Prostatic malakoplakia associated with prostatic adenocarcinoma and multiple prostatic abscesses

Case report: Prostatic malakoplakia: a rare disease that has a profile mimicking prostate cancer

Prostatic malakoplakia (PMP) is a rare inflammatory disease, and misdiagnosis on imaging is a major reason for unnecessary punctures; however, information on imaging is even rarer. Five patients with PMP between May 2022 and February 2023 were enrolled in this study to summarize the imaging manifestations. All patients underwent ultrasound (US)-guided prostate biopsy and were confirmed by pathology, and the presence of prostate cancer was also excluded by pathology. The five patients, with a median age of 71 years (range = 58-74 years), had a median total prostate-specific antigen (T-PSA) of 10.40 ng/mL (range = 1.74-63.42 ng/mL). In two patients, chest computed tomography showed pulmonary infections. All patients underwent magnetic resonance imaging (MRI). Of these patients, four had a Prostate Imaging-Reporting and Data System (PIRADS) score of 5, while one had a score of 4. The lesions were mostly distributed in the peripheral zone of the prostate and appeared as a high signal on T1-weighted imaging (T1WI) and a low signal on T2-weighted imaging (T2WI). In the US examination, four patients had abnormal prostate morphology, with an unsmooth envelope and non-uniform parenchymal echogenicity. Four patients had increased prostate volume. US showed a hypoechoic nodule with non-uniform internal echogenicity, and an abundant internal blood flow signal was detected by color Doppler US. PSA, MRI, and US were not specific for PMP in our study, but we found that a history of co-infection may be helpful in an accurate diagnosis and to avoid unnecessary biopsy.

[An unusual association of malakoplakia and adenocarcinoma of the prostate]

Malakoplakia is a chronic inflammatory process caused by a lysosomal defect in bacterial digestion. Although rare, it occurs more frequently in the genitourinary tract and in patients with immune dysfunction. The bladder is the most commonly affected site, although cases have been reported in other organs, including the prostate gland. Clinically, this lesion can be confused with malignant tumours, both on physical examination and imagining techniques. This is particularly pronounced in the prostate, making the differential diagnosis challenging. Histologically, characteristic aggregates of histiocytes with basophilic intracytoplasmic inclusions composed of calcium and iron salts are found. We present a case diagnosed on transrectal biopsy as acinar adenocarcinoma with a Gleason 5 + 5 = 10 score. Prostatectomy revealed an unusual association of diffuse prostate malakoplakia and an area of acinar adenocarcinoma with a Gleason score of 3 + 4 = 7.

Exuberant Malakoplakia of the Prostate Presenting as Prostatic Abscesses in an Immunocompromised Patient

Background: Malakoplakia is a rare benign lesion, usually associated with deficient intralysosomal degradation of microorganisms, more commonly, Escherichia coli. Malakoplakia occurs in various organ systems, the most frequently affected site being the urinary bladder. We report a rare case of isolated extensive malakoplakia involving the prostate, diagnosed on transurethral resection performed for radiologically suspected prostatic abscesses. Case Presentation: A 61-year-old African American male presented with symptoms of urinary obstruction for the past 2 months. His medical history was significant for immunosuppression (liver transplantation 3 months prior and diabetes mellitus). He reported four episodes of E. coli-associated urinary tract infection after his liver transplantation. Serum prostate specific antigen was 1.83 ng/cc (normal inferior to 4 ng/cc), and urine culture was positive for E. coli sensitive to ceftriaxone. Pelvic magnetic resonance imaging was suggestive of prostatitis with prostatic abscesses; cystoscopy was unremarkable. The patient was started on intravenous ceftriaxone therapy. A standard bipolar transurethral resection of the prostate was performed, and purulent-like material was encountered in the resected tissue. Histologic examination demonstrated extensive infiltration and replacement of the prostatic tissue by sheets of pink histiocytes with targetoid inclusions consistent with Michaelis-Gutmann bodies, ultimately confirming malakoplakia of the prostate. Conclusion: Prostatic malakoplakia is an unexpected diagnosis in patients suspected of having malignancy or prostatitis. Its exact pathogenesis is unknown, but it involves defective bacterial degradation after phagocytosis. E. coli is often cultured from the patients' urine. Immunosuppression, present in our patient, is a well-known associated factor. Prostatic malakoplakia can radiologically masquerade as prostatic adenocarcinoma, despite the use of cutting-edge imaging technology. With the growing use of multiparametric 3T prostate magnetic resonance imaging to screen for prostate cancer, it is possible that urologists, radiologists, and pathologists will encounter prostatic malakoplakia more frequently in the future.

