcome in fertile women with ovarian borderline tumors and epithelial invasive ovarian cancer

OBJECTIVE

The aim was to evaluate the outcome of fertility-sparing treatment in ovarian borderline tumors and early invasive ovarian cancer.

MATERIALS AND METHODS

All women diagnosed with an ovarian borderline tumor or early invasive ovarian cancer who were treated with fertility-sparing surgery at the University Hospital in Lund between 1988 and 2002 were identified and included in the study (n=23).

RESULTS

During the follow-up period of a median 92 months, range 11-185 months, no relapse was found in the patients with Stage 1a tumors, including both borderline tumors (n=12) and invasive well-differentiated (n=9) and moderately differentiated (n=1) ovarian cancers. One patient with poorly differentiated ovarian cancer Stage 1c was 13 weeks' pregnant at the time of the primary operation. Although, unilateral oophorectomy was performed she insisted on continuing the pregnancy. At 37 weeks she had a cesarean section and the ovarian cancer was disseminated. Chemotherapy was given but she died less than a year later. None of the other patients received chemotherapy. In total, 30 children were born to 15 patients. Prophylactic removal of the remaining ovary+/-hysterectomy was accepted in only in six of the women after fulfilling their desire to have more children.

CONCLUSIONS

Young women with Stage 1a epithelial ovarian cancer and borderline tumors do not have to give up their fertility in order to receive successful and safe treatment of their disease. However, several of these patients do not accept the recommendation of prophylactic oophorectomy of the contralateral ovary and hysterectomy after completion of childbearing.

Lymph node involvement in ovarian serous tumors of low malignant potential (borderline tumors): pathology, prognosis, and proposed classification

The occurrence of regional lymph node involvement (LNI) in patients with primary ovarian serous tumors of low malignant potential (S-LMP), although well described in the literature, continues to be problematic. Most studies indicate that LNI is not associated with an adverse prognosis, but there has not been a comprehensive study addressing the histologic patterns of LNI, the importance, if any, of classifying the type of LNI (ie, as either noninvasive or invasive in analogy to peritoneal implant classification), or the presence and significance of associated endosalpingiosis. To further evaluate LNI in S-LMP, 74 patients with ovarian S-LMP and a lymph node biopsy or sampling were studied. Thirty-one of 74 patients had LNI in pelvic (18; 58%), mesenteric/omental (9; 29%), paraaortic (8; 26%), or supradiaphragmatic (2; 6%) lymph nodes. The number of involved nodes ranged from 1 to 20 (mean, 11.1). Four patterns of LNI were identified: individual cells, clusters of cells, and simple, nonbranching papillae (28 of 31; 90%); intraglandular (21 of 31; 68%); cells with prominent cytoplasmic eosinophilia ("eosinophilic cell" pattern) (16 of 31; 52%); and micropapillary pattern (5 of 31; 16%). LNI was diffuse in at least one lymph node in 13 patients (42%) and formed nodular aggregates greater than 1 mm in 6 patients (19%). Nodal endosalpingiosis was present in 58% of cases with LNI compared with 35% without LNI (P=0.06). There was no significant difference in survival for patients with LNI compared with patients without LNI. However, the presence of discrete nodular aggregates of epithelium greater than 1 mm in linear dimension without intervening lymphoid tissue was associated with a statistically significant decreased disease-free survival when compared with other patterns of LNI (P=0.02). Nodular aggregates were strongly associated with desmoplastic fibrous stromal reaction (P=0.001) and micropapillary architecture (0.02). There was also a trend for decreased survival among patients with LNI without associated endosalpingiosis (56%) compared with patients with LNI associated with endosalpingiosis (85%) and those with endosalpingiosis only (93%). This study suggests that patients with ovarian S-LMP may be further substratified into risk categories by the presence of nodular aggregates of S-LMP in lymph nodes, a feature that is more common in cases with micropapillary architecture and associated stromal reaction in the intranodal tumor. This high risk pattern of LNI may have a predictive value similar to invasive peritoneal implants and deserves independent evaluation in future studies of S-LMP.

