Calcification in colorectal hepatic metastases correlates with longer survival.

BACKGROUND: Calcification occurs in 12-27% of hepatic colorectal metastases, but its clinical significance and its influence on prognosis are unknown. METHODS: All patients diagnosed with colorectal liver metastases at the Ottawa Regional Cancer Center in 1991 (n = 97), as well as those enrolled in chemotherapy trials in 1990-1992 (n = 51), were entered into a retrospective cohort study. Thirty-six patients were excluded due to inadequate follow-up. In the remaining 112, abdominal CT scans and/or ultrasound examinations were used to determine the presence of calcification. Charts were reviewed for variables, including primary tumour pathology, amount of liver involvement by tumour (< 25%, 25-50%, > 50%), and the chemotherapeutic agents received, and were subjected to multivariate and regression analysis. End point was survival in months or to December 1993 (median follow up 24 months). RESULTS: Patients with calcification (n = 31) (28%) were compared to those who did not have calcifications (n = 81). The groups were comparable with respect to sex, age, time to calcification, time to metastases, and treatment type. Calcification occurred independent of the degree of tumour differentiation, the presence of mucinous adenocarcinoma, or the hepatic tumour burden. Nine patients with calcified metastases (30%) had calcification at presentation. Biopsies showed calcification next to viable tumour cells with an absence of an inflammatory reaction. Survival was improved with better primary tumour differentiation and less tumour burden. The presence of calcification had a statistically highly significant improvement in survival (P < 10(-6), relative risk = .19) independent of other variables. CONCLUSIONS: The presence of calcification within a colorectal liver metastasis appears to imply a significantly better prognosis.

Computed tomographic and cytologic assessment of cystic pancreatic neoplasms: a difficult preoperative diagnosis.

The computed tomography (CT) findings or cytologic results, or both, for 21 patients with cystic pancreatic neoplasm (4 with microcystic cystadenoma, 6 with macrocystic mucinous cystadenoma, 10 with macrocystic mucinous cystadenocarcinoma and 1 with a papillary cystic neoplasm) were reviewed. CT scans for 14 of the patients were reviewed by two gastrointestinal radiologists who were blinded with respect to the patients' identities and the diagnoses. The radiologists used previously published criteria for distinguishing between microcystic and macrocystic neoplasms. Of the four cases of microcystic cystadenoma, two were correctly diagnosed by one radiologist, and one was correctly diagnosed by the other. Three and four cases respectively of five cases of macrocystic cystadenoma were correctly identified, as were three and five of five cases of macrocystic cystadenocarcinoma. Cytologic evaluation of samples from fine-needle aspiration biopsy had been performed for 15 of the patients, and these records were reviewed. One of three cases of microcystic cystadenoma, two of four cases of macrocystic cystadenoma, five of seven cases of macrocystic cystadenocarcinoma and the papillary cystic neoplasm were correctly diagnosed on the basis of the cytologic findings. The combination of CT and cytologic assessment is helpful in distinguishing different types of cystic pancreatic neoplasms, but there is significant overlap among the clinical and radiographic features of these lesions, and therefore operative assessment is often necessary.

A comparison between expanded polytetrafluoroethylene and plasma tetrafluoroethylene grafts for hemodialysis access.

Animal studies have indicated that plasma tetrafluoroethylene (TFE) may be a better prosthetic material than expanded polytetrafluoroethylene (ePTFE) for arteriovenous access in patients who require hemodialysis because it combines the advantages of both Dacron and Teflon. A randomized clinical trial to compare the two materials was conducted between May 1987 and January 1989. Forty-four patients were enrolled, 22 in each group. The status of the grafts was monitored for at least 18 months. The patency rate for plasma TFE was 59% and for ePTFE was 64%. Kaplan-Meier analysis and Wilcoxon testing revealed no statistical differences between the two groups. Four grafts became infected, two in each group, and one aneurysm developed. Despite its theoretical advantages, plasma TFE was found to be similar to ePTFE as a graft material for hemodialysis.

Immunodeficiency following splenectomy in the early postimmunization period.

Splenectomy is associated with an increased risk of serious infection with encapsulated micro-organisms in a small number of individuals. The immunological defects in this state are unclear. We have investigated in rabbits the effect of splenectomy, before and after primary immunization with a specific antigen (sheep erythrocytes) similar in structure to the pneumococcal capsular antigen, on the organ localization of antibody forming cells and the long-lived memory cells. Antibody forming cell and memory cell assays were performed at intervals up to day 270 after primary immunization. Antibody titres following secondary immunization were also measured. The results show that the major site of antibody forming cells is in the spleen following primary immunization of the untreated rabbit and that antibody forming cells subsequently migrate to the lymph nodes and thymus. On the other hand, in rabbits splenectomized before primary immunization the major site of the antibody forming cells is the peripheral lymph nodes. These rabbits also gave good secondary immune responses. However, splenectomy 40 days after primary immunization results in a poor secondary immune response, indicating that essentially all the antibody forming cells following primary immunization were localized in the spleen at the time of splenectomy.

Crohn's disease angiographically mimicking vascular malformation or neoplasm.

We report a young woman with lower gastrointestinal bleeding in whom, angiographically and surgically, the offending cecal lesion appeared to be a vascular malformation or neoplasm. Pathologically, Crohn's disease associated with extremely prominent vascularity was discovered to be responsible for this unusual appearance and the bleeding.

