They discover how to diagnose a "ghost" disease early

Amyloidoses are a group of diseases in which different types of proteins fold abnormally, are deposited in the tissues and end up compromising their function. These deposits can be local or systemic.

Although little known only 25 years ago, it is currently considered that TTR amyloidosis (due to transthyretin protein deposition) is the most frequent form of systemic amyloidosis associated with aging. Formerly known as senile cardiac amyloidosis, we now know that deposits can be found in various organs and tissues, years before cardiac symptoms appear, which can become serious.

Early diagnosis of this form of systemic amyloidosis is difficult because its main symptoms often overlap and are confused with normal manifestations of aging. That is why, in a certain way, it has been a “ghost” disease.

An investigation led by Dr. Maria Pané and Dr. Enric Condom, from the Pathological Anatomy Service of the Bellvitge University Hospital (HUB) and researchers from the Bellvitge Biomedical Research Institute (IDIBELL), located in Hospitalet de Llobregat and which forms part of the CERCA institution of the Generalitat of Catalonia, and in which the Radiology, Urology and Internal Medicine services of the aforementioned hospital have also participated, has made it possible to verify that the prostate is one of the tissues in which amyloid is deposited in cases of systemic amyloidosis (especially of the TTR type), something very little known until now.

The authors of the study incidentally found amyloid deposits in prostate biopsies from 40 patients, among thousands of biopsies performed for suspected prostate cancer between 2001 and 2022. The immunohistochemical study confirmed the finding and determined the type of amyloid in more than 80% of cases. The majority corresponded to TTR amyloid. Only four of the patients had a previous diagnosis of systemic amyloidosis (all of them not TTR).

The study has confirmed that the prostate is one of the tissues in which amyloid is deposited in cases of systemic amyloidosis (especially of the TTR type). (Photo: IDIBELL / Bellvitge University Hospital)

Reviewing the medical records of patients in whom amyloid deposition had been detected, the study authors found that all had at least one of the symptoms described as characteristic of TTR systemic amyloidosis: bilateral carpal tunnel syndrome, loss of auditory and osteoarticular problems (tendinopathies, lumbar canal stenosis, osteoarthritis), among others.

This is the largest series published to date of patients diagnosed with amyloidosis in the prostate. As explained by Dr. Maria Pané, principal investigator of the work, “the potential clinical impact and the benefit that we can obtain from this incidental diagnosis is important, because an undetermined percentage of patients with TTR systemic amyloidosis end up developing heart disease, which if it is diagnosed and treated early, it allows a significant improvement in the quality of life and survival of patients”.

In addition to showing that the prostate is a target tissue for amyloid deposits, the HUB’s work also aims to contribute to disseminating among professionals the clinical picture of TTR systemic amyloidosis, which presents above all with musculoskeletal and neurosensory symptoms and emphasizing that not all patients with this form of amyloidosis have cardiac involvement.

Additionally, it is advisable to review any biopsy sample in patients with suspicious symptoms of systemic amyloidosis, in order to try to detect amyloid deposits that would have gone unnoticed, advises Dr. Pané.

The study is titled “Clinical relevance of amyloid in prostate samples: a report on 40 patients.” And it has been published in the academic journal Histopathology. (Source: IDIBELL)