Prostate gland & seminal vesicles

Inflammation

Granulomatous lesions


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Y. Albert Yeh, M.D., Ph.D.

Last staff update: 28 June 2022

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PubMed search: Prostatic granulomatous lesions

Y. Albert Yeh, M.D., Ph.D.
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Cite this page: Yeh YA. Granulomatous lesions. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/prostategranprostgeneral.html. Accessed July 6th, 2022.
Definition / general
  • Uncommon entity of inflammation with formation of granuloma(s) in the prostate (Prostate Int 2017;5:29)
  • First described by Tanner and McDonald in 1943 (cited in Urol Int 1988;43:97)
  • Classification includes nonspecific granulomatous prostatitis, infectious granulomas, postsurgical granulomas, systemic granulomatous prostatitis, xanthogranulomatous prostatitis and malakoplakia (Hum Pathol 1984;15:818)
Essential features
  • Classification includes nonspecific granulomatous prostatitis, infectious granulomas, postsurgical granulomas, systemic granulomatous prostatitis, xanthogranulomatous and malakoplakia prostatitis (Hum Pathol 1984;15:818)
  • Nonspecific granulomatous prostatitis: dilated ducts and acini filled with histiocytes, foamy macrophages, neutrophils, lymphocytes and rare multinucleated giant cells (Figures 1 - 3)
    • Surrounded stroma consists of heavy mixed inflammatory infiltrate composed of epithelioid histiocytes, neutrophils, lymphocytes, plasma cells, rare eosinophils and occasional multinucleated giant cells (Figure 4)
  • Postsurgical granuloma: multiple granulomas with or without caseating necrosis, palisading histiocytes, lymphocytes and Langhans giant cells (Figure 7)
ICD coding
  • ICD-10:
    • N41.4 - granulomatous prostatitis
    • N41.1 - chronic prostatitis
  • ICD-11:
    • GA91.0 - chronic prostatitis
    • GA91.Y - other specified inflammatory and other diseases of prostate
Epidemiology
  • 1 - 2% of prostate specimens (Prostate Int 2017;5:29)
  • Nonspecific granulomatous prostatitis: most common type (> 50% of cases)
  • Affect ages: from 18 to 86 years old, mean and median age of 62 years
Sites
Etiology
  • Nonspecific granulomatous prostatitis: a reaction to bacterial toxins, cellular debris and glandular secretions spilling into the stroma from destructive ducts or acini (J Urol 2012;187:2209)
  • Infectious prostatitis:
  • Postprocedural granuloma: a reaction to the alteration of epithelium and stroma caused by the trauma from previous surgical procedure (Am J Surg Pathol 1984;8:217)
  • Foreign body granuloma: introduction of foreign material or destruction of glands with prostatic secretions spilling into the stroma
  • Systemic: sarcoidosis, granulomatosis with polyangiitis (Wegener granulomatosis), eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome), allergic prostatitis, allergic (eosinophilic) prostatitis (J Clin Pathol 2007;60:325)
  • Xanthogranulomatous: possibly caused by destruction of ducts or acini (Am J Case Rep 2021;22:e932869)
  • Malakoplakia: bactericidal defect in macrophages (Case Rep Pathol 2014;2014:150972)
Clinical features
  • Symptoms include urinary frequency, urgency or hesitancy as well as burning micturition, dysuria, fever and chills (Prostate Int 2017;5:29)
  • May be asymptomatic
  • Hematuria
  • Firm and fixed nodule on digital rectal examination, urinary obstruction in severe cases
  • Serum PSA ranging from 0.5 ng/mL to 114 ng/mL (mean 12.7 ng/mL) (Arch Pathol Lab Med 1997;121:724)
Diagnosis
  • Chronic granulomatous inflammation by histopathological examination of the prostate (Hum Pathol 1984;15:818)
  • Xanthogranulomatous: presence of foamy macrophages by microscopic examination (Res Rep Urol 2016;8:165)
  • Malakoplakia: calcified and lamellated Michaelis-Gutman bodies (Case Rep Pathol 2014;2014:150972)
  • Infectious: identify microorganisms on special stains, positive microbiologic cultures
  • Postprocedural: previous history of prostatic biopsy, transurethral resection of prostate (TURP), introduction of foreign material, intravesical BCG immunotherapy (J Urol 2012;188:961)
  • Systemic: other organ systems involved by granulomas
  • Nonspecific granulomatous prostatitis: histopathological features (J Urol 2012;187:2209)
Laboratory
Radiology description
  • Transrectal ultrasound of the prostate reveals hypoechoic lesions mimicking adenocarcinoma (Ultrason 2016;16:404)
  • Magnetic resonance imaging of the prostate reveals hypointense lesions mimicking adenocarcinoma (Radiology 2018;289:267)
Radiology images

Images hosted on other servers:
Prostatic hypoechoic lesion (ultrasound)