Perforated ulcers in critical illness.

Although gastroduodenal ulcers rarely perforate during critical illness, this occurrence causes specific and difficult problems of diagnosis and management. In our review of the records of 19 critically ill patients whose ulcers perforated, we found that classical symptoms were frequently absent. The perforations often were manifested by nonspecific clinical events, such as unexplained ileus or hypotension. Diagnosis was typically delayed and on occasion was first suspected after observing pneumoperitoneum on a routine x-ray. While the ulcers were characteristically very large (greater than 2 cm), minimal inflammation surrounded them. Mortality was 56% in the 16 patients whose perforations were diagnosed before death or discharge. Fifteen patients were treated with simple patching of the ulcer. Perforated ulcers in critically ill patients differ in several important ways from those occurring in otherwise healthy individuals.

Cystadenoma and cystadenocarcinoma of the pancreas.

Cystic neoplasms of the pancreas are uncommon. The authors present one case each of a cystic carcinoma (possibly acinar, which is a rare variant of pancreatic carcinoma), cystadenocarcinoma arising in a mucinous cystadenoma and cystadenoma. These cases illustrate important features of the natural history and management of these lesions. The macrocystic cystadenoma is generally regarded as premalignant and merits aggressive treatment, while the microcystic type is considered benign. If the cystadenoma is removed completely, there should be no recurrence. The cystadenocarcinoma differs from duct carcinoma; usually, the tumour can be removed, and when this is possible the prognosis is excellent. Both the cystadenoma and the cystadenocarcinoma can be mistaken for a pancreatic pseudocyst. The distinction is important.

The rib-pectoralis major osteomyocutaneous flap.

We describe a reliable composite osteomyocutaneous flap used for mandibular reconstruction in 14 patients. The flap is composed of the pectoralis major muscle and the attached fifth or sixth rib, with the overlying skin. This flap is tunneled superiorly under the neck skin. The muscle protects the great vessels. The skin lines the oral cavity or fills an external skin defect, and the rib replaces lost mandible. The rib seems to be adequately vascularized to survive, and does not resorb. Boney union is painless and clinically firm. One flap in the series was lost, and the rib was removed in 3 others. There was 1 persistent fistula.

A new method of oral reconstruction using a free composite foot flap.

We present a series of 10 free composite foot flaps used in 9 patients for floor-of-mouth and mandible reconstruction after composite resection. This one-stage repair replaces the soft tissue as well as the bone that has been resected. The flap is easily obtained from the foot, and is tailored to meet the requirements of the mouth and jaw defect. Donor site morbidity is surprisingly low: two flaps were lost from vascular obstruction, and 1 from delayed infection at ten days. The surviving flaps have provided good cosmetic and functional results. Bony union has occurred in half the grafts, and satisfactory firm fibrous union in the remainder. The flap is also useful for late reconstruction in "oral cripples," and may be used with the skin internally or externally as required. We are pleased with the versatility of this flap in complicated reconstructions.

Use of microvascular flaps including free osteocutaneous flaps in reconstruction after composite resection for radiation-recurrent oral cancer.

Fourteen patients underwent microsurgical free flap procedures for reconstruction after composite resection of radiation-recurrent oral cancer. The use of attached metatarsal bone in nine patients for mandibular reconstruction is in our view a significant advance in this field. Two failures occurred, one due to sepsis and one to delayed thrombosis. Our experience indicates that this procedure deserves a place in the surgical treatment of patients afflicted with oral malignancy.

Naturally occurring immunosuppressive agents. II. The ability of cell-free liver extracts to modify the rejection of allogeneic skin grafts in the rabbit.

It has been demonstrated that cell-free extracts of pig, rabbit and human liver, but not of other parenchymal organs, contain a factor or factors capable of suppressing the proliferative responses of allogeneic and xenogeneic lymphoid cells stimulated with PHA, PWM, Con-A and allogeneic lymphocytes. Intravenous injection of the liver extract is capable of modifying significantly the skin allograft rejection reaction in normal adult outbred rabbits. Work is now in progress to isolate this factor and to determine its composition.

Naturally occurring immunosuppressive agents. I. The presence in normal pig liver of a factor possessing immunosuppressive properties with respect to pig lymphoid cells in vitro.

Saline cell-free extracts of normal pig liver, but not normal pig spleen, contain a noncytotoxic factor (or factors) capable of suppressing the blastogenic response of pig lymphocytes to stimulation with a number of plant mitogens: phytohemagglutinin, pokeweed, and concanavalin A. This reaction is generally considered to be a reflection of the capacity of the cell to participate in an immune reaction. Normal pig serum does not display inhibitory activity. The liver extract must be in contact with the lymphocytes for at least the final 48 hr of the 72-hr culture period in order to suppress the blastogenic response. Whether this active constituent in normal pig liver extract is an immunosuppressive agent in vivo remains to be determined.

Orthotopic liver transplantation utilizing a vascular stapling instrument.

A technique of orthotopic liver transplantation in the pig is described in which the main feature is the accomplishment of four of the five anastomoses by the use of the Vogelfanger NRC vascular suturing instrument. The advantage of this instrument is the rapid accomplishment of safe leak-proof anastomoses.