Amyloids and brain cancer: molecular linkages and crossovers

Amyloids are high-order proteinaceous formations deposited in both intra- and extracellular spaces. These aggregates have tendencies to deregulate cellular physiology in multiple ways; for example, altered metabolism, mitochondrial dysfunctions, immune modulation, etc. When amyloids are formed in brain tissues, the endpoint often is death of neurons. However, interesting but least understood is a close connection of amyloids with another set of conditions in which brain cells proliferate at an extraordinary rate and form tumor inside brain. Glioblastoma is one such condition. Increasing number of evidence indicate a possible link between amyloid formation and depositions in brain tumors. Several proteins associated with cell cycle regulation and apoptotic pathways themselves have shown to possess high tendencies to form amyloids. Tumor suppressor protein p53 is one prominent example that mutate, oligomerize and form amyloids leading to loss- or gain-of-functions and cause increased cell proliferation and malignancies. In this review article, we present available examples, genetic links and common pathways that indicate that possibly the two distantly placed pathways: amyloid formation and developing cancers in the brain have similarities and are mechanistically intertwined together.

Surgical Management of Breast Amyloidosis

Amyloidosis is characterized by extracellular deposition of insoluble misfolded beta-pleated proteins. Amyloid disease involving the breast is rare and there is a paucity of literature guiding surgical management in caring for these patients. In this article we review medical and surgical management with an emphasis on post mastectomy breast reconstruction. We propose an algorithm for breast reconstructive options based on unique considerations in this patient population. An institutional database at the Medical College of Wisconsin was used to identify patients diagnosed with breast amyloidosis from 2011 to 2021. We utilized the electronic medical record to present patient demographics, diagnostic and treatment data regarding the medical and surgical management of these patients. Five women were identified with a median age of 70 years and a median follow up of 19 months (range, 9-80 months). All patients were diagnosed with light chain (AL) type of amyloidosis. Systemic amyloidosis was identified in 3 patients and localized disease was identified in 2 patients. Concurrent breast malignancy was identified in 2 patients who underwent skin-sparing mastectomies followed by breast reconstruction with both prosthetic and autologous techniques. Both prosthetic and autologous reconstructive techniques are safe in patients with amyloidosis, however careful consideration and preoperative work-up are warranted to avoid complications in this vulnerable population. Further studies are warranted to improve surgical outcomes in patients with amyloidosis involving the breast.

Breast amyloidosis associated with Sjögren syndrome: A diagnostic pitfall in breast pathology

BACKGROUND

Amyloidosis is an uncommon disorder characterized by the extracellular deposition of amorphous and insoluble proteins in an abnormal fibrillary configuration. Mammary amyloidosis is an unusual and easily overlooked diagnosis with an ambivalent presentation that could mimic breast cancer.

CASE REPORT

We here report the case of 60-year-old Caucasian woman who presented to our surgical oncology department for clinically and radiologically suspicious breast mass. A fine needle biopsy was irrelevant, so we performed a lumpectomy. Final histology revealed an amyloid deposit and further workup was consistent with nodular cutaneous and breast AL amyloidosis associated with Sjögren's syndrome.

CONCLUSION

Although rare, an awareness of the clinicopathologic characteristics of this easily overlooked entity is of great importance for breast surgeons.

Accumulation of amyloid beta (Aβ) and amyloid precursor protein (APP) in tumors formed by a mouse xenograft model of inflammatory breast cancer

Accumulation of amyloid in breast cancer is a well-known phenomenon, but only immunoglobulin light-chain amyloidosis (AL) or transthyretin (TTR) amyloid had been detected in human breast tumor samples previously. We recently reported that another amyloidogenic peptide, amyloid beta (Aβ), is present in an aggregated form in animal and human high-grade gliomas and suggested that it originates systemically from the blood, possibly generated by platelets. To study whether breast cancers are also associated with these Aβ peptides and in what form, we used a nude mouse model inoculated with triple-negative inflammatory breast cancer cell (SUM-149) xenografts, which develop noticeable tumors. Immunostaining with two types of specific antibodies for Aβ identified the clear presence of Aβ peptides associated with (a) carcinoma cells and (b) extracellular aggregated amyloid (also revealed by Congo red and thioflavin S staining). Aβ peptides, in both cells and in aggregated amyloid, were distributed in clear gradients, with maximum levels near blood vessels. We detected significant presence of amyloid precursor protein (APP) in the walls of blood vessels of tumor samples, as well as in carcinoma cells. Finally, we used ELISA to confirm the presence of elevated levels of mouse-generated Aβ40 in tumors. We conclude that Aβ in inflammatory breast cancer tumors, at least in a mouse model, is always present and is concentrated near blood vessels. We also discuss here the possible pathways of Aβ accumulation in tumors and whether this phenomenon could represent the specific signature of high-grade cancers.

