Yolk Sac Differentiation in Endometrial Carcinoma: Incidence and Clinicopathologic Features of Somatically Derived Yolk Sac Tumors Versus Carcinomas With Nonspecific Immunoexpression of Yolk Sac Markers

Endometrial somatically derived yolk sac tumors are characterized by yolk sac morphology with AFP, SALL-4, and/or Glypican-3 immunoexpression. Yolk sac marker expression, however, is not limited to tumors with overt yolk sac histology. Three hundred consecutive endometrial malignancies were assessed for immunomarkers of yolk sac differentiation. Of these, 9% expressed ≥1 yolk sac marker, including 29% of high-grade tumors. Only 3 (1%) met morphologic criteria for yolk sac differentiation; these were originally diagnosed as serous, high-grade NOS, and dedifferentiated carcinoma. Two were MMR-intact and comprised exclusively of yolk sac elements, while the dedifferentiated case was MMR deficient and had a background low-grade endometrioid carcinoma; this case also showed BRG1 loss. All 3 were INI1 intact. Nonspecific yolk sac marker expression was seen in 14 carcinosarcomas, 4 endometrioid, 2 serous, 1 clear cell, 1 dedifferentiated, 1 mixed serous/clear cell, and 1 mesonephric-like carcinoma. INI1 was intact in all cases; one showed BRG1 loss. Twenty were MMR-intact, and 4 were MMR deficient. All MMR-deficient cases with yolk sac marker expression, both with and without true yolk sac morphology, had no evidence of residual disease on follow-up, whereas 82% of MMR-intact cases developed recurrent/metastatic disease. In summary, endometrial somatically derived yolk sac tumors were rare but under-recognized. While AFP immunostaining was specific for this diagnosis, Glypican-3 and SALL-4 expression was seen in a variety of other high-grade carcinomas. INI1 loss was not associated with yolk sac morphology or immunomarker expression in the endometrium, and BRG1 loss was rare. All patients with MMR-deficient carcinomas with yolk sac immunoexpression +/- morphology were disease-free on follow-up, whereas the majority of MMR-intact cancers showed aggressive disease.

How far is too far? Cancer prevention and clinical trial enrollment in geographically underserved patient populations

Despite dedicated efforts to improve equitable access to cancer care in the United States, disparities in cancer outcomes persist, and geographically underserved patients remain at an increased risk of cancer with lower rates of survival. The critical evaluation of cancer prevention inequities and clinical trial access presents the opportunity to outline novel strategies to incrementally improve bookended access to gynecologic cancer care for geographically underserved patients. Cancer prevention strategies that can be addressed in the rural patient population mirror priorities in the Healthy People 2030 objectives and include increased identification of high risk individuals who may benefit from increased cancer screening and risk reduction, increasing the proportion of people who discuss interventions to prevent cancer, such as HPV vaccination, with their provider, and increasing the proportion of adults who complete evidence based cancer screening. Barriers to accrual to clinical trials for rural patients overlap significantly with the same barriers to obtaining health care in general. These barriers include: lack of facilities and specialized providers; lack of robust health infrastructure; inability to travel; and financial barriers. In this review, we will discuss current knowledge and opportunities to improve cancer prevention initiatives and clinical trial enrollment in geographically underserved populations with a focus on rurality.

Factors affecting adherence to a high-risk surveillance protocol among patients with Li-Fraumeni syndrome

BACKGROUND

High-risk surveillance for patients with Li-Fraumeni syndrome (LFS) has shown a stage shift and improved overall survival, but is demanding. Our objective was to evaluate surveillance adherence in a population of patients with LFS presenting for high-risk care.

METHODS

A retrospective analysis of surveillance adherence of adult patients with LFS at a single institution was performed. Adherence was defined by the duration from initial University of Virginia (UVA) LFS clinic visit to the time of first missed surveillance test. Two-sample t-tests and ANOVA tests were used to identify factors associated with duration of adherence.

RESULTS

A total of 42 patients were evaluated in the UVA LFS clinic between 2017 and 2021. Of these, 21 patients met inclusion criteria. At the time of review, 6 patients (29%) were up to date with high-risk surveillance recommendations. The mean duration of adherence was 17 months. Female sex was found to be associated with longer duration of adherence (mean 21 mo vs. 3.5 mo for males, p = 0.02). A personal history or active diagnosis of cancer was also associated with increased adherence (p = 0.02). However, neither age (p = 0.89), geography (p = 0.84), or known family history of LFS (p = 0.08) were associated with duration of adherence.

