What is the best treatment for prostrate enlargement BPH of 140gm & psa 6.73? Catheter insertion for one month & chronic sob, no hypertension. 72years

Simple Prostatectomy. Given your psa, a biopsy should be considered, though not imperative. Your only choices are to continue with a catheter indefinitely to see if medications eventually help, or proceed with removal of the obstructing portion of the prostate (a simple prostatectomy). This operation carries a fair amount of morbidity, but it can be done with spinal anesthesia. This would be helpful in light of sob.
Prostatectomy. Your prostate is too large to respond to medical treatment, so you need surgery. Presumeably you were in urinary retention and hence required a catheter, but, long term catheterization always results in infection. You need to in a center with reliable anesthesia, and with a urologist experienced in "open" surgery. The specimen will be reviewed by a pathologist, especially in view of the psa.
Simple prostatectomy. I agree with the first answer, but advocate a robotic simple prostatectomy to decrease blood loss and improve the urethra to bladder reconstruction.
Open prostatectomy. With a prostate that large, an open prostatectomy is probably your best choice but it depends on your surgeon.
Probably surgery. Your prostate is very big, and that might explain the high psa. Urinary retention and catheter insertion also can rise psa . I agree that the best treatment will be surgical either open or robotic prostatectomy . Your prostate is too big for trans-urethral resection ( turp). If your psa remains high, a prostate biopsy is needed to rule out prostate cancer.