Histopathologic examination showed epithelioid and giant cell granulomas with caseous necrosis.
A 69-year-old man without a known history of tuberculosis was evaluated for acute urinary retention and irritative lower urinary tract symptoms. Digital rectal examination showed an enlarged, firm, nodular prostate. Serum PSA was elevated at 27 ng/mL. Pelvic ultrasonography demonstrated marked prostatic enlargement, estimated at 90 mL. Given the clinical suspicion for malignancy, surgical management was pursued.
The patient underwent prostatic adenomectomy. Examination of the surgical specimen showed firm, whitish nodules with focal yellowish areas. Histopathologic evaluation demonstrated adenomyomatous hyperplasia of the prostate with no morphologic signs of malignancy. Additionally, the prostatic parenchyma contained epithelioid and giant cell granulomas with caseous necrosis, leading to a diagnosis of caseous follicular tuberculosis associated with adenomyomatous hyperplasia.
This case illustrates a diagnostic pitfall in which prostatic tuberculosis closely mimicked prostate cancer. The combination of an enlarged, firm, nodular prostate on digital rectal examination and elevated PSA raised clinical suspicion for malignancy. Without histopathologic confirmation, this patient might have been subjected to inappropriate cancer-directed therapy. The researchers emphasized that pathological examination has an essential role in establishing the correct diagnosis and preventing such mismanagement.
“The misleading clinical presentation can mimic prostate adenocarcinoma,” noted lead study author Lalaina Nomenjanahary of the Department of Pathology at Joseph Ravoahangy Andrianavalona University Hospital in Antananarivo, Madagascar, and colleagues.
Prostatic tuberculosis is a rare form of genitourinary tuberculosis. Spread of Mycobacterium tuberculosis to the prostate is most often hematogenous from pulmonary or renal sources. Notably, this case represents an example of extrapulmonary tuberculosis presenting without identified pulmonary involvement, which poses additional diagnostic challenges for infectious disease specialists. No other site of tuberculosis was identified in this patient.
The researchers noted that polymerase chain reaction (PCR) testing, including GeneXpert MTB/RIF, improves diagnostic sensitivity to 95%. However, histopathologic confirmation showing epithelioid and giant cell granulomas with caseous necrosis remains the key to diagnosis.
Following diagnosis, the patient was treated with antituberculous chemotherapy consisting of isoniazid, rifampicin, pyrazinamide, and ethambutol for 2 months, followed by isoniazid and rifampicin for 4 months. Evaluation identified no additional sites of tuberculosis.
The researchers reported no conflicts of interest regarding the publication of this case report.
Source: Open Journal of Pathology