Prostatic hypoechoic lesion (ultrasound)

Prostatic hypointense lesion (MRI)

Prostatic hypointense lesion (MRI)

Case reports
Treatment
  • Warm sitz baths, fluids and antibiotics (if there is a urinary tract infection) for nonspecific granulomatous prostatitis
  • Antibiotics for infectious prostatitis (Prostate 2020;80:1006)
  • Prednisone for granulomatosis with polyangiitis, prednisone plus either rituximab or cyclophosphamide for severe disease (N Engl J Med 2010;363:221)
  • Simple prostatectomy or transurethral resection (TURP) to relieve obstructive symptoms
Clinical images

Images hosted on other servers:
Xanthogranulomatous prostatitis with abscess

Xanthogranulomatous
prostatitis with
abscess

Gross description
  • Nonspecific appearance; may be hard and nodular
Microscopic (histologic) description
  • Nonspecific granulomatous prostatitis: dilated ducts and acini filled with histiocytes, foamy macrophages, neutrophils, lymphocytes and rare multinucleated giant cells (Figures 1 - 3) (Hum Pathol 1984;15:818)
    • Surrounded stroma consists of heavy mixed inflammatory infiltrate composed of epithelioid histiocytes, neutrophils, lymphocytes, plasma cells, rare eosinophils and occasional multinucleated giant cells (Figure 4)
  • Foreign body granuloma: foci of destructive acini filled with multinucleated (foreign body type) giant cells with fusion forms, some lymphocytes and histiocytes (Figures 5 - 6)
  • Infectious granuloma: multiple granulomas with or without necrosis, positive staining with Gram, AFB, PAS or GMS special stains
  • Postsurgical granuloma: multiple granulomas with or without caseating necrosis, palisading histiocytes, lymphocytes and Langhans giant cells (Figure 7)
  • Systemic granulomatous disease: multiple granulomas composed of Langhans giant cells, epithelioid histiocytes and lymphocytes (Figures 8 - 11), mainly eosinophils in allergic (eosinophilic) prostatitis
Microscopic (histologic) images

Contributed by Y. Albert Yeh, M.D., Ph.D.
Dilated ducts with inflammation Dilated ducts with inflammation

Dilated ducts with inflammation

Histiocytes and giant cells

Histiocytes and giant cells

Expansile inflammatory areas

Expansile inflammatory areas

Foreign body giant cells Foreign body giant cells

Foreign body giant cells


BCG related giant cells

BCG related giant cells

Sarcoid related lesions

Sarcoid related lesions

Sarcoid related giant cells

Sarcoid related giant cells

Sarcoid related Langhans cells Sarcoid related Langhans cells

Sarcoid related Langhans cells



Contributed by Ximing J. Yang, M.D., Ph.D.
Multiple granulomas

Multiple granulomas

Langerhans giant cells

Langhans giant cells

BCG induced granuloma

BCG induced granuloma

Foreign body giant cell granuloma

Foreign body giant cell granuloma

Indeterminate granuloma

Indeterminate granuloma

Positive stains
Sample pathology report
  • Prostate, needle core biopsy:
    • Granulomatous inflammation consistent with nonspecific granulomatous prostatitis (see comment)
    • Comment: The prostate biopsy shows prostatic tissue with dilated destructive ducts filled with epithelioid histiocytes, foamy macrophages, neutrophils and lymphocytes. Some areas in the stroma consist of heavily mixed inflammatory infiltrate composed of histiocytes, neutrophils, lymphocytes and plasma cells. Occasional multinucleated (Langhans type) giant cells are seen. There is no caseating necrosis. AFB special stain is negative for mycobacteria. PAS and GMS stains are negative for fungal organisms. With no known clinical history of systemic granulomatous disease, this lesion is consistent with nonspecific granulomatous prostatitis
Differential diagnosis
Board review style question #1
Which of the following is the most common type of granulomatous lesion of the prostate?

  1. Infectious granulomas
  2. Nonspecific granulomatous prostatitis
  3. Postsurgical granulomas
  4. Systemic granulomatous prostatitis
Board review style answer #1
B. Nonspecific granulomatous prostatitis

Comment Here

Reference: Granulomatous lesions
Board review style question #2

A 60 year old man presented with dysuria, fever, chills and progressive increase in PSA level. Prostatic biopsy is performed. Special stains including Gram, AFB, PAS and GMS are negative for microorganisms. Von Kossa stain and Prussian blue stain are negative. A photomicrograph is shown above. What is the diagnosis?

  1. Adenocarcinoma associated with granuloma
  2. Malakoplakia with granuloma
  3. Nonspecific granulomatous prostatitis
  4. Prostatic adenocarcinoma, giant cell type
Board review style answer #2
C. Nonspecific granulomatous prostatitis

Comment Here

Reference: Granulomatous lesions
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