Autoimplants in Serous Borderline Tumors of the Ovary

The clinical and pathologic features of serous borderline tumors (SBTs) with autoimplants (AIs) were studied with emphasis on their relation to survival, ovarian SBT with a micropapillary pattern, and their distinction from serous adenocarcinoma. The 30 patients ranged in age from 17 to 70 years (mean, 35.8 years). Two had stage I disease, 10 had stage II disease, and 18 had stage III disease. Twenty-five patients had bilateral ovarian tumors. In 28 cases, AIs were present on the surface of the neoplasm or between exophytic surface tumor papillae; in 2 cases, AIs were between papillae within intracystic tumor. The AIs consisted of single cells or glands and clusters of cells with mild to moderate nuclear atypia within a fibroblastic stroma; the stroma dominated over the epithelium in extent within the AI. In many cases, the epithelial cells in the AI had abundant eosinophilic cytoplasm. All but 2 of the patients had coexisting noninvasive peritoneal implants; 3 of them also had invasive peritoneal implants. Six of the SBTs had a micropapillary pattern; 3 of these were stage III and 3 stage II tumors. Clinical follow-up was available for 11 patients. Eight were alive and well after 4 to 7 years (mean, 5 years); 3 of these patients had stage II disease and 5 had stage III disease. Three were dead of disease after 7 to 12 years (mean, 9 years). Two patients who died of disease had stage III disease, and 1 of them had invasive implants. The third patient had stage II disease, invasive implants, and the tumor was of the micropapillary type. Our study indicates that the majority of patients with SBT with AI have stage II or III disease and abundant exophytic tumor. SBTs with AI had a micropapillary pattern in 20% of the cases. AIs do not appear to have an adverse impact on survival when controlled for peritoneal implant type and for this reason must be distinguished from true stromal invasion in serous carcinoma, a misdiagnosis sometimes made, or seriously entertained, initially in these cases. Features that favor AI over carcinoma arising in an SBT are 1) a location between tumor papillae or on the ovarian surface 2) a predominance of stroma over epithelial cells, and 3) the "borderline" cytologic appearance of epithelial cells.

Calretinin, CD34, and alpha-smooth muscle actin in the identification of peritoneal invasive implants of serous borderline tumors of the ovary

The correct identification of invasive implants in the peritoneum in serous borderline tumors (SBTs) of the ovary is an important determinant of diagnosis, treatment, and prognosis. Although the histologic criteria to distinguish noninvasive from invasive implants have been defined, the distinction can still be difficult. We examined the presence and distribution of mesothelial cells, stromal fibrocytes, and myofibroblasts in invasive and noninvasive peritoneal implants in 100 noninvasive, 100 invasive, and 100 metastatic nests/foci from 20 cases of SBTs with peritoneal implants, 10 serous carcinomas with peritoneal metastasis, and 10 cases of endosalpingiosis by immunostaining for calretinin, CD34, and alpha-SMA. All 100 invasive nests from seven SBTs and all 100 metastatic nests from the cases of serous carcinoma showed loss of calretinin+ mesothelial cells and stromal CD34+ fibrocytes around the nests. In contrast, 72/100 noninvasive nests displayed the presence of mesothelial cells around the nests and 68 displayed preservation of surrounding stromal fibrocytes. Alpha-smooth muscle actin positive myofibroblasts were present as a stromal response in 100/100 metastatic nests, 100/100 invasive nests and 54/100 noninvasive nests. The loss of mesothelial cells and stromal fibrocytes surrounding invasive nests together with a proliferation of myofibroblasts as demonstrated by immunostaining proved to be a sensitive and specific tool to separate invasive from noninvasive implants and represents an important adjunct to morphologic diagnosis. Combined sensitivity and specificity of the three antibodies was 100 and 81%, respectively. These methods, however, may not be helpful for small biopsies of noninvasive desmoplastic implants. The distribution of these cells provides some insights into the histogenesis of invasive and noninvasive implants in SBTs.

