Immune system and tumor microenvironment in early-stage breast cancer: different mechanisms for early recurrence after mastectomy and chemotherapy on ductal and lobular types.

Background: The most common type of breast cancer is the ductal type (IDC), followed by lobular type (ILC). Surgery is the main therapy for early-stage breast cancer. Adjuvant chemotherapy might be given to those at high risk of recurrence. Recurrence is still possible after mastectomy and chemotherapy and most often occurs in the first two years. We aimed to determine the mechanisms in early local recurrence in both types. Methods: We used an observational method with a cross-sectional study design. The samples were patients with early-stage IDC and ILC, who underwent modified radical mastectomy (MRM) and got adjuvant chemotherapy with taxan and anthracycline base, and experienced recurrence in the first two years after surgery. The materials in this study were paraffin blocks from surgical specimens; we examined vimentin, α-SMA and MMP1, PDGF and CD95 by immunohistochemistry (IHC). Data analysis was done using OpenEpi 3.0.1 and EZR. We used pathway analysis with linear regression. Results: There were 25 samples with local recurrence and 25 samples without recurrence in the ductal type group. The lobular type group consisted of six subjects without recurrence and seven with recurrence. There were significant differences in the expression of vimentin (p=0.000 and 0.021, respectively), PDGF (p=0.000 and 0.002) and CD95 (p=0.000 and 0.045) in ductal and lobular cancer types, respectively. MMP1 (p=0.000) and α-SMA (p=0.000) only showed a significant difference in the ductal type. The pathway analysis showed that in the ductal type, the mechanism of recurrence was enabled by two factors: α-SMA and CD95. Meanwhile, for the lobular type, the recurrence mechanism was through the CD95 pathway. Conclusions: Local recurrence in early-stage IDC and ILC had different mechanisms.  These findings are expected to make cancer treatment in both types more focused and efficient.

Sociodemographic disparities associated with advanced stages and distant metastatic breast cancers at diagnosis in Indonesia: a cross-sectional study.

Background: The global health burden of breast cancer is increasing with 5-year survival rates being much shorter in low-income and middle-income countries. Sociodemographic and clinical disparities in early cancer detection affect long-term outcome. Methods: The authors compared social, demographic, and pathological characteristics associated with metastatic and late stages of breast cancer diagnosis using data collected from a special registry developed by Perhimpunan Bedah Onkologi Indonesia (PERABOI) in 2015. Results: Of 4959 patients recruited in this study, 995 women (20.1%) were diagnosed with metastatic breast cancer. Lower education status and living in rural areas were significantly associated with Stage IV at diagnosis [odds ratio (OR)=1.256, 95% CI=1.093-1.445, P=0.001; and OR=1.197, 95% CI=1.042-1.377, P=0.012; respectively). Main complaints other than lump (ulceration, breast pain, and discharge) and occupation as a housewife were also associated with the presentation of metastatic diseases (OR=2.598, 95% CI=2.538-3.448, P<0.001 and OR=1.264, 95% CI=1.056-1.567, P=0.030, respectively). Having lower education and living outside Java and Bali islands were associated with the diagnosis of late-stage breast cancers (OR=1.908, 95% CI=1.629-2.232, P<0.001 and OR=3.039, 95% CI=2.238-4.126, P<0.001; respectively). A higher proportion of breast cancer patients were relatively younger with bigger tumour size, positive axillary nodal involvement, and more frequent Human epidermal growth factor receptor 2 overexpression. Conclusion: The authors identified sociodemographic disparities in the metastatic and late-stage diagnosis of breast cancers among Indonesian women. The subsequent action is required to reduce disparities faced by women with lower social and educational levels for early diagnosis and better healthcare access.