Circumcision has shown no effect on PE. The International Society for Sexual Medicine guidelines do not recommend either surgical treatment due to the risk of permanent loss of sexual function and insufficient reliable data and on the basis of violating the medical principle of non-maleficence as the surgery can lead to complications, of which some might not yet be known. The most common complication of surgery is the recurrence of PE, reported to occur in about 10% of surgeries. Other sources consider SDN as a safe and efficient treatment and these surgeries are popular in Asian countries. Epidemiology
Premature ejaculation is a prevalent sexual dysfunction in men; however, because of the variability in time required to ejaculate and in partners desired duration of sex, exact prevalence rates of PE are difficult to determine. In the "Sex in America" surveys (1999 and 2008), University of Chicago researchers found that between adolescence and age 59, approximately 30% of men reported having experienced PE at least once during the previous 12 months, whereas about 10 percent reported erectile dysfunction (ED). Although ED is mens most prevalent sex problem after age 60, and may be more prevalent than PE overall according to some estimates, premature ejaculation remains a significant issue that, according to the survey, affects 28 percent of men age 65–74, and 22 percent of men age 75–85.
Cerebral spinal fluid
Criteria for CSF abnormalities include:
Increased opening pressure (> 200mm of H2O)
Increased Leukocytes (>4/mm3)
Elevated protein (>50 mg/dL)
Decreased glucose (<60 mg/dL)

Tumor markers
These markers can be good indirect indicator of NM but most are not sensitive enough to improve cytogical diagnosis:
Carcinoembryonic antigen (CEA)
alpha-fetoprotein
beta-human chorionic gonadotropin
carbohydrate antigen19-9
creatine-kinase BB
isoenzyme
tissue polypeptide antigen
Beta-2 microglobulin
beta-glucoronidase
lactate dehydrogenase isoenzyme-5
vascular endothelial growth factor

Treatment
There is currently no cure for leptomeningeal disease as the tumor is hard to eradicate. Current treatments for leptomeningeal tumors are palliative. The goals for treatment include prolonging survival and stabilizing neurological symptoms. Radiotherapy
Radiotherapy is used mostly for focal type of NM due to the nature of damage and success rate associated with the treatment. Radiotherapy targets the tumor and destroys the collective tissues of cancerous cells. Chemotherapy
Chemotherapy is injected directly into the cerebrospinal fluid, either by lumbar puncture (“spinal tap”) or through a surgically implanted device called an Ommaya reservoir. Intrathecal Therapy is preferred since intravenous chemotherapy do not penetrate the BBB. The most common chemicals used are liposomal cytarabine (DepoCyte) and intrathecal methotrexate (MTX). The downside of a spinal tap diagnosis is that while it is highly accurate and reliable, it can also report false-negative results. Chemotherapy is delivered intrathecally as it is hard for drugs to make it into the central nervous system. Intrathecal chemotherapy can only penetrate a few millimeters. If the tumor is any thicker, radiation is given to shrink it down.The treatment is done to reduce pressure on the brain caused by any cerebrospinal fluid buildup and to reduce the number of cancer cells causing the pressure.