CONCLUSION

Female sex as well as a personal history of cancer were associated with longer duration of adherence to recommended high-risk surveillance among patients with LFS. Identification of barriers to surveillance will be essential moving forward to increase adherence and promote early detection of cancer, thereby reducing the morbidity and mortality of LFS.

Somatic Sequencing and Microsatellite Instability Results From Mismatch Repair-deficient Endometrial Carcinoma Patients Without Lynch Syndrome ("Lynch-like" tumors): Implications for Heritable Cancer Screening, Molecular Prognostication, and Immunotherapeutic Vulnerability

Immunostaining of endometrial carcinomas for mismatch repair (MMR) protein loss is standard-of-care for Lynch syndrome screening, but also identifies MMR-deficient tumors without germline pathogenic variants. While the majority show MLH1 hypermethylation (MLH1hm), somatic MMR pathogenic variants are increasingly recognized drivers of immunohistochemistry-germline discordance. Because MMR abnormalities with both germline and somatic origins have prognostic significance and impart susceptibility to immune checkpoint inhibitors, it is important to understand how frequently tumors with MMR immunohistochemical loss and normal germline testing ("Lynch-like" tumors) have underlying somatic MMR pathogenic variants. Somatic tumor sequencing±microsatellite instability (MSI) testing was performed on 18 endometrial cancers with MMR immunohistochemical loss but negative MMR germline results and negative MLH1hm where relevant. Tumor sequencing and MSI testing were successful in 94%. Where successful, 80% were MSI-high and 94% had a molecular correlate for the initial immunohistochemical interpretation. The single case without an identified somatic pathogenic variant was MSI-low and initially showed loss of MSH6 by immunohistochemistry but with extremely limited internal control staining. On review, MSH6 immunohistochemistry was reclassified as equivocal, and repeat staining revealed improved control expression with intact MSH6. Following reclassification of this case, 100% tumors with MMR deficiency by immunohistochemistry had at least 1 confirmed somatic MMR pathogenic variant, and 86% were MSI-high. These results demonstrate that when correctly interpreted immunohistochemistry is a strong surrogate for somatic MMR pathogenic variants and support its use as the frontline MMR biomarker in endometrial cancer for heritable screening, molecular prognostic classification, and immunotherapeutic biomarker testing purposes.

PD-L1 and MHC Class I Expression in High-grade Ovarian Cancers, Including Platinum-resistant Recurrences Treated With Checkpoint Inhibitor Therapy

Immune-modulating therapies targeting the programmed cell death-1/programmed cell death ligand-1 (PD-L1) immunosuppressive system have been used successfully in many solid tumor types. There is evidence that biomarkers such as PD-L1 and major histocompatibility complex (MHC) class I help identify candidates for anti-programmed cell death-1/PD-L1 checkpoint inhibition, though the evidence is limited in ovarian malignancies. PD-L1 and MHC Class I immunostaining was performed on pretreatment whole tissue sections in 30 cases of high-grade ovarian carcinoma. The PD-L1 combined positive score was calculated (a score of ≥1 is considered positive). MHC class I status was categorized as an intact or subclonal loss. In patients who received immunotherapy, drug response was assessed using RECIST criteria. PD-L1 was positive in 26 of 30 cases (87%; combined positive score: 1 to 100). Seven of 30 patients showed subclonal loss of MHC class I (23%), and this occurred in both PD-L1 negative (3/4; 75%) and PD-L1 positive (4/26; 15%) cases. Only 1 of 17 patients who received immunotherapy in the setting of a platinum-resistant recurrence responded to the addition of immunotherapy, and all 17 died of disease. In the setting of recurrent disease, patients did not respond to immunotherapy regardless of PD-L1/MHC class I status, suggesting that these immunostains may not be effective predictive biomarkers in this setting. Subclonal loss of expression of MHC class I occurs in ovarian carcinoma, including in PD-L1 positive cases, suggesting that the 2 pathways of immune evasion may not be mutually exclusive and that it may be important to interrogate MHC class I status in PD-L1 positive tumors to identify additional immune evasion mechanisms in these tumors.

