Theera Tongsong

Malignant peritoneal mesothelioma mimicking ovarian cancer: a diagnostic challenge

Malignant peritoneal mesothelioma (MPM) is a rare and aggressive cancer associated with a poor prognosis. Its presentation mimics a spectrum of conditions, making diagnosis and management particularly challenging. This case highlights the difficulties in managing MPM under the constraints of diagnostic uncertainty. A nulliparous woman in her early 20s was initially diagnosed with ovarian cancer based on CT imaging, leading to laparotomy for tumour debulking with fertility-sparing procedures. However, the postoperative diagnosis of MPM necessitated reoperation for cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC), which resulted in favourable outcomes. This case underscores several important points: (1) The limitations of imaging in distinguishing MPM from ovarian cancer, (2) The critical role of pathological diagnosis, including immunohistochemical staining, in differentiating between benign and malignant mesothelioma, (3) The utility of grading MPM risk using clinical findings, the peritoneal cancer index and pathological results to guide decisions regarding subsequent neoadjuvant chemotherapy and (4) The challenges in managing a rare and aggressive malignancy, which demonstrated a favourable response to CRS-HIPEC.

Transferability of the early-stage ovarian malignancy (EOM) score: an external validation study that includes advanced-stage and metastatic ovarian cancer

To validate the diagnostic performance of the Early-stage Ovarian Malignancy (EOM) score in an external dataset that includes advanced-stage and metastatic ovarian cancer. The data from two cross-sectional cohorts were used in the statistical analysis. The development dataset of the EOM score was collected in Phrapokklao Hospital between September 2013 and December 2017. The validation dataset was collected in Maharaj Nakorn Chiang Mai Hospital between April 2010 and March 2018. The internal and external performance of the EOM score was evaluated in terms of discrimination via area under the receiver-operating characteristic curve (AuROC) and calibration. There were 270 and 479 patients included in the development and validation datasets, respectively. The prevalence of ovarian malignancy was 20.0% (54/270) in the development set and 30.3% (145/479) in the validation set. The EOM score had excellent discriminative ability in both the development and validation sets (AuROC 88.0 (95% CI 82.6, 93.9) and 88.0 (95% CI 84.3, 91.4), respectively). The EOM score also showed good calibration in both datasets. The EOM score had consistent diagnostic performance in the external validation data. It is recommended for use as a triage tool in patient referrals instead of the RMI in settings where experienced sonographers are not available.

Comparisons of Effectiveness in Differentiating Benign from Malignant Ovarian Masses between Conventional and Modified Risk of Malignancy Index (RMI)

Objective: To compare the predictive performance in differentiating benign from malignant ovarian masses between the modified risk malignancy index (RMI) and the conventional RMI (RMI-1 and RMI-2). Methods: Women scheduled for elective surgery because of adnexal masses were recruited to undergo pelvic sonography within 24 h before surgery to assess the sonographic characteristics of the masses, focusing on loculi, solid part, ascites, bilateralness, papillary projection, and color flow mapping (CFM). Preoperative CA-125 levels were also measured. Modified RMI, RMI-1, and RMI-2 systems were used to predict malignant masses. The gold standard was pathological or intraoperative diagnosis. Results: A total of 342 ovarian masses, benign: 243 (71.1%); malignant: 99 (28.9%), meeting the inclusion criteria were analyzed. The sensitivity and the specificity of the modified RMI (87.9% and 81.9%) were significantly higher than those of RMI-1 (74.7% and 84.4%), and RMI-2 (79.8% and 81.1%, respectively). Based on ROC curves, the area under the curves were 0.930, 0.881 and 0.882 for modified RMI, RMI-1 and RMI-2, respectively. Conclusion: Modified RMI had better predictive performance than the conventional RMI in differentiating between benign and malignant ovarian masses. Modified RMI may be useful to help general gynecologists or practitioners to triage patients with an adnexal mass, especially in settings of low resources.

Early-Stage Ovarian Malignancy Score versus Risk of Malignancy Indices: Accuracy and Clinical Utility for Preoperative Diagnosis of Women with Adnexal Masses

Background and objectives: To compare the diagnostic accuracy and clinical utility of the Early-stage Ovarian Malignancy (EOM) score with the Risk of Malignancy Index (RMI) in the presurgical assessment of women presenting with adnexal masses. Materials and Methods: A secondary analysis was carried out in a retrospective cohort of women who presented with an adnexal mass and were scheduled for surgery at Phrapokklao Hospital between September 2013 and December 2017. The clinical characteristics, ultrasonographic features of the masses, and preoperative CA-125 levels were recorded. The EOM and the RMI score were calculated and compared in terms of accuracy and clinical utility. Decision curve analysis (DCA), which examined the net benefit (NB) of applying the EOM and the RMI in practice at a range of threshold probabilities, was presented. Results: In this study, data from 270 patients were analyzed. Fifty-four (20.0%) women in the sample had early-stage ovarian cancer. All four RMI versions demonstrated a lower sensitivity for the detection of patients with early-stage ovarian cancer compared to an EOM score ≥ 15. An EOM ≥ 15 resulted in a higher proportion of net true positive or NB than all versions of the RMIs from a threshold probability of 5% to 30%. Conclusions: It also showed a higher capability to reduce the number of inappropriate referrals than the RMIs at a threshold probability between 5% and 30%. The EOM score showed higher diagnostic sensitivity and has the potential to be clinically more useful than the RMIs to triage women who present with adnexal masses for referral to oncologic gynecologists. Further external validation is required to support our findings.