Prevalence of extracapsular extension in metastatic sentinel lymph nodes in breast cancer

Comparison of Invasive Ductolobular Carcinoma and Lobular Carcinoma: An Observational Study

Background and Objectives: Mixed ductolobular carcinomas (mDLCs) are tumors that contain both ductal and lobular components. The clinicopathological characteristics and impacts on survival of the two components, which have distinct biological behaviors, are still not clearly understood. This study aimed to compare the clinicopathological characteristics, recurrence/metastasis patterns, and survival outcomes of mDLC and invasive lobular carcinoma (ILC), as well as to investigate the prognostic significance of both histopathologies. Materials and Methods: The outcomes of 132 patients who were followed and treated between 2010 and 2021 were analyzed. Patients were examined in two groups, ILC and mDLC. Chi-square tests were performed to compare the baseline clinicopathological characteristics and treatments. Survival rates were subsequently analyzed using the Kaplan-Meier method and compared using the Cox proportional hazards model. Results: In this study, 80 (61%) patients had ILC histopathology, while 52 (39%) had mDLC histopathology. Differences between the groups were observed in median age (p = 0.038), N stage (p = 0.046), estrogen receptor (ER) status (p = 0.005), lymphovascular invasion (p = 0.007), median tumor diameter (p = 0.050), and frequency of distant metastasis (p = 0.029). The treatments, relapse patterns, and metastasis patterns were similar (p > 0.05). No differences in overall survival (OS) and disease-free survival (DFS) were observed. In the multivariate analysis, mDLC histopathology was identified as a poor prognostic factor (HR: 2.95, CI 95%: 1.10-7.88, p = 0.030). Histopathology (ILC vs. mDCL) was not identified as a prognostic factor in the Cox regression analysis for DFS. Conclusion: Although mDLC has poor clinicopathological features (younger age, more advanced N stage, more ER negativity, more lymphovascular invasion, and more frequency of metastases) and appears more aggressive than ILC, these changes do not affect survival in this study. However, mDLC histopathology seems to be associated with poor prognosis for OS.

Endometrial cancer with positive sentinel lymph nodes: pathologic characteristics of metastases as predictors of extent of lymphatic dissemination and prognosis

OBJECTIVES

To assess predictors of extensive lymph node dissemination and non-vaginal recurrence in patients with endometrial cancer with positive sentinel lymph nodes (SLNs).

METHODS

Patients with endometrial cancer who underwent primary surgery with SLN mapping and had at least one positive node between October 2013 and May 2019 were included. Positive SLNs were reviewed, and cases were classified according to the location of the metastasis (extracapsular vs intracapsular), and the size of the largest SLN metastasis (isolated tumor cells, micrometastasis, macrometastasis). Associations were assessed based on fitting logistic regression models and Cox proportional hazards models.

RESULTS

A total of 103 patients met the inclusion criteria: including 36 (34.9%) with isolated tumor cells, 27 (26.2%) with micrometastasis, and 40 (38.8%) with macrometastasis. Notably, 71.4% of patients exhibiting extracapsular SLN metastases had multiple positive SLNs (p=0.008). Extracapsular invasion (adjusted odds ratio (aOR) 5.81, 95% CI 1.4 to 23.6) and age (aOR=1.8, 95% CI 1.1 to 3.0) emerged as independent predictors of multiple positive SLNs. Among the 38 patients who underwent a backup pelvic lymphadenectomy, 18 (47.4%) presented with positive pelvic non-SLNs, a phenomenon more prevalent in patients with macrometastasis (p=0.004).Independent predictors of non-vaginal recurrence included SLN macrometastasis (adjusted hazard ratio (aHR) 3.3, 95% CI 1.3 to 8.3), non-endometrioid histology (aHR=3.7, 95% CI 1.5 to 9.3), and cervical stromal invasion (aHR=5.5, 95% CI 2.0 to 14.9). Among the 34 patients with isolated tumor cells and endometrioid histology, 3 (9%) experienced a recurrence, all of whom had not received any adjuvant chemotherapy or external beam radiotherapy.

CONCLUSION

Patients with positive SLN macrometastasis are independently associated with extensive lymphatic dissemination and distant recurrences. The risk of multiple positive SLNs increases with the extracapsular location of the SLN metastasis and with age. Independent uterine pathologic predictors of non-vaginal recurrence are non-endometrioid histology and cervical stromal invasion.

Pathologic Exploration of the Axillary Soft Tissue Microenvironment and Its Impact on Axillary Management and Breast Cancer Outcomes

PURPOSE

Axillary soft tissue (AXT) involvement with tumor cells extending beyond the positive lymph node (LN+) and extracapsular extension (ECE) has been overlooked in breast pathology specimen analysis.

MATERIALS AND METHODS

We analyzed 2,162 LN+ patients, dividing them into four groups on the basis of axillary pathology: (1) LN+ only, (2) LN+ and ECE only, (3) LN+ and AXT without ECE, and (4) LN+ with both AXT and ECE. The primary end points were 10-year locoregional failure (LRF), the 10-year axillary failure, and 10-year distant metastasis rates. Multivariable Cox models, accounting for clinical factors, were fitted using the entire cohort, and subgroups analyses were conducted.

RESULTS

The median follow-up was 9.4 years. The 10-year distant metastasis incidence was 42% for LN + AXT + ECE, 23% for both LN + AXT and LN + ECE only, and 13% for LN+ only. The 10-year axillary failure rates were 4.5% for LN + AXT + ECE, 4.6% for LN + AXT, 0.8% for LN + ECE only, and 1.6% for LN+ only. The 10-year LRF rates were 14% for LN + AXT + ECE, 10% for LN + AXT, 5.7% for LN + ECE only, and 6.2% for LN+ only. Multivariable analysis revealed that AXT was significantly associated with distant metastasis (hazard ratio [HR], 1.6; P < .001), locoregional failure (HR, 2.3; P < .001), and axillary failure (HR, 3.3; P = .003). Subgroup analyses showed that regional LN radiation (RLNR) improved locoregional tumor outcomes with AXT, ECE, or both (HR, 0.5; P = .03). Delivering ≤50 Gy to the axilla in the presence of AXT/ECE increased axillary failure (HR, 3.0; P = .04). Moreover, when delivering RLNR, axillary LN dissection could be de-escalated to sentinel node biopsy even in the presence of features such as AXT or ECE without significantly increasing any failure outcome: (HR, 1.0; P = .92) for LRF, (HR, 1.1; P = .94) axillary failure, and (HR, 0.4; P = .01) distant metastasis.

CONCLUSION

Routine reporting of axillary tissue involvement, beyond LNs and ECE, is crucial in predicting breast cancer outcomes. Ruling out the presence of AXT is imperative before any form of axillary de-escalation, especially RLNR omission.