Updates in gynecologic care for individuals with lynch syndrome

Lynch syndrome is an autosomal dominant hereditary cancer syndrome caused by germline pathogenic variants (PVs) in DNA mismatch repair genes (MLH1, MSH2, PMS2, MSH6) or the EPCAM gene. It is estimated to affect 1 in 300 individuals and confers a lifetime risk of cancer of 10-90%, depending on the specific variant and type of cancer. Lynch syndrome is the most common cause of inherited colorectal cancer, but for women, endometrial cancer is more likely to be the sentinel cancer. There is also evidence that certain PVs causing Lynch syndrome confer an increased risk of ovarian cancer, while the risk of ovarian cancer in others is not well defined. Given this, it is essential for the practicing gynecologist and gynecologic oncologist to remain up to date on the latest techniques in identification and diagnosis of individuals with Lynch syndrome as well as evidence-based screening and risk reduction recommendations for those impacted. Furthermore, as the landscape of gynecologic cancer treatment shifts towards treatment based on molecular classification of tumors, knowledge of targeted therapies well-suited for mismatch repair deficient Lynch tumors will be crucial. The objective of this review is to highlight recent updates in the literature regarding identification and management of individuals with Lynch syndrome as it pertains to endometrial and ovarian cancers to allow gynecologic providers the opportunity to both prevent and identify Lynch-associated cancers earlier, thereby reducing the morbidity and mortality of the syndrome.

Mesonephric-like Endometrial Carcinoma: Results From Immunohistochemical Screening of 300 Endometrial Carcinomas and Carcinosarcomas for This Often Overlooked and Potentially Aggressive Entity

Mesonephric-like endometrial carcinoma is a rare but frequently misclassified and aggressive malignancy. KRAS mutations, limited estrogen receptor (ER) expression, and TTF-1, GATA3, and luminal CD10 expression are described in these tumors, but an immunohistochemistry-based screening approach has not been studied. We assessed 300 endometrial carcinomas/carcinosarcomas to ascertain the specificity of TTF-1/GATA3/luminal CD10 expression with or without ER staining for this diagnosis. Next-generation sequencing and morphologic review were performed on screen-positive cases. In all, 3% (9/300) were TTF-1+; 2 coexpressed GATA3. No cases expressed luminal CD10 or GATA3 in isolation. Two TTF-1+/ER- cases, one of which was also GATA3+, were reclassified as mesonephric-like based on morphology and molecular results (KRAS mutations without mismatch repair deficiency, TP53 mutations, or PTEN mutations): these represented 0.7% of all cases (2/300). The reclassified cases were originally diagnosed as grade 1 and 2 endometrioid carcinoma, and the latter had pulmonary metastases and pelvic recurrences. Six TTF-1+ cases retained their original serous (3) and endometrioid (3) diagnoses; 1 was reclassified as dedifferentiated. All had negative or low ER. KRAS mutations were identified in 4 TTF-1+ non-mesonephric-like cases, including 1 serous and 1 grade 3 endometrioid with p53 abnormalities, 1 mismatch repair-deficient endometrioid with a complex molecular profile, and 1 endometrioid with mucinous differentiation. These findings suggest that TTF-1 and ER are good first-line screens for mesonephric-like carcinoma, but caution that a TTF-1+/ER- immunoprofile is not specific, even in the setting of KRAS mutations. A final diagnosis of mesonephric-like carcinoma requires integration of morphologic and immunohistochemical features, with molecular support when relevant.

MLH1/PMS2-deficient Endometrial Carcinomas in a Universally Screened Population: MLH1 Hypermethylation and Germline Mutation Status

MLH1/PMS2 loss due to epigenetic hypermethylation of the MLH1 promoter is the most common cause of mismatch repair deficiency in endometrial carcinoma, and typically provides reassurance against an associated germline mutation. To further characterize the genetic features of MLH1/PMS2-deficient endometrial cancers, the departmental database was searched for cases with dual MLH1/PMS2 loss and retained MSH2/6 expression which underwent MLH1 hypermethylation testing. Genetic testing results were obtained when available. One hundred seventeen endometrial cancers met inclusion criteria: 100 (85%) were MLH1-hypermethylated, 3 (3%) were low-level/borderline, 7 (6%) were nonmethylated, and 7 (6%) were insufficient for testing. Sixteen cases (12 MLH1-hypermethylated, 3 nonmethylated, and 1 insufficient for testing) underwent germline testing, 6 of which (37.5%) demonstrated germline variants of unknown significance (VUS) (MSH6, PMS2, POLD1, BRIP1, RAD51D, CHEK2) but no known deleterious mutations. Notably, however, the patients harboring the MSH6 and PMS2 germline VUS had clinical features concerning for Lynch syndrome. One nonmethylated, germline-normal case underwent somatic tumor testing, and demonstrated a somatic MLH1 mutation. In summary, MLH1-hypermethylation accounts for the vast majority of MLH1/PMS2-deficient cancers in a universally screened population, although MLH1 somatic and germline mutations can occur. Occasionally, patients with MLH1-hypermethlated tumors also bear germline VUS in other mismatch repair genes as well as genes implicated in other hereditary cancer syndromes, but their clinical relevance is unclear. Family and personal cancer histories must always be evaluated to determine the need for germline testing in women with loss of MLH1/PMS2, even in the setting of hypermethylation.