Lactotransferrin-Related Breast Amyloidosis: Report of a First Case

Breast amyloidosis is a rare condition which is mostly associated with hematological disorders or hereditary genetic disorders. Imaging findings of breast amyloidosis can mimic malignancy, which often leads to biopsy or excision of the lesion. Here, we presented a case of localized lactotransferrin-related breast amyloidosis in an elderly female patient. Histologic examination revealed extensive involvement of breast lobules by amorphous amyloid materials, with attenuation of lobular structures and prominent calcifications. Positive immunostains for myoepithelial cells helped to exclude the possibility of invasive carcinoma. The patient had no hematologic malignancy besides immunoglobulin G lambda monoclonal gammopathy of undetermined significance. Mass spectrometry of the breast amyloid identified lactotransferrin and no immunoglobulin or its light chain. On follow-up, the patient showed no recurrence of the breast lesion after local excision nor showed other systematic comorbidities, indicating the benign nature of the lesion. This first report of lactotransferrin-related amyloidosis may represent a special type of localized breast amyloidosis that has no correlation with systematic disorders.

Localized Breast Amyloidosis Associated with Sjörgren Syndrome

Sjörgren syndrome is a systemic autoimmune disease that is rarely associated with amyloid deposits, and in most reported cases, these deposits are localized to a single organ. Amyloidosis of the breast is a rare and unexpected finding, and only 5 case series with 63 patients have been published in the past 40 years. To date, only 6 cases have been reported in which Sjörgren syndrome is associated with amyloid deposits in the breast. A 61-year-old female diagnosed with Sjörgren syndrome underwent a breast needle core biopsy for calcifications. Microscopic examination revealed amyloid deposits in the periductular basement membranes, in the walls of arteries and veins, and in the surrounding connective tissue. No malignancy was found. Clinical workup revealed the amyloid deposits to be localized to the breast and did not reveal an underlying hematolymphoid neoplasm. The association between Sjörgren syndrome and breast amyloidosis is rare, but few reports have appeared in recent years, and it may be an emerging disease association. The finding of localized amyloid in the breast and other organs should lead to a clinical workup not only for hematopoietic neoplasms but also for autoimmune diseases such as Sjörgren syndrome.

Amyloid tumor of the breast

Background

Amyloid tumor of the breast is a rare disease, which was first reported in 1973. To date, only six cases have been reported in Japan.

Case presentation

A 45-year-old woman who had a medical history of Sjogren’s syndrome presented with a lump of 3 cm in diameter on the outer side of the right breast. Mammography showed no abnormality. Ultrasonography showed a well-defined and rough hypoechoic mass of 32 mm in diameter at the site of the lump. With suspicion of breast cancer, an ultrasound-guided vacuum-assisted breast biopsy was performed. For pathological diagnosis, hematoxylin and eosin staining showed deposits of nonstructural substances in the interstitium. The specimen stained red with Congo red staining and showed green birefringence under a polarizing microscope. Thus, the mass was diagnosed as an amyloid tumor. Since the patient had Sjogren’s syndrome, it was considered a breast finding of autoimmune disease. We considered further therapy to be unnecessary, and annual follow-up was recommended.

Conclusions

We diagnosed the mass as an amyloid tumor by an ultrasound-guided vacuum-assisted breast biopsy without resection. The patient had no systemic symptoms suspected systemic amyloidosis, and we diagnosed localized amyloidosis. An amyloid tumor of the breast may show findings suggestive of breast cancer. Pathological diagnosis before surgery is important to avoid excessive invasion. If deposits of nonstructural substances are observed by hematoxylin and eosin staining, Congo red staining should be added.