Low accrual rate.

Primary Objective:

1. To determine the prevalence of secondary hypogonadism in male patients on chronic opioid therapy for cancer-related pain syndromes.

Secondary Objective:

1. To determine the degree of sexual dysfunction, fatigue, and depression prevalent in male patients on chronic opioid therapy for cancer-related pain syndromes.

Studies have shown that non-cancer patients taking opioid pain medication for a long period of time can have decreased libido and decreased sexual function.

Individuals may be asked to take part in this study even if they have not taken opioid pain medications in the last twelve months. These individuals would also be enrolled to learn if long-term treatment of cancer-related pain with opioid medications results in decreased sex hormones, decreased sex drive, and increased fatigue or depression.

Participants in this study will be asked to complete a set of questions about their sexual functions, physical symptoms, and psychological symptoms such as fatigue and depression. It will take about 25 minutes to complete the questionnaires.

Participants will have blood drawn (about 2 teaspoons of blood) to test their sex hormone level. Participants who are identified as having low sex hormone level (hypogonadism) will be referred to an endocrinologist for standard hormone replacement therapy.

This is a one-time evaluation, no follow-up visit or questionnaires are required.

This is an investigational study. A total of 108 individuals will take part in this study. All will be enrolled at UTMDACC.

Inclusion Criteria:

1. Chronic pain greater than one year.
2. Male.
3. Cancer status must be stable or in remission. For this study, "stable disease" is defined as identifiable disease at local or metastatic sites that has shown no progression over the previous 3 months and there has been no cancer treatment for ³ 3 months.
4. Patients must be on chronic opioid therapy on a continuous basis in the preceding twelve months with a Morphine Equivalent Daily Dose (MEDD) ³ 200.
5. Age >/= 18. The questionnaires used in this study have been validated only in the adult population. In addition, some of the questionnaires contain questions of a sensitive nature and are not appropriate in the pediatric population.
6. Patients must be able to understand and sign the consent form.

Exclusion Criteria:

1. Patient who refuses to participate in the study or determined incapable of completing the research.
2. Patients with pre-existing hypopituitarism. Causes include certain tumors (pituitary adenomas, hypothalamic tumors), inflammatory diseases (granulomatous diseases), vascular diseases (postpartum necrosis, carotid aneurysm), traumatic/destructive events (prior surgery, trauma, or radiation), developmental anomalies, infiltration.
3. Patients who tare taking any drugs that may affect the hypothalamic-pituitary-gonadal axis.

Males on chronic opioid therapy for cancer-related pain syndromes.