Para-Aortic Nodal Radiation in the Definitive Management of Node-Positive Cervical Cancer

Objectives

To investigate the safety and outcomes of elective para-aortic (PA) nodal irradiation utilizing modern treatment techniques for patients with node positive cervical cancer.

Methods

Patients with pelvic lymph node positive cervical cancer who received radiation were included. All patients received radiation therapy (RT) to either a traditional pelvic field or an extended field to electively cover the PA nodes. Factors associated with survival were identified using a Cox proportional hazards model, and toxicities between groups were compared with a chi-square test.

Results

96 patients were identified with a mean follow up of 40 months. The incidence of acute grade ≥ 2 toxicity was 31% in the elective PA nodal RT group and 15% in the pelvic field group (Chi-square p = 0.067. There was no significant difference in rates of grade ≥ 3 acute or late toxicities between the two groups (p>0.05). The KM estimated 5-year OS was not statistically different for those receiving elective PA nodal irradiation compared to a pelvic only field, 54% vs. 73% respectively (log-rank p = 0.11).

Conclusions

Elective PA nodal RT can safely be delivered utilizing modern planning techniques without a significant increase in severe (grade ≥ 3) acute or late toxicities, at the cost of a possible small increase in non-severe (grade 2) acute toxicities. In this series there was no survival benefit observed with the receipt of elective PA nodal RT, however, this benefit may have been obscured by the higher risk features of this population. While prospective randomized trials utilizing a risk adapted approach to elective PA nodal coverage are the only way to fully evaluate the benefit of elective PA nodal coverage, these trials are unlikely to be performed and instead we must rely on interpretation of results of risk adapted approaches like those used in ongoing clinical trials and retrospective data.

A Surgical Window Trial Evaluating Medroxyprogesterone Acetate with or without Entinostat in Patients with Endometrial Cancer and Validation of Biomarkers of Cellular Response

PURPOSE

This surgical window of opportunity (window) study assessed the short-term effect of medroxyprogesterone acetate (MPA) alone versus MPA plus the histone deacetylase (HDAC) inhibitor entinostat on regulation of progesterone receptor (PR) in women with newly diagnosed endometrioid endometrial adenocarcinoma.

PATIENTS AND METHODS

This multisite, randomized, open-label surgical window study treated women intramuscularly on day 1 with 400 mg MPA. Entinostat given 5 mg by mouth on days 1, 8, and 15 was randomly assigned with equal probability. Surgery followed on days 21-24. Pretreatment and posttreatment tissue was assessed for PR H-scores, Ki-67 levels, and histologic response.

RESULTS

Fifty patients were accrued in 4 months; 22 and 20 participants had PR evaluable pretreatment and posttreatment slides in the MPA and MPA/entinostat arms, respectively. Median posttreatment PR H-scores were significantly lower than pretreatment H-scores in both arms but did not differ significantly (MPA: 247 vs. 27, MPA/entinostat 260 vs. 23, respectively, P = 0.87). Decreased Ki-67 was shown in 90% treated with MPA/entinostat compared with 68% treated with MPA alone (P = 0.13). Median PR H-score decreases were larger when Ki-67 was decreased (208) versus not decreased (45). The decrease in PR pretreatment versus posttreatment was associated with loss of Ki-67 nuclear staining, consistent with reduced cellular proliferation (P < 0.008).

CONCLUSIONS

This surgical window trial rapidly accrued in a multisite setting and evaluated PR as its primary endpoint and Ki-67 as secondary endpoint. Despite no immediate effect of entinostat on PR in this short-term study, lessons learned can inform future window and treatment trials.

Evaluation of breast screening strategies in a high risk breast and ovarian cancer clinic

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BRCA mutation carriers are more likely to be diagnosed with breast cancer compared to high-risk non-BRCA carriers.

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MRI was able to effectively identify DCIS in the BRCA population.

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In BRCA mutation carriers younger than 40, there were no MRI occult cancers found.

