Transanal endoscopic microsurgery for excision of rectal lesions: technique and initial results

The aim of this study was to review experience with transanal endoscopic microsurgery (TEM) and to assess its applicability to an existing practice of colorectal surgeons. Patients undergoing TEM excision of rectal lesions from March 1997 through May 1999 were selected for this study. Medical records were reviewed retrospectively to obtain pertinent data, including indications for TEM, tumor size, distance from anal verge, duration of operation, completeness of tumor resection, postoperative complications, duration of stay and follow-up, and recurrence. Thirty-one patients underwent TEM during the 2-year period. Indications for TEM included benign disease in eight patients and cancer in 23 patients. Mean distance of the tumor from the anal verge was 8.3 cm. Mean size of the lesion was 2.8 cm, and mean specimen size was 4.5 cm. Larger specimen sizes allowed for tumors to be removed with negative margins (97%) in all cases but one. Mean duration of operation was 140 minutes (including set-up time), and mean duration of hospital stay was 1.2 days. Major postoperative complications occurred in one patient. Mean duration of follow-up was 15 months, and recurrence developed in two patients during this period. Transanal endoscopic microsurgery excision of rectal lesions with negative margins was possible in 97% of cases with minimal morbidity and a short-duration hospital stay. Follow-up was too brief to evaluate recurrence, but the thoroughness of resection of tumor in a high proportion of cases is promising.

Hyperplastic polyps: "more than meets the eye"? Report of sixteen cases

The vast majority of hyperplastic polyps are small, left-sided, and inconsequential in nature. However, hyperplastic polyps that are large, right-sided, mixed, and found in association with a family history of carcinoma may represent an "atypical" group, and their clinical significance is uncertain. We believe that these atypical lesions should not be lumped together with the common variety of diminutive hyperplastic polyps. Rather, when such hyperplastic polyps are encountered, they should be excised and the patient should be placed on regular colonoscopic surveillance.

Comments on the epidemiology, pathogenesis and control of dengue

Dengue is currently the most important viral disease transmitted to man by arthropods, whether measured by the number of cases or number of deaths. Prevalence of the disease is highest in tropical Asia, intermediate in tropical America, and lowest in tropical Africa. Four distinct dengue viruses have been identified. Types 2 and 3 appear to be more pathogenic on the average than types 1 and 4, but all four can cause severe or fatal dengue syndromes. Infection with any of the four viruses confers life-long homotypic, but not heterotypic, immunity. Dengue viruses can be transmitted by several mosquito species of the genus Aedes, but by far the most common vector is Aedes aegypti. All non-human primates that have been tested are susceptible to infection, but none exhibit signs of illness. The resulting lack of a suitable experimental host other than man has slowed progress in understanding the pathogenesis of severe forms of the disease. Controversy continues over the hypothesis that a first dengue infection increases the risk of severe disease upon re-infection as well as over the principal sites of replication. With regard to replication sites, some authors have mentioned cells of the mononuclear phagocyte lineage while others have implicated hepatocytes. No vaccine is currently available for dengue. Because the principal mosquito vector can use a wide variety of small domestic containers, vector control programs have not been highly effective.

Antiangiogenic strategies and agents in clinical trials

The understanding that the growth of tumors depends on the acquisition of a blood supply has led to the development of new therapies for cancer and other angiogenic diseases based on inhibition of neovascularization. This review examines the role of angiogenesis in cancer progression and describes various strategies for interfering with this process. The developmental status of angiogenesis inhibitors in human clinical trials is presented, including their proposed mechanisms of action. Standard chemotherapeutic agents and angiogenesis inhibitors are compared, noting that different end points might need to be considered in clinical trials and that drug resistance may be less of a problem with antiangiogenic therapy than with conventional chemotherapy regimens. The suggestion is made that cytotoxic chemotherapy and angiogenesis inhibitors used in combination may produce complementary therapeutic benefits in the treatment of cancer.

Dieulafoy's lesion of the anal canal: a new clinical entity. Report of two cases

Dieulafoy's lesion is an unusual source of massive lower gastrointestinal hemorrhage. It is characterized by severe bleeding from a minute submucosal arteriole that bleeds through a punctate erosion in an otherwise normal mucosa. Although Dieulafoy's lesions were initially described only in the stomach and upper small intestine, they are being identified with increasing frequency in the colon and rectum. To our knowledge, however, Dieulafoy's lesion of the anal canal has not been described previously. We present two patients with Dieulafoy's lesion of the anal canal who presented with sudden onset of massive hemorrhage. The clinicopathologic features of this unusual clinical entity are discussed and suggestions are made for diagnosis and management.

Neoplasia after ureterosigmoidostomy

PURPOSE

The occurrence of neoplasia after ureterosigmoidostomy is well-documented in the literature. Because of its rarity, few general surgeons will gain significant exposure to this entity, and colorectal surgeons are likely to be involved with the care of these patients. The purpose of this article is to apprise colorectal surgeons about the management of neoplasia after ureterosigmoidostomy and to familiarize them with the unique anatomy of the reconstructed pelvis.

METHODS

We performed a MEDLINE search to identify articles on ureterosigmoid tumors. The theories regarding the cause and pathology of these tumors were critically analyzed. A consensus was developed for screening patients with ureterosigmoidostomy and for treatment of neoplasia.

