Comparison of clinical behavior between mucinous ovarian carcinoma with infiltrative and expansile invasion and high-grade serous ovarian carcinoma: a retrospective analysis

Mucinous ovarian carcinoma: A survey of practice in Australia and New Zealand

BACKGROUND

Mucinous ovarian carcinoma (MOC) is a rare ovarian cancer with limited evidence to support clinical care.

AIMS

We undertook a clinician survey to better understand current practice in treating MOC in Australia and New Zealand, and to determine any features associated with variation in care. In addition, we aimed to understand future research priorities.

METHODS

A RedCap survey was distributed to clinician members of the Australia New Zealand Gynaecological Oncology Group (ANZGOG). Questions included respondent demographics, three case studies and future research priorities. Clinicians were asked questions specific to their speciality.

RESULTS

Respondents (n = 47) were commonly experienced gynae-oncology specialists, most often surgical (38%) or medical (30%) oncologists. There was good consensus for surgical approaches for stage I disease; however, variation in practice was noted for advanced or recurrent MOC. Variation was also observed for medical oncologists; in early-stage disease there was no clear consensus on whether to offer chemotherapy, or which regimen to recommend. For advanced and recurrent disease a wide range of chemotherapy options was considered, with a trend away from an ovarian-type toward gastrointestinal (GI)-type regimens in advanced MOC. This practice was reflected in future research priorities, with 'Is a GI chemotherapy regimen better than an ovarian regimen?' the most highly ranked option, followed by 'Should stage 1C patients receive chemotherapy?'

CONCLUSIONS

Although the number of respondents limited the analyses, it was clear that chemotherapy selection was a key point of divergence for medical oncologists. Future research is needed to establish well-evidenced guidelines for clinical care of MOC.

Clinical implications of histologic subtypes on survival outcomes in primary mucinous ovarian carcinoma

OBJECTIVE

In 2014, the World Health Organization introduced a new histologic classification by dividing primary mucinous ovarian carcinoma (PMOC) into two: expansile (ES) or infiltrative subtypes (IS). This study investigated the clinical implications of these histological subtypes on survival outcomes.

METHODS

Data from 131 patients with PMOC who underwent primary surgery between 2003 and 2021 were analyzed. The patients baseline characteristics, surgical and pathological information were collected. Survival outcomes were calculated, while factors affecting them were also investigated.

RESULTS

During 55.9 months of median follow-up, 27 (20.6%) patients experienced recurrence and 20 (15.3%) died. Among 131 patients, 113 patients were classified into 87 (77%) ES and 26 (23%) IS after a slide review. Advanced stage, lymph node involvement, and residual tumors after surgery were more common in the IS, showing poorer prognosis. In multivariate analyses, advanced stage and residual tumors after surgery were associated with worse survival, while the IS showed no statistical significance. In subgroup analysis for stage I disease, survival did not vary between subtypes. Nevertheless, patients in the IS group who underwent fertility-sparing surgeries demonstrated a 5-year progression-free survival (PFS) rate of 83.3%, significantly lower than patients without fertility preservation, irrespective of histologic subtypes (5-year PFS rate: 97.9%; P = 0.002 for the ES, 5-year PFS rate: 100%; P = 0.001 for the IS).

CONCLUSIONS

The IS of PMOC had poorer survival outcomes and a higher proportion of advanced-stage tumors. Although its independent prognostic significance remains uncertain, adjuvant chemotherapy should be considered for patients with fertility preservation in the IS group.

Genetic analysis for mucinous ovarian carcinoma with infiltrative and expansile invasion and mucinous borderline tumor: a retrospective analysis

BACKGROUND

Mucinous carcinoma (MC) is a histological subtype of ovarian cancer that has a worse prognosis at advanced stages than the most prevalent histological subtype, high-grade serous carcinomas. Invasive patterns have been recognized as prognostic factors for MCs. MCs with infiltrative invasion were more aggressive than those with expansile invasion. MC with an expansile pattern exhibited behavior similar to mucinous borderline tumors (MBT). However, genomic analysis of invasive patterns is insufficient. This study aimed to compare genetic information between groups with MC and infiltrative invasion (Group A) and those with MC with expansile invasion or MBT (Group B).

METHODS

Ten cases each of MC with infiltrative invasion, MC with expansile invasion, and MBT between 2005 and 2020 were identified. Deoxyribonucleic acid (DNA) extraction from formalin-fixed paraffin-embedded tissues was performed, and cases with DNA fragmentation or the possibility of DNA fragmentation were excluded. Mutant base candidates and tumor mutation burden (TMB) values (mutations/megabase) were calculated.

RESULTS

After assessing the quality of purified DNA, seven cases of MC with infiltrative invasion, five cases of MC with expansile invasion, and three cases of MBT were included. More patients in group A experienced recurrence or progression (p < 0.01) and died of disease (p = 0.03). Moreover, the TMB value was statistically higher in group A than in group B (p = 0.049). There were no statistical differences in the incidence of the mutations of KRAS, TP53, and CREBBP. KRAS, TP53, and CREBBP mutations were discovered in 8/15 (53.3%), 6/15 (40.0%), and 5/15 (33.3%) cases, respectively.

CONCLUSIONS

Genetic analysis revealed that Group A had higher TMB than Group B. Therefore, this result might be useful for future treatment.