Serous and mucinous borderline (low malignant potential) tumors of the ovary

The prognosis for stage I serous borderline ovarian tumors (SBOTs) is thought to be excellent, despite rare, late recurrences. The behavior of advanced-stage SBOTs primarily depends on the invasiveness vs noninvasiveness of associated extraovarian implants. Pelvic and abdominal lymph node involvement and foci of microinvasion do not seem to adversely affect prognosis. Serous tumors with a micropapillary and/or cribriform growth pattern seem to be more frequently bilateral and exophytic and manifest at an advanced stage with a higher incidence of invasive implants than typical SBOTs. Molecular data suggest that such tumors may represent an intermediate stage in the typical SBOT-invasive low-grade serous carcinoma progression. Limited experience with endocervical (müllerian)-type mucinous borderline tumors shows a possible relation to SBOTs in clinicopathologic features and biologic behavior Intestinal-type mucinous borderline ovarian tumors (I-MBOTs) and well-differentiated mucinous carcinomas manifest at stage I in most cases; the prognosis is excellent. Mucinous tumors associated with pseudomyxoma peritonei are almost always secondary to similar tumors of the appendix or other gastrointestinal sites and should not be diagnosed as high-stage I-MBOTs. Rare primary ovarian mucinous tumors associated with pseudomyxoma peritonei are those arising in mature cystic teratomas. Advanced-stage ovarian mucinous carcinomas typically show frank, infiltrative-type invasion; the prognosis is poor.

Ovarian serous tumors of low malignant potential (borderline tumors): outcome-based study of 276 patients with long-term (> or =5-year) follow-up

The natural history, classification, and nomenclature of ovarian serous tumors of low malignant potential (S-LMP) (serous tumors of borderline malignancy, atypical proliferating tumors) are controversial. To determine long-term outcome for patients with S-LMP and further evaluate whether S-LMP can be stratified into clinically benign and malignant groups, the clinicopathologic features of 276 patients with S-LMP and > or =5 year follow-up were studied. The histology of the ovarian primary, extraovarian implants, and recurrent tumor(s) were characterized using World Health Organization criteria and correlated with FIGO stage and clinical follow-up. After censoring nontumor deaths, overall survival and disease-free survival for the 276 patients was 95% (98% FIGO stage I; 91% FIGO II-IV) and 78% (87% FIGO stage I; 65% FIGO stage II-IV), respectively. Unresectable disease (P < 0.001) and invasive implants (P < 0.001) were associated with decreased survival. When compared with typical S-LMP, S-LMP with micropapillary features were more strongly associated with invasive implants (P < 0.008) and decreased overall survival (P = 0.004), but patient outcome with micropapillary S-LMP was not independent of implant type. Stromal microinvasion in the primary tumor was also correlated with adverse outcome, independent of stage of disease, micropapillary architecture, and implant type (P = 0.03). There was no association between outcome and lymph node status. Transformation to low-grade serous carcinoma occurred in 6.8% of patients at intervals of 7 to 288 months (58% > or = 60 months) and was strongly associated with increased tempo of disease and decreased survival (P < 0.001). S-LMP forms a heterogeneous group, morphologically and clinically distinct from benign serous tumors and serous carcinoma. The majority of S-LMP are clinically benign, but recurrences are not uncommon, and persistent disease as well as deaths occur. Progression to low-grade serous carcinoma is highly predictive of more aggressive disease. Other features associated with recurrent and/or progressive disease include FIGO stage, invasive implants, microinvasion in the primary tumor, and micropapillary architecture. These predictors tend to co-occur, and no single clinical or pathologic feature or combination of features identify all adverse outcomes. The small, but significant risk of progression over time to low-grade serous carcinoma emphasizes the need for prolonged follow-up in patients with S-LMP.