Recent data suggest that BRCA mutation carriers younger than 40 may not benefit from mammography in addition to MRI. Our objective was to evaluate screening modalities utilized in a high-risk population. Clinicopathologic data were abstracted for patients followed in a high risk clinic from 2007 to 2017. Descriptive statistics were calculated and associations between categorical variables were evaluated using chi-square tests. 631 women comprised the study population; 496 patients had no known mutation (79%), 128 (20%) had a BRCA mutation, and 7 patients had other deleterious mutations. BRCA mutation carriers were more likely to have cancers diagnosed after mammogram callbacks (p = 0.0046) and biopsies (p = 0.0026) compared to non-BRCA mutation carriers. BRCA mutation carriers were also more likely to have cancers diagnosed after biopsies following screening MRI (p = 0.045). 13 BRCA patients were diagnosed with cancer (average age 51). Of the cancers diagnosed after abnormal MRI, 3 were DCIS; all 3 patients had a normal mammogram 4–6 months prior. In those found after abnormal mammogram (n = 6), follow up MRI was performed in 4 cases; all demonstrated the lesion. Three patients were diagnosed younger than 40, 1 on mammogram and 2 on MRI. The patient diagnosed on mammogram had no prior MRI and the lesion was seen on follow-up MRI. Interval screening MRI identified DCIS in BRCA patients with a previous normal mammogram and cancers diagnosed on mammogram were all identified on follow-up MRI. These findings support further evaluation of MRI alone until age 40 in BRCA mutation carriers.

Genetic counseling referral for ovarian cancer patients: a call to action

The hereditary contribution to ovarian cancer has been increasingly recognized over the past decade, with a 2014 Society of Gynecologic Oncology (SGO) recommendation for all women with epithelial ovarian cancer to be considered for genetic testing. The objective of the study was to determine if disparities exist in genetic referrals and characterize referral patterns over time. A retrospective cohort study included all women diagnosed with invasive epithelial ovarian cancer at the University of Virginia from 2004 to 2015. Clinicopathologic data were abstracted from the electronic medical record and analyzed for association with genetic referral and testing. We identified 696 cases, with a median age of 62 years and a median follow up of 25.2 months (range 1-115). Thirty-four percent were referred for genetic counseling with an 80% genetic testing rate in those women. Referrals increased from a rate of 8% in 2004 to 68% in 2015. On multivariable analysis, papillary serous histology (OR 1.6, 95% CI 1.0-2.6), stage III disease (OR 3.4, 95% CI 1.6-7.5), ovarian cancer family history (OR 2.6, 95% CI 1.5-4.6), breast cancer family history (OR 1.7, 95% CI 1.1-2.5), and diagnosis after 2014 (OR 2.3, 95% CI 1.3-4.1) remained significantly associated with genetics referral. Older age and living > 100 miles away were associated with decreased referral (OR 0.97, 95% CI 0.95-0.99 per year and OR 0.49, 95% CI 0.28-0.86). As only 68% of women with epithelial ovarian cancer were referred in 2015 innovative strategies such as Medicare coverage for counseling are still needed to universalize testing.

Cases and evidence for panel testing in cancer genetics: Is site-specific testing dead?

Historically in cancer genetic counseling, when a pathogenic variant is found which explains the cancers in the family, at risk family members are offered site-specific testing to identify whether or not they have the previously identified pathogenic variant. Factors such as turnaround times, cost, and insurance coverage all made site-specific testing the most appropriate testing option; however, as turnaround times and costs have substantially dropped and the recognition of double heterozygous families and families with nontraditional presentations has increased, the utility of site-specific testing should be questioned. We present four cases where ordering site-specific testing would have missed a clinically relevant pathogenic variant which raises the question of whether or not site-specific testing should be regularly used in cancer genetic testing.

Evaluation of screening and risk-reducing surgery for women followed in a high-risk breast/ovarian cancer clinic: it is all about the tubes in BRCA mutation carriers

