Cancer of the prostate gland is one of the most frequent and hurtful tumors that affect the male population. The large majority of prostate cancers are represented by adenocarcinomas, whereas less percent of people develop squamous, transitional, signet ring cell and other types of prostate cancers. Prostate adenocarcinomas lead to the absence of the basal cell layer in the prostate and the presence of abnormal mitosis.
Acinar adenocarcinomas are the most common form of the cancer of prostate gland . Adenocarcinoma of the prostate expresses immunohistochemical markers of prostatic tissue, prostate specific antigen, prostatic acid phosphatase, androgen receptor and cytokinins.In one study, the tumor was characterized by two features, firstly, high grade infiltrating acinar adenocarcinoma with gleason score of 8 or 9 and secondly, intraductal carcinoma which is characterized by the malign epithelial cells filling dilated ductal acinar structures surrounded by basal cells. Ductal adenocarcinomas of the prostate develop from the prostatic urethra and it is one of the many exophytic lesions that may present in the prostatic urethra of aged men and include benign and malignant lesions of the prostate gland of urothelial.
The majority of ductal adenocarcinomas are found to be linked with the components of acinar and having a tumor with all the components of ductal is the very rare case. Ductal adenocarcinomas usually arise from the primary periurethral prostatic ducts, whereas acinar adenocarcinomas arise from other periurethral prostatic ducts. Also, ductal adenocarcinomas consist of columnar cells that are arranged in one of the pattern, papillary or cribriform and on the other hand acinar adenocarcinomas exhibits the cuboidal cells that are arranged in acini. When the ductal cells are arranged in the papillary pattern, it is composed of true papillary fronds that are lined by the columnar cells that exhibit nuclear pleomorphism and hyperchromasia. The other patterns are made up of proliferating large, back to back cribriform glands with central necrosis.
Squamous Cell Carcinoma is a rare condition and it is more malignant than adenocarcinomas. Most of the time an abnormal change in the nature of tissues that occurs in the prostate in chronic prostatitis, after estrogen or radiation therapy, and around the prostatic infarcts has been misdiagnosed to be primary squamous cell carcinoma. According to the studies, there is a strict criterion to diagnose primary cell carcinoma of the prostate:
- A malignant abnormal growth that is characterized by invasion, disordered growth and cellular anaplasia.
- Clear squamous features of keratinization, squamous pearls, and numerous distinct intercellular bridges.
- Lack of glandular and acinar pattern.
- No prior estrogen therapy.
- An absence of primary squamous cancer anywhere else and especially squamous cancer of the bladder.
The risk of developing squamous cell carcinoma of the prostate is less and it is very aggressive as compared to ordinary adenocarcinomas. The basal cells of the prostatic acini and the transitional epithelia lining major ducts are presumed to be involved in the development of squamous cell carcinoma of the prostate.
Transitional cell carcinoma of the prostate is a carcinoma of the urothelial origins. The transitional cell carcinoma of the prostate is rarely primary and it usually represents synchronous and metachronous from carcinomas of bladder and urethra. The primary transitional cell carcinoma of the prostate involves the whole prostatic urethra and particularly the areas which are near the verumontanum, the large prostatic duct, and areas nearby to acini. According to the researchers, it is presumed that cancer arises from the urothelium lining the prostatic urethra and the proximal portion of the prostatic ducts and they also suggest that the tumor that originates in the prostate can also result in the malignant transformation of the prostatic urothelium.
Signet ring cell carcinoma of the prostate is a very rare type of malignant tumor and very few cases of this type of prostate cancer have been diagnosed. Signet cell carcinoma of the prostate is characterized by an intracytoplasmic vacuole compressing the nucleus into a crescent shape at the cellular level. These tumors lead to an elevated PSA level and it also exhibits highly aggressive behavior as compared to other adenocarcinomas of the prostate. Also, various studies suggest that patients who develop signet ring cell carcinoma live only for a few years after resection. Patients who suffer from the signet ring cell carcinoma often complains of obstructive urinary symptoms. When the signet cells of carcinoma originate in the prostate, immunohistological and histological stains can help in making a correct diagnosis.