Combined occurrence of prostate carcinoma and malacoplakia

This is a case of a 56-year-old male patient suffering from a combination of prostate carcinoma and malacoplakia. A 56-year-old male patient was admitted in our Department because ischuria due to the enlargement of the prostate. Perineal needle biopsy was done resulting carcinoma of prostate. Radical prostatectomy was performed. Histology proved carcinoma and a great part of the enlarged prostate consisted of malacoplakia. Questions related to the morphology, tissue structure as well as diagnosis are briefly surveyed. This is the first report on the rarely occurring combination of prostate carcinoma and malacoplakia treated by radical retropubic prostatectomy.

Malakoplakia of the prostate gland--report of two cases and review of the literature

Malokoplakia of the prostate is extremely rare. We report two cases of prostatic malokoplakia in one 60-year-old and one 64-year-old Libyan man, who both were presented with enlarged prostate containing firm to hard nodules. These cases may be misdiagnosed as carcinoma clinically, but the histology points out the correct diagnosis with the presence of Michaelis-Gutmann bodies in the proliferating histiocytes.

Unusual Case of Prostatic Malacoplakia: Etiopathogenetic, Anatomo-clinical Considerations and Therapeutical Approach

— Malacoplakia is a granulomatous disease that is histologically characterized by the presence of Michaelis-Gutmann bodies in the macrophages. A 59-year-old man was referred to our attention for retention of urine. On digital rectal examination the left prostatic lobe was found to be increased in consistency. The PSA value was 14 ng/ml; transrectal sonography revealed a lesion of dishomogeneous pattern with hyperechoic spots at the confluence of the peripheral and transitional left zone. The smears obtained by transrectal fine needle aspiration biopsy of the lesion showed a large amount of histiocytes with the characteristic Michaelis-Gutmann bodies. The patient was treated by both surgical therapy: trans-urethral resection of the prostate (TURP-P) and pharmacological therapy: bethanechol, ascorbic acid and rifampicin. Check-ups at 3 and 6 months and subsequent transrectal sonography re-examination of the prostate revealed no evidence of relapse of the disease. The PSA value after 6 months was 3.4 ng/ml. The patient is actually in good health without recurrence of the disease. Prostatic malacoplakia must be considered as part of the differential diagnosis of prostatic nodules. Only histologic or cytologic examination leads to the proper diagnosis.

Transrectal ultrasound and biopsy in diagnosis of malakoplakia of prostate

We report our experience with the use of transrectal ultrasound and ultrasound-guided needle biopsy in the diagnosis of 4 cases of malakoplakia of the prostate. Prostatic malakoplakia is rare with a total of 25 cases reported in the literature. It may simulate carcinoma on digital rectal examination and transrectal ultrasound. Herein are 4 additional cases in which transrectal ultrasound of the prostate was compatible with carcinoma. Subsequent needle biopsy of the suspicious regions revealed the classic pathologic features of malakoplakia. Malakoplakia is a difficult pathologic diagnosis, and the prevalence of this disease may be underestimated. As the use of transrectal ultrasound becomes more common in diagnosing carcinoma of the prostate, and due to the difficulty in diagnosing malakoplakia pathologically, we recommend maintaining a high index of suspicion for malakoplakia to avoid possible unnecessary radical surgery.