The objectives of this study were to determine both surgical and subsequent cancer outcomes for high-risk women from the University of Virginia's High-Risk Breast/Ovarian Cancer clinic undergoing ovarian cancer risk-reducing surgery. Retrospective review identified high risk women who had ovarian risk reducing surgery over the past decade and surgical outcomes, pathology, pre-operative screening results, and pre-/post-operative cancer diagnoses were evaluated. One hundred and eighty-three high-risk women had risk reducing surgery at a mean age of 50.1 years and with a mean BMI of 28.9 kg/m2 at the time of surgery. Most women (103; 56.3%) had a strong family history of cancer concerning for a hereditary syndrome without an identified mutation, 35.5% of women carried a known deleterious mutation and 7.7% of women had a personal history of breast or ovarian cancer. The most common procedure was a risk-reducing bilateral salpingo-oophorectomy with or without hysterectomy (RRBSO, 89.1%). All women underwent the Sectioning and Extensively Examining the Fimbriated End (SEE-FIM) pathology protocol which found two (1.1%) invasive ovarian cancers (one ovarian/tubal carcinosarcoma, one granulosa cell ovarian cancer), three (1.6%) serous tubal intraepithelial carcinomas (STIC), and one (1.1%) invasive fallopian tube cancer. Subsequent cancer diagnoses included one (0.5%) primary peritoneal cancer, four (2.2%) DCIS, and seven (3.8%) invasive breast cancers. Ultimately, among all high-risk women undergoing RR surgery, about 3.3% were diagnosed with a STIC or an ovarian cancer none of which were identified on screening. All STIC and tubal cancers were diagnosed in women with BRCA mutations (6.6% rate for this group).

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Ovarian risk reducing surgery improves outcomes.

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Women with BRCA 1 mutations have a higher risk of occult tubal pathology.

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Subsequent cancers, particularly breast cancer, occur in these women.

Gene Expression Analysis Identifies Novel Targets for Cervical Cancer Therapy

Although there has been significant progress in prevention and treatment of cervical cancer, this malignancy is still a leading cause of cancer death for women. Anti-angiogenesis and immunotherapy approaches have been providing survival benefits, however, response rates and durability of response need to be improved. There is a clear need for combination therapies that increase effectiveness of these agents and further improve patient outcome. Previous studies have largely focused on gene expression and molecular pathways in untreated cervix cancer. The goal of this study was to evaluate cancer-specific molecular pathways and their correlation with tumor immune profile in recurrent cervical cancer. Tumor and adjacent normal tissues were used to identify potential combination therapy targets. We found that DNA damage repair pathway genes were significantly overexpressed in the tumor. Based on our results and other recent investigations, we suggest that combination immune checkpoint and PARP inhibitor therapy is a high priority consideration for patients with recurrent, previously treated cervical cancer. We also show that multiple epithelial-mesenchymal transition-related genes, including MAP2K4, ID2, JAK1, FGF2, PIK3R1, AKT3, FGF13, and STAT3 may be potential targets. Interestingly, high-throughput analysis of Cancer Genome Atlas data identified distinct targets, including Fatty acid synthase FASN and Matrix Metallopeptidase 1 MMP1 as novel, promising combination therapy partners.

Current and future role of genetic screening in gynecologic malignancies

The world of hereditary cancers has seen exponential growth in recent years. While hereditary breast and ovarian cancer and Lynch syndrome account for the majority of mutations encountered by gynecologists, newly identified deleterious genetic mutations continue to be unearthed with their associated risks of malignancies. However, these advances in genetic cancer predispositions then force practitioners and their patients to confront the uncertainties of these less commonly identified mutations and the fact that there is limited evidence to guide them in expected cancer risk and appropriate risk-reduction strategies. Given the speed of information, it is imperative to involve cancer genetics experts when counseling these patients. In addition, coordination of screening and care in conjunction with specialty high-risk clinics, if available, allows for patients to have centralized management for multiple cancer risks under the guidance of physicians with experience counseling these patients. The objective of this review is to present the current literature regarding genetic mutations associated with gynecologic malignancies as well to propose screening and risk-reduction options for these high-risk patients.

Endometrial Cancers With Activating KRas Mutations Have Activated Estrogen Signaling and Paradoxical Response to MEK Inhibition

OBJECTIVES

The aims of this study were to determine if activating KRas mutation alters estrogen signaling in endometrial cancer (EC) and to explore the potential therapeutic impact of these alterations.

METHODS

The Cancer Genome Atlas was queried for changes in estrogen-regulated genes in EC based on KRas mutation status. In vitro studies were conducted to evaluate estrogen receptor α (ERα) phosphorylation changes and related kinase changes in KRas mutant EC cells. The resulting effect on response to MEK inhibition, using trametinib, was evaluated. Immunohistochemistry was performed on KRas mutant and wild-type EC tumors to test estrogen signaling differences.

RESULTS

KRas mutant tumors in The Cancer Genome Atlas showed decreased progesterone receptor expression (P = 0.047). Protein analysis in KRas mutant EC cells also showed decreased expression of ERα (P < 0.001) and progesterone receptor (P = 0.001). Although total ERα is decreased in KRas mutant cells, phospho-ERα S118 was increased compared with wild type. Treatment with trametinib in KRas mutant cells increased phospho-ERα S167 and increased expression of estrogen-regulated genes. While MEK inhibition blocked estradiol-stimulated phosphorylation of ERK1/2 and p90RSK in wild-type cells, phospho-ERK1/2 and phospho-p90RSK were substantially increased in KRas mutants. KRas mutant EC tumor specimens showed similar changes, with increased phospho-ERα S118 and phospho-ERα S167 compared with wild-type EC tumors.

