Breast carcinomas with osteoclast-like giant cells: a comprehensive clinico-pathological and molecular portrait and evidence of RANK-L expression

The "Forgotten" Subtypes of Breast Carcinoma: A Systematic Review of Selected Histological Variants Not Included or Not Recognized as Distinct Entities in the Current World Health Organization Classification of Breast Tumors

Breast carcinoma is the most common cancer in women. Nineteen different subtypes of breast carcinomas are recognized in the current WHO classification of breast tumors. Except for these subtypes, there are a number of carcinomas with special morphologic and immunohistochemical features that are not included in the 5th WHO classification, while others are considered special morphologic patterns of invasive breast carcinoma of no special type. In this manuscript, we systematically review the literature on four different subtypes of invasive breast carcinoma, namely lymphoepithelioma-like breast carcinoma, breast carcinoma with osteoclast-like giant cells, signet-ring breast carcinoma, and metaplastic breast carcinoma with melanocytic differentiation. We describe their clinicopathological characteristics, focusing on the differential diagnosis, treatment, and prognosis.

Giant cell tumor of distal radius: En bloc resection with allograft reconstruction: A case report

Key Clinical Message

Giant cell tumor of bone (GCT) is a rare neoplasm which often presents as a lytic lesion in the epiphyseal region of long bones and which are usually accompanied by pain, swelling, and restricted movement.

Abstract

Giant cell tumor of bone (GCT) is a rare neoplasm that affects individuals in their third and fourth decades of life. Clinically, it often presents as a lytic lesion in the epiphyseal region of bones, notably the distal femur and proximal tibia. Radiologically, GCT appears as a distinct lytic lesion in the epiphyseal region. Histopathologically, GCTs are composed of mononuclear cells, macrophages, and multinuclear giant cells, indicative of osteoclastogenic stromal tumors. A 37-year-old man presented with left wrist pain, swelling, and restricted movement persisting for a year, worsening over the last 7 months. Radiographic assessments revealed a distal radius bone mass involving the radiocarpal joint. Biopsy confirmed a GCT with extension into peripheral muscle. PET/CT scan showed localized pathology without metastasis. Histopathologically, GCT exhibited multinucleated giant cells, spindle cells, and aneurysmal bone cyst-like regions with coagulation necrosis. Surgical resection involved en-bloc removal and reconstruction with a non-vascularized radius bone graft. Postoperatively, the patient showed no complications at the one-year follow-up, suggesting successful intervention.

Single-cell transcriptomics provide insight into metastasis-related subsets of breast cancer

Breast cancer metastasis is a complex, multi-step process, with high cellular heterogeneity between primary and metastatic breast cancer, and more complex interactions between metastatic cancer cells and other cells in the tumor microenvironment. High-resolution single-cell transcriptome sequencing technology can visualize the heterogeneity of malignant and non-malignant cells in the tumor microenvironment in real time, especially combined with spatial transcriptome analysis, which can directly compare changes between different stages of metastatic samples. Therefore, this study takes single-cell analysis as the first perspective to deeply explore special or rare cell subpopulations related to breast cancer metastasis, systematically summarizes their functions, molecular features, and corresponding treatment strategies, which will contribute to accurately identify, understand, and target tumor metastasis-related driving events, provide a research basis for the mechanistic study of breast cancer metastasis, and provide new clues for its personalized precision treatment.

Expression of RANKL in breast cancer tissue in patients with fibrous dysplasia/McCune-Albright syndrome

BACKGROUND

In fibrous dysplasia/McCune-Albright syndrome (FD/MAS), mosaic mutations in the GNAS gene lead to locally abnormal bone turnover. Additionally, patients with FD/MAS, particularly with thoracic lesions, have an increased risk for breast cancer. Development and progression of breast cancer has been associated with expression of Receptor Activator of NF-κB ligand (RANKL) in mammary tissue, and due to the GNAS mutation, RANKL is systemically increased in patients with FD/MAS. Yet it is unknown whether breast cancer in FD/MAS is also dependent on RANKL. We hypothesized that the GNAS mutation might induce RANKL overproduction and an oncogenic niche in mammary tissue, and examined RANKL expression in breast cancer tissue of patients with FD/MAS compared to controls.

METHODS

Nine patients with FD/MAS and breast cancer were included and clinical data were retrieved. Patients were matched to controls with breast cancer without FD/MAS based on age and tumor type. Three pregnant breast cancer patients were included as positive controls. Immunohistochemical detection of RANKL was performed on formalin-fixed paraffin-embedded breast cancer specimens. Staining intensity was classified as weak, moderate or intense. The area of positive RANKL staining divided by the total ductal-lobular area was assessed (positive area percentage, PAP). Number of patients with RANKL expression was compared between FD/MAS and control group by chi-square (χ²) test, the PAP by Mann-Whitney U test (MWU).

RESULTS

RANKL expression was observed in 3 patients with FD/MAS (38 %), mainly in healthy tissue, and none of the control patients (χ²p = 0.055). The FD/MAS group demonstrated considerably more intense staining than the control group, comparable to positive controls. The median PAP was 0.64 % (range 0.14-2.04 %) in the 3 FD/MAS patients with RANKL expression, 0.01 % (Q1-Q3: 0.0003-0.514 %) in the entire FD/MAS group, 0.006 % (Q1-Q3: 0.001-0.012 %) in the control group (MWU = 0.574), and 0.19 % (0.08-0.32 %) in the pregnant patients. All patients with FD/MAS and RANKL expression had thoracic bone lesions, but no correlation was observed between RANKL expression and presence of the GNAS mutation or FD disease burden.

CONCLUSIONS

The triad of a higher number of patients, higher positive area percentage and stronger intensity in the FD/MAS compared to the control group indicates that RANKL may be upregulated in mammary tissue in a subset of patients with FD/MAS, which may explain the increased risk for breast cancer, although the clinical significance remains unclear. Further research is needed to establish risk profiles for the development of RANKL-positive breast cancer and to improve early screening and treatment.

Invasive breast carcinoma with osteoclast-like stromal giant cells: A case report

BACKGROUND

Invasive breast carcinoma with osteoclast-like stromal giant cells (OGCs) is an extremely rare morphology of breast carcinomas. To the best of our knowledge, the most recent case report describing this rare pathology was published six years ago. The mechanism controlling the development of this unique histological formation is still unknown. Further, the prognosis of patients with OGC involvement is also controversial.

CASE SUMMARY

We report the case of a 48-year-old woman, who presented to the outpatient department with a palpable, growing, painless mass in her left breast for about one year. Sonography and mammography revealed a 26.5 mm × 18.8 mm asymmetric, lobular mass with circumscribed margin and the Breast Imaging Reporting and Data System was category 4C. Sono-guided aspiration biopsy revealed invasive ductal carcinoma. The patient underwent breast conserving surgery and was diagnosed with invasive breast carcinoma with OGCs, grade II, with intermediate grade of ductal carcinoma in situ (ER: 80%, 3+, PR: 80%, 3+, HER-2: negative, Ki 67: 30%). Adjuvant chemotherapy and post-operation radiotherapy were initiated thereafter.

CONCLUSION

As a rare morphology of breast cancer, breast carcinoma with OGC occurs most often in relatively young women, has less lymph node involvement, and its occurrence is not race-dependent.