Nomograms for predicting overall survival and cancer-specific survival in patients with invasive micropapillary carcinoma: Based on the SEER database

Long-term outcome of invasive pure micropapillary breast cancer compared with invasive mixed micropapillary and invasive ductal breast cancer: a matched retrospective study

PURPOSE

Data on the prognostic impact of the micropapillary component in breast cancer are limited. The purpose of this study was to investigate the clinicopathological characteristics and long-term outcomes of pure and mixed invasive micropapillary breast cancer (IMPC) patients compared to invasive ductal cancer (IDC) patients.

METHODS

This retrospective study analysed all IMPC and IDC patients treated at the European Institute of Oncology (IEO) between 1997 and 2019. The overall cohort of IMPC patients was divided in two groups, pure and mixed IMPC. Each patient with mixed or pure IMPC was matched with one patient with IDC, based on year of surgery, age, pT, pN, and molecular subtype.

RESULTS

A total of 30,115 IDC, 120 pure IMPC and 150 mixed IMPC patients were considered eligible. Compared to IDC, pure and mixed IMPC patients presented a higher rate of locally advanced disease (pT2-T3, pN2-N3), vascular invasion, and Luminal B subtype. After matching, pure and mixed IMPC showed a significant higher rate of vascular invasion compared to IDC patients (p < 0.001). Invasive disease-free survival was better in IDC compared to pure IMPC patients (p = 0.11). Long-term overall survival was significantly worse in pure IMPC group compared to IDC group (p = 0.004), being instead similar between mixed IMPC vs matched IDC (p = 0.07).

CONCLUSION

These real-world data reported the worse prognosis of pure IMPC compared to IDC, highlighting the peculiar prognostic value of the micropapillary subtype itself in the decision-making process of IMPC management. An accurate pre-surgical diagnostic evaluation and a multidisciplinary approach are pivotal to best personalize its treatment.

Association of molecular subtypes and treatment with survival in invasive micropapillary breast cancer: an analysis of the Surveillance, Epidemiology, and End Results database

BACKGROUND

This study aims to examine the features, treatments, and survival of invasive micropapillary carcinoma (IMPC) according to different molecular subtypes.

METHODS

In this cohort study, data between 2010 and 2018 were retrospectively reviewed from the Surveillance, Epidemiology, and End Results database. Molecular subtypes were categorized into four varieties: hormone receptor (HR)+/HER2- (Luminal A), HR+/HER2+ (Luminal B), HR-/HER2- [triple-negative (TN)], and HR-/HER2+ (HER2 enriched).

RESULTS

In this study, 1,180 IMPC patients were included, with 99 patients (8.39%) of the 1,180 patients having an overall mortality, and 53 patients (53.54%) of the 99 patients having a breast cancer-specific mortality. The follow-up duration was 40.00 (18.50, 61.00) months. TN molecular subtype was associated with worse OS and BCSS in IMPC patients. Treatment of chemotherapy, radiation, and combination therapy were associated with better survival in HR+/HER2+ molecular subtype and HR+/HER2- molecular subtype. However, in HR-/HER2- molecular subtype, treatment of chemotherapy was associated with a poor BCSS, and treatment of radiation was not associated with OS and BCSS. Surgery treatment was not associated with survival in HR+/HER2+ molecular subtype and HR+/HER2- molecular subtype. However, surgery treatment of mastectomy was associated with better OS in HR-/HER2- molecular subtype (P < 0.05).

CONCLUSION

The prognosis of IMPC was significantly influenced by different molecular subtypes. Chemotherapy and radiotherapy are beneficial in HR+/HER2+ and HR+/HER2- patients. However, they should be used with caution in HR-/HER2- (TN) patients.

Is Metastatic Staging Needed for All Patients with Synchronous Bilateral Breast Cancers?

BACKGROUND

Patients with bilateral breast cancers are uncommon and are associated with a poorer prognosis. While metastatic staging guidelines in patients with unilateral cancer were established, the indication of metastatic staging in patients with bilateral breast cancers is unclear. We aimed to determine which patients with synchronous bilateral breast cancers require metastatic staging at diagnosis. This is the first such reported study, to the best of our knowledge.

METHODS

A retrospective review of newly diagnosed synchronous bilateral invasive breast cancer patients at our institution was performed. We excluded patients with malignant phyllodes or no metastatic staging. Patients' demographics and pathological and staging results were analysed to determine the group of bilateral breast cancer patients who required metastatic staging.

RESULTS

A total of 92 patients with synchronous bilateral invasive cancers were included. The mean age was 58 years old, and 64.1% had bilateral invasive ductal carcinoma. 23.9% had systemic metastasis. Nodal status was statistically significant for systemic metastasis on staging (p = 0.0081), with only three patients (3.3%) having negative nodal status and positive metastatic staging. These three patients, however, showed symptoms of distant metastasis. 92.3% of patients with negative nodes also had negative metastatic staging. Using negative nodal status as a guide avoided metastatic staging in 40.4% of all patients.

CONCLUSIONS

Negative nodal status was the most predictive factor for no systemic metastasis on staging in patients with synchronous bilateral invasive breast cancers. Hence, metastatic staging could be reserved for patients with symptoms of systemic metastasis and/or metastatic nodes. This finding could be validated in larger studies.