Investigator
Princess Margaret Cancer Centre
Primary cytoreductive surgery compared with neoadjuvant chemotherapy in patients with BRCA mutated advanced high grade serous ovarian cancer: 10 year survival analysis
Given the high response to platinum based chemotherapy in We conducted a retrospective cohort study of all stage III/IV Of 314 women with germline or somatic Primary cytoreductive surgery was associated with improved survival in women with stage III/IV
Comprehensive molecular assessment of mismatch repair deficiency in Lynch associated ovarian cancers using next generation sequencing panel
Abnormalities in mismatch repair have been described in ovarian cancer, but few studies have examined the causes of mismatch repair deficiency (MMRd). To address this, we completed targeted mutational and methylation sequencing on MMRd ovarian cancer cases. The objective of this study was to explore the molecular mechanism of MMRd using our targeted next generation sequencing panel. Newly diagnosed non-serous/mucinous ovarian cancers (n=215) were prospectively recruited from three cancer centers in Ontario, Canada, between 2015 and 2018. Tumors were reflexively assessed for mismatch repair protein by immunohistochemistry. Matched tumor-normal MMRd cases were analyzed on a custom next generation sequencing panel to identify germline and somatic mutations, copy number variants, rearrangements, and promoter methylation in mismatch repair and associated genes. Of 215 cases, 28 (13%) were MMRd. The MMRd cohort had a median age of 52.3 years (range 33.6-62.2), with mostly stage I (50%) and grade 1 or 2 endometrioid histotype (57%). Of the 28 cases, 22 were available for molecular analysis, and Lynch syndrome was detected in 50% of MMRd cases (11/22; seven ovarian cancer and four synchronous ovarian and endometrial cancer: seven Use of our custom next generation sequencing panel allowed for the streamlined assessment of hereditary and somatic causes of MMRd in ovarian cancers.
Molecular Classification of Endometrial Cancers Using an Integrative DNA Sequencing Panel
ABSTRACT Background and Objectives Adoption of molecular classification in endometrial cancer (EC) into clinical practice remains challenging due to complexity in coordination of multiple assays. We aimed to develop a simple molecular technique to classify ECs into four subgroups using our custom‐designed targeted sequencing panel. Methods Patients with newly diagnosed ECs were prospectively recruited from three cancer centres in Ontario, Canada. Using our panel, 181 ECs were sequenced. Variants were analysed for pathogenicity and clinicopathologic information was collected through medical records retrospectively. Results Of 181, 86 (48%) were mismatch repair deficient (MMRd), of which 62 (72%) harboured MLH1 promoter methylation and 24 (28%) had pathogenic variants in MMR genes. Of single classifiers, three (1.8%) had pathogenic POLE ( POLE mut), 15 (9%) had TP53 mutations (p53abn) and 61 (37%) had no specific molecular profile subtype (NSMP). Sixteen (9%) had more than one molecular classifying feature, with eight (4%) MMRd‐p53abn, six (3%) POLE mut‐MMRd, one (0.5%) POLE mut‐MMRd‐p53abn and one (0.5%) POLE mut‐p53abn. When MMRd group was further subclassified according to mechanism of MMR loss, MLH1 promoter methylated group had worse outcomes than those with somatic MMR pathogenic variants. Conclusions Our panel can classify ECs into four subgroups through a simplified process and can be implemented reflexively in clinical practice.
Brief family history questionnaire to screen for Lynch syndrome in women with newly diagnosed non-serous, non-mucinous ovarian cancers
While ovarian cancer is the third most common Lynch syndrome-associated cancer in women, there is no established screening strategy to identify Lynch syndrome in this population. The objective of this study was to assess whether the 4-item brief Family History Questionnaire can be used as a screening tool to identify women with ovarian cancer at risk of Lynch syndrome. In this prospective cohort study, participants with newly diagnosed non-serous, non-mucinous ovarian cancer completed the brief Family History Questionnaire, extended Family History Questionnaire, and had tumors assessed with immunohistochemistry for mismatch repair proteins, Of 215 participants, 169 (79%) were evaluable with both the brief Family History Questionnaire and germline mutation status; 12 of these 169 were confirmed to have Lynch syndrome (7%). 10 of 12 patients (83%) with Lynch syndrome were correctly identified by the brief Family History Questionnaire, compared with 6 of 11 (55%) by the extended Family History Questionnaire, 11 of 13 (85%) by immunohistochemistry± The brief Family History Questionnaire alone or combined with immunohistochemistry may serve as an adequate screening strategy, especially in centers without access to universal tumor testing.
