Polyamine biosynthetic activity was assessed in various colorectal tissue samples consisting of noninvolved mucosa, benign adenomatous polyps and adenocarcinomas taken at surgery from a total of 40 patients. Ornithine decarboxylase (ODC) displayed a gradient of enzyme activity (i.e., adenocarcinoma greater than polyps greater than mucosa) which seemed to correlate positively with the neoplastic status of the tissue. In 10 of the patients, samples were obtained for all three tissue types. Five of these exhibited a clear repetition of the trends in enzyme activity seen with the mixed patient tissue sampling whereas the remainder differed by having the highest ODC activity in the polyps. In nine of the ten cases, ODC activity was substantially lower in the mucosa than in either of the neoplastic lesions. Trends in enzyme activity were the same for tissues obtained from either the colon or rectum. The ODC activity in adenocarcinomas could not be correlated with histologic differentiation, stage or site of the disease, however, in samples from female patients (all postmenopausal) the activity was elevated over normal mucosa to a greater extent (ten-fold) than in male patients (seven-fold). S-adenosylmethionine decarboxylase activity was assessed in 27 of the 40 patients and found to follow the same distribution as ODC; however, the mean value differences +/- SEM between tissues were less distinct. In general, tissue polyamine pool analysis of these same specimens reflected the levels of ornithine and S-adenosylmethionine decarboxylase activities. Overall, the data reveal an increase in polyamine biosynthetic activity in colorectal neoplasms, relative to surrounding mucosa, which may correlate with (1) progression of the neoplastic process, (2) the proportion of proliferating cells, (3) the rate of cell proliferation, or (4) a combination of two or all of these possibilities.
A pilot study was conducted, in which photodynamic therapy (PDT), a technique in which malignant cells are destroyed by light after being previously photosensitized by a chemical compound, was tried in a group of 14 patients with recurrent or residual colorectal cancer in the pelvis. Three of the six patients with unresectable pelvic recurrences experienced a significant relief of pain after PDT. In two of the five patients who had an incomplete resection of their pelvic recurrences, there was also a substantial relief of pelvic pain after surgery and PDT. In one of these patients subsequent biopsies proved the disappearance of the residual pelvic microscopic disease after several sessions of PDT. Three patients had a recurrence from a squamous cell carcinoma primary of the anal canal. All recurrences were amenable to surgical resection. In one of the patients, PDT was used in an attempt to sterilize an area of residual tumor that was located over the left ischial tuberosity. The patient experienced good relief of pain, but died of her disease 7 months after PDT. In the other two patients, PDT was used as an "adjunct" after resection of their recurrences. One of these patients was free of disease and died of an unrelated cause 12 months after PDT. The other is alive and well. This study demonstrated that PDT can be safe and tolerable in patients with pelvic malignancies. PDT is capable of tumor destruction, can be used repeatedly in areas previously exposed to ionizing radiation, and may have a role in the prevention and management of pelvic-perineal recurrences from colorectal cancer.
Ovarian metastases from colorectal carcinoma are seldom isolated, frequently of a large size and bilateral; and a signal for a poor prognosis for survival. This report analyzes the clinical course of patients in whom ovarian involvement was recognized and treated at the time of surgery for their primary carcinoma.
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