CONCLUSIONS

MEK inhibition in KRas mutant cells results in activation of ER signaling and prevents the abrogation of signaling through ERK1/2 and p90RSK that is achieved in KRas wild-type EC cells. Combination therapy with MEK inhibition plus antiestrogen therapy may be necessary to improve response rates in patients with KRas mutant EC.

Potential immunotherapy targets in recurrent cervical cancer

OBJECTIVE

Our objective was to characterize the intra and peritumoral immune profile in recurrent cervical cancers to identify rational immunotherapy targets.

METHODS

Archival pelvic exenteration specimens were examined using a validated multiplex immuno-fluorescent panel of antibodies against cluster of differentiation 8 (CD8), cluster of differentiation 68 (CD68), forkhead box P3 (FoxP3), programmed cell death protein 1 (PD1), and programmed death-ligand 1 (PD-L1, N=28). Clinical data were abstracted from the electronic medical record.

RESULTS

Cytotoxic T cells, macrophages, and regulatory T cells were found in higher densities in peritumoral stroma (CD8+ density 497.7 vs 83.5, p<0.0001, CD68+ density 345.0 vs 196.7, p=0.04, FoxP3+ density 214.5 vs 35.6, p<0.0001). Antigen experienced T cells (PD1+) were higher in peritumoral compared to tumor tissue (median normalized fluorescence intensity 0.05 vs 0.0085, p<0.001). Although there was a higher median density of intratumoral cytotoxic T cells and macrophages compared to regulatory T cells (median density CD8+ 83.5 vs 35.6, p<0.05, median density 196.7 vs 35.6, p<0.05), the presence of macrophages correlated with the presence of regulatory T cells in tumors (r=0.58, p=0.001).

CONCLUSIONS

While cytotoxic T cells are present in tumor tissue to varying degrees, their density is lower than in peritumoral stroma, suggesting intratumoral exclusion or destruction of T cells. Higher densities of intratumoral macrophages compared to regulatory T cells suggest macrophages may be important contributors to the immunosuppressive tumor environment. Future directions for combination therapy include altering T cell trafficking and targeting tumor associated macrophages (TAMs) to enhance intratumoral activated T cell density and effect a more robust immune response.

Clinical Challenges Associated with Universal Screening for Lynch Syndrome-Associated Endometrial Cancer

Universal testing for Lynch syndrome is now a routine component of the diagnostic work-up of endometrial cancer patients. The purpose of this study was to identify prospectively the barriers to universal screening based on a tissue testing approach [microsatellite instability (MSI) analysis, IHC for DNA mismatch repair proteins, and MLH1 methylation analysis]. Endometrial carcinoma patients (n = 213) prospectively underwent microsatellite instability and IHC testing for expression of DNA mismatch repair (MMR) proteins. Patients with low (MSI-L) or high (MSI-H) levels of tumor MSI or immunohistochemical loss of MLH1 (and absent MLH1 methylation), MSH2, MSH6, or PMS2 were referred to a genetic counselor for consideration of germline testing. Six discordances (3.1% of tested cases) between IHC and MSI were identified. Half of these exhibited heterogeneous immunohistochemical loss of MLH1/PMS2 and were microsatellite stable (MSS). Of the remaining cases, one was MSS with immunohistochemical loss of MSH6, one was MSS with immunohistochemical loss of MLH1/PMS2 and absent MLH1 promoter methylation, and one was MSI-H with intact expression of DNA MMR proteins. Four patients had MSI-L tumors with intact immunohistochemical protein expression; the clinical significance of MSI-L in endometrial cancer is unclear. Eight patients did not have germline mutations despite tissue testing suggesting Lynch syndrome. Including cases with insufficient tissue for testing and patients declining tissue or germline testing, we encountered significant barriers to universal screening in 13.6% of screened patients (29/213) that preclude designation of a tumor as sporadic or hereditary. Cancer Prev Res; 10(2); 108-15. ©2016 AACR.