Tumor site discordance in mismatch repair deficiency in synchronous endometrial and ovarian cancers
For synchronous endometrial and ovarian cancers, most centers rely on mismatch repair testing of the endometrial cancer to identify Lynch syndrome, and neglect the ovarian tumor site completely. We examined the mismatch repair immunohistochemistry and microsatellite instability results from the endometrium and ovary to assess discordance between the tumor sites and between tests. 30 women with newly diagnosed synchronous endometrial and ovarian cancer were prospectively recruited from three cancer centers in Ontario, Canada. Both tumor sites were assessed for mismatch repair deficiency by immunohistochemistry and microsatellite instability test; discordance in results between tumor sites and discordance between test results at each site was examined. Cases with discordant results had tumors sequenced with a targeted panel in order to reconcile the findings. All women underwent mismatch repair gene germline testing. Of 30 patients, 11 (37%) were mismatch repair deficient or microsatellite instable at either tumor site, with 5 (17%) testing positive for Lynch syndrome. Mismatch repair immunohistochemistry expression was discordant between endometrial and ovarian tumor sites in 2 of 27 patients (7%) while microsatellite instability results were discordant in 2 of 25 patients (8%). Relying on immunohistochemistry or microsatellite instability alone on the endometrial tumor would have missed one and three cases of Lynch syndrome, respectively. One patient with Lynch syndrome with a There was discordance in immunohistochemistry and microsatellite instability results between tumor sites and between tests within each site. Endometrial tumor testing with mismatch repair immunohistochemistry performed well, but missed one case of Lynch syndrome. Given the high incidence of Lynch syndrome (17%), consideration may be given to germline testing in all patients with synchronous endometrial and ovarian cancers.
Maximizing cancer prevention through genetic navigation for Lynch syndrome detection in women with newly diagnosed endometrial and nonserous/nonmucinous epithelial ovarian cancer
BackgroundDespite recommendations for reflex immunohistochemistry (IHC) for mismatch repair (MMR) proteins to identify Lynch syndrome (LS), the uptake of genetic assessment by those who meet referral criteria is low. The authors implemented a comprehensive genetic navigation program to increase the uptake of genetic testing for LS in patients with endometrial cancer (EC) or nonserous/nonmucinous ovarian cancer (OC).MethodsParticipants with newly diagnosed EC or OC were prospectively recruited from 3 cancer centers in Ontario, Canada. Family history questionnaires were used to assess LS‐specific family history. Reflex IHC for MMR proteins was performed with the inclusion of clinical directives in pathology reports. A trained genetic navigator initiated a genetic referral on behalf of the treating physician and facilitated genetic referrals to the closest genetics center.ResultsA total of 841 participants (642 with EC, 172 with OC, and 27 with synchronous EC/OC) consented to the study; 194 (23%) were MMR‐deficient by IHC. Overall, 170 women (20%) were eligible for a genetic assessment for LS: 35 on the basis of their family history alone, 24 on the basis of their family history and IHC, 82 on the basis of IHC alone, and 29 on the basis of clinical discretion. After adjustments for participants who died (n = 6), 149 of 164 patients (91%) completed a genetic assessment, and 111 were offered and completed genetic testing. Thirty‐four women (4.0% of the total cohort and 30.6% of those with genetic testing) were diagnosed with LS: 5 with mutL homolog 1 (MLH1), 9 with mutS homolog 2 (MSH2), 15 with mutS homolog 6 (MSH6), and 5 with PMS2.ConclusionsThe introduction of a navigated genetic program resulted in a high rate of genetic assessment (>90%) in patients with gynecologic cancer at risk for LS.
