Elevated prostate markers in metastatic small cell carcinoma of unknown primary

A Case of Advanced Submandibular Gland Cancer in Which Increased Prostate-Specific Antigen and Multiple Bone Metastases Wrongly Suggested Concurrent Prostate Cancer

A 73-year-old man, followed for prostatic hyperplasia, developed submandibular gland cancer. Initially, because of the concurrent presence of elevated serum prostate-specific antigen (PSA) and multiple bone metastases, he was clinically determined as having stage IV prostate cancer in addition to stage II submandibular gland cancer, and radical surgery for his submandibular gland cancer was performed first. However, subsequent detailed examinations of the prostate gland showed no prostate cancer, and a diagnosis of advanced submandibular gland cancer with increased PSA and multiple bone metastases was established. Serum PSA is highly specific for prostate diseases and is widely used as a tumor marker of prostate cancer. However, clinicians should be aware that, in patients with non-prostate cancer, the detection of increased PSA and multiple bone metastases does not necessarily indicate the concurrent presence of prostate cancer.

Complete chemotherapeutic regression of a non-metastatic case of primary pure small cell carcinoma of the prostate

Pure small cell carcinoma of the prostate (SCPCa) is a very rare condition usually with poor survival after diagnosis. It seems to show different clinical features compared to other prostate cancer subtypes, specifically adenocarcinoma. Here, we present a 74-year-old man early diagnosed with SCPCa treated with a cisplatine and etoposide regimen. There was no metastasis found in imaging studies and bone scan. The patient mostly complained of obstructive symptoms which were relieved after resection. Interestingly, our patient experienced a disease free condition after chemotherapy and no further progression was found. This could implicate the critical role of early diagnosis in the treatment of SCPCa despite its aggressive nature.

A case of robot-assisted laparoscopic radical prostatectomy in primary small cell prostate cancer

Primary small cell carcinoma of the prostate is a rare and very aggressive disease with a poor prognosis, even in its localized form. We managed a case of primary small cell carcinoma of the prostate. The patient was treated with robot-assisted laparoscopic radical prostatectomy and adjuvant chemotherapy. Herein we report this first case of robot-assisted laparoscopic radical prostatectomy performed in a patient with primary small cell carcinoma of the prostate.

Prostate carcinoma presenting as multiple pulmonary nodules in an asymptomatic patient with a history of testicular nonseminomatous germ cell tumor

Prostate carcinoma presenting initially as multiple pulmonary nodules in an asymptomatic patient without previous prostate carcinoma is unusual. Whether the incidence of prostate carcinoma is significantly increased in patients treated previously for germ cell tumors is unclear. We report such a patient, who responded to combination androgen blockade therapy.

Raised prostate-specific antigen in adenocarcinoma of the colon

Serum prostate-specific antigen (PSA) values above 10 ng/ml are considered highly sensitive and specific for prostatic carcinoma in the absence of prostatic inflammation or trauma. However, in rare instances, non-prostatic malignancies have also been associated with raised serum PSA values. We have encountered a patient with increased serum PSA concentration measured by monoclonal antibody assay who had no evidence of prostatic malignant involvement, but suffered from colon cancer. Before operation for colon cancer his PSA was always over 30 ng/ml on several examinations. After total removal of colon cancer serum PSA level fell down to 1.2 ng/ml. Although immunohistochemical staining of colon cancer with monoclonal PSA antibody was not performed, some relationship between raised PSA and colon cancer is strongly suspected. Substances like serine protease which can cross-react with the PSA antibody might be produced by malignant tumour of non-prostatic origin.

Constitutive expression of high levels of prostate-specific antigen in the absence of prostate carcinoma

OBJECTIVES

To identify distinguishing serologic features in patients with stable marked elevation in prostate-specific antigen (PSA) and multiple negative biopsies.

METHODS

The study population consisted of 7 patients with a stable PSA level of greater than 20 ng/mL (average 27.0), followed for at least 34 months (average 56), and with two or more negative prostatic biopsies including transition zone biopsies. The PSA density (PSAD), rate of change in PSA, reverse transcriptase/polymerase chain reaction (RT/PCR), and free/total PSA were obtained.

RESULTS

Rate of change in PSA level was stable (0.18 +/- 1.2 ng/mL/yr), suggesting that there was no occult cancer; PSAD was high (0.34 +/- 0.5 ng/mL/cc), indicating that prostate size was not the sole cause of the elevation. The RT/PCR was negative in 6 of 7 patients, further decreasing the likelihood of an occult malignancy. Free versus total PSA was not consistent, averaging 16.8%, but with a range of 6% to 34%.

CONCLUSIONS

Novel PSA tests were not found to be useful in this cohort of patients with multiple negative biopsies and PSA elevations greater than 20 ng/mL. Additional studies with larger sample size are required to confirm this finding.

A guide to the interpretation of serum prostate specific antigen levels

OBJECTIVE

To review the factors that affect the concentration of prostate specific antigen (PSA) in the serum.

RESULTS

The discussion includes the structure of PSA; its distribution and metabolism; various analytical aspects of PSA measurements; the effects of clinical manipulations on PSA, including digital rectal examination, transrectal ultrasound, cystoscopy, biopsy and transurethral resection of the prostate; factors affecting PSA levels in health, in benign disease, and in prostate cancer; the effect of various treatments on PSA; and the issue of reference ranges.

CONCLUSION

Laboratory staff and physicians must take many factors into consideration when interpreting PSA results.

False-positive serum prostate-specific antigen values in a patient with non-Hodgkin lymphoma of the kidney

Prostate-specific antigen (PSA) is the clinically most useful tumor marker for prostate cancer. Although false-positive elevations have been reported due to disease processes outside the prostate gland with the use of the polyclonal assay, such false-positive test results have been exceedingly rare with the use of the monoclonal assay. We report the case of a patient diagnosed with a B-cell lymphoma of the kidney and a significant elevation of serum PSA levels by monoclonal assay in the absence of either inflammatory or malignant prostate disease. PSA returned to normal during lymphoma-specific chemotherapy with a cyclophosphamide, mechlorethamine, vincristine, procarbazine, prednisone regimen. Possible explanations and clinical implications are discussed.