Well-differentiated neuroendocrine tumor of the prostate

Dr Joachim Feger et al.

Well-differentiated neuroendocrine tumors of the prostate also known as low-grade neuroendocrine carcinoma of the prostate or carcinoid tumors of the prostate are low-grade neuroendocrine tumors arising from the prostate that may metastasize.

Well-differentiated neuroendocrine tumors of the prostate are exceedingly rare 1-3.

A connection of well-differentiated neuroendocrine tumors with multiple endocrine neoplasias (MEN 2b) has been made in some of the cases 2-4.

Prostate specific antigen (PSA) as per definition should be negative and well-differentiated neuroendocrine tumors of the prostate might present with other symptoms as voiding difficulties, dysuria. They might be also found incidentally on a histologic specimen or in conjunction with a prostate adenocarcinoma 4.

Well-differentiated neuroendocrine tumors of the prostate show a similar tumor morphology as carcinoid tumors from other organs like the lung bladder or gastrointestinal tract and are clearly different from usual prostate cancer. They are characterized by the following features 1-4:

  • origin from prostate parenchyma and not from other organs
  • distinct from prostate adenocarcinoma (that might coexist)
  • positivity for neuroendocrine markers (synaptophysin, chromogranin A or CD56) and negativity for prostate specific antigen (PSA)

Microscopically well-differentiated neuroendocrine tumors of the prostate might display the following histological features 1,2,5:

  • polygonal spindle-shaped cells
  • small uniform nuclei
  • microacinar or rosette-like growth pattern
  • mixed architecture

Immunohistochemistry stains are usually positive for at least one neuroendocrine marker as synaptophysin, chromogranin A or CD56. They are negative for prostate specific antigen (PSA) 1-4 and the Ki67 index is usually low. Some carcinoid tumors might express prostate-specific acid phosphatase 1-3.

Due to their very rare occurrence, there are no suitable radiological descriptions of pure carcinoid of the prostate as yet. So if you come across such a rare entity with a histologically verified diagnosis please feel free to publish your case here and give us a description of your findings.

The radiological report should include a description of the following features:

  • form, location and size
  • tumor margins
  • associated prostate cancer

Well-differentiated neuroendocrine tumors of the prostate are considered low-grade tumors but they are malignant and might metastasize to pelvic lymph nodes liver lungs or bone 4. Due to their rarity, there seems to be no consensus on the optimal treatment in cases without concomitant prostate cancer. Radical prostatectomy with follow up has been adopted in one case on 34-year-old man 4.

The first primary carcinoid tumor of the prostate was described by PW Wasserstein and RL Goldman in 1979 3,6.

Conditions and tumors that can mimic the clinical presentation or imaging appearance of well-differentiated neuroendocrine tumors of the prostate include 1:

Article information

rID: 88326
Tag: cases3
Synonyms or Alternate Spellings:
  • Well-differentiated prostatic neuroendocrine tumour
  • Prostatic carcinoid tumour
  • Carcinoid tumour of the prostate
  • Well-differentiated neuroendocrine tumours of the prostate
  • Low-grade neuroendocrine carcinoma of the prostate

ADVERTISEMENT: Supporters see fewer/no ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.