Mismatch repair deficiency and prognostic significance in patients with low-risk endometrioid endometrial cancers
Mismatch repair deficiency is observed in 25%-30% of all endometrial cancers. This can be detected by the absence of mismatch repair protein staining on immunohistochemistry, and is used as a screen for Lynch syndrome. Only 10% of women with mismatch repair deficiency have Lynch syndrome, but mismatch repair deficiency may still have prognostic significance. The objective of this study was to compare clinical outcomes between mismatch repair-deficient and mismatch repair-proficient low-risk endometrioid endometrial cancers (stage IA, grade 1 or 2). This was a retrospective population-based cohort study of all low-risk endometrioid endometrial cancers (stage IA, grade 1 or 2) from the Vancouver Coastal Health Authority region from February 2011 to January 2016 that were assessed for mismatch repair deficiency. Any other histology, stage, or grade was excluded from the study. Primary outcome measures were progression-free survival and overall survival calculated using Kaplan-Meier method and log-rank tests. Cox proportional hazards model estimated the association between mismatch repair deficiency and recurrence and death after adjustment for covariates, expressed as hazard ratios (HRs). Secondary outcome measures were recurrence rates expressed per 100 person-years (p100py). There were 475 patients diagnosed with low-risk endometrioid endometrial cancer, including 131 with mismatch repair-deficient (27.6%) and 344 with mismatch repair-proficient (72.4%) tumors. Women with mismatch repair-deficient tumors had worse progression-free survival (24 months; p=0.0082) and higher recurrence rates (3.56 p100py) compared with those with mismatch repair-proficient tumors (27 months; 1.21 p100py, p=0.04). The absolute number of recurrences was overall low. There were 11 recurrences out of 131 mismatch repair-deficient cases (8.4%) and 14 out of 344 mismatch repair proficient cases (4.1%). After adjustment for age, lymphovascular space invasion status, adjuvant therapy, and post-operative grade, mismatch repair-deficient status remained associated with a higher risk of recurrence (HR 3.56, 95% CI 2.01 to 5.95). There was no significant difference in overall survival between mismatch repair groups (mismatch repair-proficient group 27.5 months vs 25.0 months in the deficient group) (HR 1.23, 95% CI 0.49 to 3.10). In low-risk stage IA grade 1 or 2 endometrioid endometrial cancers, mismatch repair deficiency is associated with a higher recurrence rate than mismatch repair proficiency after adjustment for covariates, implying that mismatch repair deficiency reflects a different biology in endometrial cancer.
Impact of lymphadenectomy and intra-operative tumor rupture on survival in early-stage mucinous ovarian cancers
Mucinous ovarian carcinoma is a rare subtype of epithelial ovarian cancer with scarce literature guiding its management. We aimed to investigate the optimal surgical management of clinical stage I mucinous ovarian carcinoma by examining the prognostic significance of lymphadenectomy and intra-operative rupture on patient survival. We conducted a retrospective cohort study of all pathology-reviewed invasive mucinous ovarian carcinomas diagnosed between 1999 and 2019 at two tertiary care cancer centers. Baseline demographics, surgical management details, and outcomes were collected. Five-year overall survival, recurrence-free survival, and the association of lymphadenectomy and intra-operative rupture on survival were examined. Of 170 women with mucinous ovarian carcinoma, 149 (88%) had clinical stage I disease. Forty-eight (32%; n=149) patients had a pelvic and/or para-aortic lymphadenectomy, but only 1 patient with grade 2 disease was upstaged due to positive pelvic lymph nodes. Intra-operative tumor rupture was documented in 52 cases (35%). On multivariable analysis, after adjusting for age, final stage, and use of adjuvant chemotherapy, there was no significant association between intra-operative rupture with overall survival (HR 2.2 (0.6-8.0); p=0.3) or recurrence-free survival (HR 1.3 (0.5-3.3); p=0.6), or lymphadenectomy with overall survival (HR 0.9 (0.3-2.8); p=0.9) or recurrence-free survival (HR 1.2 (0.5-3.0); p=0.7). Advanced stage was the only factor that was significantly associated with survival. In clinical stage I mucinous ovarian carcinoma, systematic lymphadenectomy has low utility, as very few patients are upstaged and recurrence typically occurs in the peritoneum. Furthermore, intra-operative rupture does not appear to independently confer a worse survival, and therefore these women may not benefit from adjuvant treatment based on rupture alone.
The impacts of neoadjuvant chemotherapy and of cytoreductive surgery on 10‐year survival from advanced ovarian cancer
AbstractObjectiveTo compare the long‐term survival outcomes for women with advanced ovarian cancer treated with chemotherapy either before or after surgery (neoadjuvant chemotherapy vs primary cytoreductive surgery) at a single tertiary cancer center.MethodsRetrospective cohort study of 326 patients with Stage IIIC or IV high‐grade serous ovarian cancer who received neoadjuvant chemotherapy or primary cytoreductive surgery between 2001 and 2011. Clinical treatments were recorded and 10‐year survival rates were measured.ResultsA total of 183 women (56.1%) underwent primary cytoreductive surgery and 143 women (43.9%) received neoadjuvant chemotherapy. Women who received neoadjuvant chemotherapy were more likely to have no residual disease than those who underwent primary cytoreductive surgery (51.4% vs 41.5%; P = 0.030) but experienced inferior 10‐year overall survival (9.1% vs 19.3%; P < 0.001). Among those who had primary cytoreductive surgery, those with no residual disease had superior 10‐year overall survival than those who had any evidence of residual disease (36.0% vs 7.2%; P < 0.001).ConclusionAmong women with advanced ovarian cancer, those who underwent primary cytoreductive surgery had better survival than those who received neoadjuvant chemotherapy. Neoadjuvant chemotherapy should be reserved for those in whom optimal primary cytoreductive surgery is not feasible.