Germline multi-gene hereditary cancer panel testing in an unselected endometrial cancer cohort

Hereditary endometrial carcinoma is associated with germline mutations in Lynch syndrome genes. The role of other cancer predisposition genes is unclear. We aimed to determine the prevalence of cancer predisposition gene mutations in an unselected endometrial carcinoma patient cohort. Mutations in 25 genes were identified using a next-generation sequencing-based panel applied in 381 endometrial carcinoma patients who had undergone tumor testing to screen for Lynch syndrome. Thirty-five patients (9.2%) had a deleterious mutation: 22 (5.8%) in Lynch syndrome genes (three MLH1, five MSH2, two EPCAM-MSH2, six MSH6, and six PMS2) and 13 (3.4%) in 10 non-Lynch syndrome genes (four CHEK2, one each in APC, ATM, BARD1, BRCA1, BRCA2, BRIP1, NBN, PTEN, and RAD51C). Of 21 patients with deleterious mutations in Lynch syndrome genes with tumor testing, 2 (9.5%) had tumor testing results suggestive of sporadic cancer. Of 12 patients with deleterious mutations in MSH6 and PMS2, 10 were diagnosed at age >50 and 8 did not have a family history of Lynch syndrome-associated cancers. Patients with deleterious mutations in non-Lynch syndrome genes were more likely to have serous tumor histology (23.1 vs 6.4%, P=0.02). The three patients with non-Lynch syndrome deleterious mutations and serous histology had mutations in BRCA2, BRIP1, and RAD51C. Current clinical criteria fail to identify a portion of actionable mutations in Lynch syndrome and other hereditary cancer syndromes. Performance characteristics of tumor testing are sufficiently robust to implement universal tumor testing to identify patients with Lynch syndrome. Germline multi-gene panel testing is feasible and informative, leading to the identification of additional actionable mutations.

Consequences of universal MSI/IHC in screening ENDOMETRIAL cancer patients for Lynch syndrome

OBJECTIVE

Determine factors impacting the uptake of genetic counseling and results of genetic testing following universal tumor testing for Lynch syndrome in patients with endometrial cancer.

METHODS

The study population consisted of two unselected cohorts of endometrial cancer patients, 408 identified retrospectively and 206 identified prospectively. Immunohistochemistry for mismatch repair protein expression and/or microsatellite instability analysis was performed on these tumors. MLH1 methylation analysis was performed on tumors with loss of MLH1 protein. Tumor studies were considered suggestive of Lynch Syndrome if they showed immunohistochemical loss of MSH2, MSH6 or PMS2, loss of MLH1 without MLH1 promoter methylation, and/or microsatellite instability. Participants with suggestive tumor studies were contacted and offered genetic counseling and testing.

RESULTS

In the retrospective cohort, 11% had tumor studies suggestive of Lynch syndrome, and 42% was seen for genetic counseling. A germline mutation was detected in 40%, and one had a variant of uncertain significance. In the prospective cohort, 8.7% of patients had tumor testing suggestive of Lynch syndrome; 72% were seen for genetic counseling. Germline mutations were found in 40%, and one had a variant of uncertain significance. Common challenges included timing of re-contact, age, perceived lack of relevance, inability to travel and limited insurance coverage.

CONCLUSIONS

There are several barriers to genetic counseling and testing follow-up after universal tumor testing, and uninformative genetic test results present a management challenge. It is important to consider these limitations when implementing an approach to screening endometrial cancer patients for Lynch syndrome.

Extended-field radiation therapy with whole pelvis radiotherapy and cisplatin chemosensitization in the treatment of IB2-IIIB cervical carcinoma: a retrospective review

OBJECTIVE

This retrospective study evaluated the toxicity of extended-field radiation therapy (EFRT), whole pelvis radiotherapy, and concurrent chemotherapy in patients treated with IB2-IIIB cervical carcinoma.

STUDY DESIGN

Patients treated with EFRT, whole pelvis radiotherapy, and concurrent chemotherapy were analyzed for toxicity. Median prescribed dose to the whole pelvis was 45 Gy (45-50 Gy). Median prescribed dose to the paraaortic lymph nodes was 45 Gy (36-50). Thirty-five patients received cisplatin chemosensitization at a median dose of 40 mg/m(2) (40-51), with a median of 5 cycles (2-6).

RESULTS

Thirty-six patients were treated, 3 with positive paraaortic lymph nodes. The median follow-up interval was 32 months. Twenty-four patients (66.7%) had no evidence of disease at last follow-up. Thirteen patients (36.1%) had recurrence. Fifteen patients (41.7%) experienced acute grade 3 toxicity.

CONCLUSION

Increased toxicity in patients warrants careful patient selection.