Basal cell carcinoma of the prostate
Other terms include 'adenoid cystic carcinoma', 'adenoid basal cell tumor', 'adenoid cystic-like tumor' etc 1.
Basal cell carcinoma of the prostate is very rare 1 and occur in a wide age range 2,3.
Typical symptoms include voiding symptoms as dysuria, nocturia, urgency other obstructive symptoms and/or enlarged or hard prostate in digital rectal examination 3,4. Prostate-specific antigen (PSA) might be normal or slightly elevated 2-4.
Basal cell carcinomas are malignant tumors arising from basal cells. Criteria differentiating them from basal cell hyperplasia are apparently not well-defined and include extensive infiltration between the glandular components, perineural invasion extraprostatic extension or necrosis 1-3.
Basal cell carcinomas are not assigned a Gleason grade 1-3.
Macroscopically tumors have been described as solid with a white and microcystic appearance 1,3.
Microscopically basal cell carcinomas of the prostate have been characterized by different growth patterns 1-4:
- pleomorphic nuclei and scant cytoplasm
- small solid nests with peripheral palisading
- cribriform spaces
- adenoid basal cell hyperplasia-like pattern
- large and solid nests with or without necrosis
Other histological features include the following:
- infiltrative permeative growth
- perineural invasion
- desmoplastic or myxoid stroma
- sparse or absent mitoses
Proliferative markers as Ki67 might help in the differentiation from basal cell hyperplasia 1,2. Other immunochemistry stains that might be positive include BCL-2, p63 and/or cytokeratin 34βE12 3,4.
Rearrangement of MYB gene has been found in a subset of basal cell carcinomas 3.
Only a few imaging descriptions can be found in the literature MRI of the prostate might show an infiltrative but otherwise uncharacteristic tumor possibly with extraprostatic extension, seminal vesicle invasion or invasion of the bladder wall if extensive 4,5 or might not show any obvious findings 6.
Possible signal characteristics include:
- T2: low to intermediate signal intensity
- DWI: diffusion restriction (hyperintense on high b-value and hypointense on ADC map)
- DCE (Gd): early enhancement
The radiological report should include a description of the following:
- form, location and size
- tumor margins
- extraprostatic extension
- seminal vesicle invasion
- bladder neck invasion
- suspicious or enlarged lymph nodes
Treatment and prognosis
Probably in part due to its rarity and its exact behavior there is apparently no real consensus on the optimal treatment. Radical prostatectomy seems to be most commonly accepted, radiation therapy and chemotherapy are other options 4. The tumor can locally recur and metastasize especially at higher stages 1,4.
Conditions mimicking the clinical presentation or imaging appearance of prostatic urothelial carcinoma include 1:
- 1. Humphrey PA. Histological variants of prostatic carcinoma and their significance. (2012) Histopathology. 60 (1): 59-74. doi:10.1111/j.1365-2559.2011.04039.x - Pubmed
- 2. Grignon DJ. Unusual subtypes of prostate cancer. (2004) Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc. 17 (3): 316-27. doi:10.1038/modpathol.3800052 - Pubmed
- 3. Begnami MD, Quezado M, Pinto P, Linehan WM, Merino M. Adenoid cystic/basal cell carcinoma of the prostate: review and update. (2007) Archives of pathology & laboratory medicine. 131 (4): 637-40. doi:10.1043/1543-2165(2007)131[637:ABCCOT]2.0.CO;2 - Pubmed
- 4. Chang K, Dai B, Kong Y, Qu Y, Wu J, Ye D, Yao X, Zhang S, Zhang H, Zhu Y, Yao W. Basal cell carcinoma of the prostate: clinicopathologic analysis of three cases and a review of the literature. (2013) World journal of surgical oncology. 11 (1): 193. doi:10.1186/1477-7819-11-193 - Pubmed
- 5. Hennes D, Dragovic A, Sewell J, Hoh MY, Grills R. Primary basal cell carcinoma of the prostate with concurrent adenocarcinoma. (2020) IJU case reports. 3 (2): 57-60. doi:10.1002/iju5.12143 - Pubmed
- 6. Shibuya T, Takahashi G, Kan T. Basal cell carcinoma of the prostate: A case report and review of the literature. (2019) Molecular and clinical oncology. 10 (1): 101-104. doi:10.3892/mco.2018.1754 - Pubmed