Performance characteristics of screening strategies to identify Lynch syndrome in women with ovarian cancer
BackgroundFor women with ovarian cancer (OC), the optimal screening strategy to identify Lynch syndrome (LS) has not been determined. In the current study, the authors compared the performance characteristics of various strategies combining mismatch repair (MMR) immunohistochemistry (IHC), microsatellite instability testing (MSI), and family history for the detection of LS.MethodsWomen with nonserous and/or nonmucinous ovarian cancer were recruited prospectively from 3 cancer centers in Ontario, Canada. All underwent germline testing for LS and completed a family history assessment. Tumors were assessed using MMR IHC and MSI. The sensitivity, specificity, and positive and negative predictive values of screening strategies were compared with the gold standard of a germline result.ResultsOf 215 women, germline data were available for 189 (88%); 13 women (7%) had pathogenic germline variants with 7 women with mutS homolog 6 (MSH6); 3 women with mutL homolog 1 (MLH1); 2 women with PMS1 homolog 2, mismatch repair system component (PMS2); and 1 woman with mutS homolog 2 (MSH2). A total of 28 women had MMR‐deficient tumors (13%); of these, 11 had pathogenic variants (39%). Sequential IHC (with MLH1 promoter methylation analysis on MLH1‐deficient tumors) followed by MSI for nonmethylated and/or MMR‐intact patients was the most sensitive (92.3%; 95% confidence interval, 64%‐99.8%) and specific (97.7%; 95% confidence interval, 94.2%‐99.4%) approach, missing 1 case of LS. IHC with MLH1 promoter methylation analysis missed 2 patients of LS. Family history was found to have the lowest sensitivity at 55%.ConclusionsSequential IHC (with MLH1 promoter methylation analysis) followed by MSI was found to be most sensitive. However, IHC with MLH1 promoter methylation analysis also performed well and is likely more cost‐effective and efficient in the clinical setting. The pretest probability of LS is high in patients with MMR deficiency and warrants universal screening for LS.
The impact of interval between primary cytoreductive surgery with bowel resection and initiation of adjuvant chemotherapy on survival of women with advanced ovarian cancer: a multicenter cohort study
Our aim was to determine if the time interval between bowel resection and initiation of adjuvant chemotherapy impacts survival in advanced ovarian cancers. This was a retrospective cohort study using data from two cancer centers, Princess Margaret Cancer Centre in Toronto, Ontario, Canada and Samsung Comprehensive Cancer Center in Seoul, South Korea. Patients with International Federation of Gynecology and Obstetrics (FIGO) stage III or IV ovarian cancer that underwent large bowel resection during primary cytoreductive surgery (PCS) were included. Ninety-one women were eligible of which the majority (90.1%) were diagnosed with high-grade serous cancer. The median interval from PCS to chemotherapy for all patients was 21 days (7-86 days). Patients were stratified into 3 groups: 1) Interval ≤14 days, 32 (35.2%) patients; 2) Interval between 15-28 days, 27 (29.6%) patients; and 3) Interval between 29-90 days, 32 (35.2%) patients. Surgical procedures and postoperative outcomes were similar between groups. Multivariate analysis indicated that PCS to chemotherapy interval of 2-4 weeks, younger age, and completion of 4 or more adjuvant chemotherapy cycles were independent prognostic factors of favorable overall survival. Initiation of adjuvant chemotherapy between 2 to 4 weeks after PCS with bowel resection may improve survival outcomes in women with advanced ovarian cancer by maximizing the benefit of PCS plus adjuvant chemotherapy.
Survival after minimally invasive surgery in early cervical cancer: is the intra-uterine manipulator to blame?
Minimally invasive radical hysterectomy is associated with decreased survival in patients with early cervical cancer. The objective of this study was to determine whether the use of an intra-uterine manipulator at the time of laparoscopic or robotic radical hysterectomy is associated with inferior oncologic outcomes. A retrospective cohort study was carried out of all patients with cervical cancer (squamous cell carcinoma, adenocarcinoma or adenosquamous carcinoma) International Federation of Gynecology and Obstetrics 2009 stages IA1 (with positive lymphovascular space invasion) to IIA who underwent minimally invasive radical hysterectomy at two academic centers between January 2007 and December 2017. Treatment, tumor characteristics, and survival data were retrieved from hospital records. A total of 224 patients were identified at the two centers; 115 had surgery with the use of an intra-uterine manipulator while 109 did not; 53 were robotic and 171 were laparoscopic. Median age was 44 years (range 38-54) and median body mass index was 25.8 kg/m After controlling for adverse pathological factors, the use of an intra-uterine manipulator in patients with early cervical cancer who underwent minimally invasive radical hysterectomy was not an independent factor associated with rate of recurrence.
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