RESULTS

The incidence of carcinoma after ureterosigmoidostomy ranges from 2 to 15 percent. Polyps are more common, and it seems that these tumors also follow the sequence of adenocarcinoma that is seen in the common variety of colorectal neoplasia. Neoplastic changes begin with the interaction of urine and feces and the healing colonic mucosa. Both production of nitrosamines by the action of bacteria on urine and DNA damage caused by reactive oxygen radicals produced by neutrophils at the healing anastomosis have been implicated in the pathogenesis of neoplasia. The latent period between formation of ureterosigmoidostomy and the appearance of carcinoma is between 20 and 26 years. Obstructive urinary symptoms that develop more than two years after ureterosigmoidostomy should be viewed with suspicion. The patient should be investigated with a CT scan and colonoscopy, and a barium enema may be required to delineate the anatomy further. If a benign tumor is encountered during colonoscopy, it may be removed by snare polypectomy. For a malignant tumor the segment of colon with ureteric implants should be excised, along with its lymphatic drainage. Bowel continuity is restored primarily, and the ureters are implanted in an ileal conduit.

CONCLUSIONS

Patients with ureterosigmoidostomy should be followed closely for the rest of their lives. The aim of screening is to identify and treat neoplasia before malignancy develops. Furthermore, early detection of neoplasia by close screening will improve survival. Although urine cytology and occult blood are inexpensive tests, colonoscopy remains the criterion standard for follow-up of these patients. Annual colonoscopic surveillance should be started soon after the ureterosigmoidostomy but not later than five to six years after the procedure. Patients who are noncompliant with the vigorous follow-up schedule should be offered the option of resection of the colonic segment at risk with urinary diversion.

Usefulness of a state-legislated, comparative database to evaluate quality in colorectal surgery

PURPOSE

Colorectal surgery, a high-volume procedure, has been targeted for performance improvement to reduce length of stay. Specific postoperative quality indicators and readmission rates should be analyzed concomitantly to assure that adverse events are not associated with earlier discharge.

METHODS

From July 1, 1990, to June 30, 1997, 1,218 consecutive patients who underwent transabdominal colorectal surgery were analyzed for length of stay, mortality, morbidity, and discharge disposition. Each patient was assigned an Admission Severity Group rating 0 to 4 using a hospital-based state-legislated software system (Atlas) to validate comparative performance internally and externally. Readmission data within 120 days of discharge were available for the last 678 consecutive patients from July 1, 1993, to June 30, 1997, using Lastword (computerized medical records).

RESULTS

The annual frequencies of the 1,218 procedures were 173, 183, 175, 146, 167, 189, and 185, respectively, from July 1990 through June 1997. Severity distribution was 32 for Admission Severity Group 0, 517 for Admission Severity Group 1, 540 for Admission Severity Group 2, 128 for Admission Severity Group 3, and 1 for Admission Severity Group 4, with no annual difference (P = 0.012). There was a significant reduction in total length of stay of 3.1 (12.9-9.8) days during the seven years (P = 0.001). The overall operative mortality rate was 1.4 percent, and the morbidity was 2.6 percent, with no annual differences (P = 0.655 and P = 0.033, respectively). The disposition to home did not change (P = 0.21). Of the 678 patients followed up for readmission, 100 (14.7 percent) were readmitted within 120 days, with no annual difference (P = ().302).

CONCLUSION

Mortality, morbidity, disposition, and readmission rates were not affected by a decreased length of stay after colorectal surgery.

Detection of dengue virus RNA by reverse transcription-polymerase chain reaction in the liver and lymphoid organs but not in the brain in fatal human infection

Autopsy tissues from 18 children believed to have died of dengue hemorrhagic fever were tested for the presence of dengue virus RNA by reverse transcription-polymerase chain reaction (RT-PCR). Such RNA was found in 14 of 18 liver specimens, 13 of 18 spleen specimens and 7 of 16 mesenteric lymph node specimens. No dengue virus RNA was detected in 44 samples of brain tissue from 15 individuals, 1 or more of whose other tissues yielded such RNA. All tissues had been tested previously for dengue virus by mosquito inoculation. In those tests, virus was recovered from 5 of 18 liver and 2 of 18 spleen specimens. Thus, the RT-PCR is more sensitive than the most sensitive virus isolation technique for detecting dengue virus or its components in human tissue. Failure to isolate virus from most of spleen and all mesenteric lymph node specimens may indicate that those tissues contained primarily degraded virus undergoing inactivation.

Colorectal cancer after surveillance colonoscopy: false-negative examination or fast growth?

PURPOSE

Colonoscopy is the preferred method for colorectal cancer surveillance of high-risk patients. Despite its high sensitivity, polyps or cancers may be undetected by colonoscopy and later attributed to an accelerated adenoma-carcinoma sequence. This study assesses how the characteristics of colorectal cancers found at intervals between surveillance relate to the adenoma-carcinoma sequence and its prevention.

METHODS

The records of 557 patients with colorectal cancer that were diagnosed from January 1, 1990, to December 31, 1996, were reviewed to identify those patients who had prior colonoscopic surveillance within 60 months of their diagnosis.

RESULTS

There were 29 (5.2 percent) patients who had one or more colonoscopies before diagnosis of their colorectal cancer. Mean interval between diagnosis and prior colonoscopy was 23 (range, 4-59) months. The distribution of cancers included nine cecum, two ascending, three hepatic flexure, five transverse, one splenic flexure, three descending, two sigmoid, three rectum, and one anal canal. The mean tumor size was 4.4 cm for the cecum and 2.4 cm for all other locations. There were 7 Tis, 6 T1, 4 T2, and 12 T3 lesions. Six patients with T3 lesions had prior colonoscopies within 24 months of the diagnosis. Three of four patients with lymphatic metastases had tumors in the cecum. Twenty tumors (69 percent) were well or moderately differentiated. Mean follow-up was 41 (range, 7-95) months with two local recurrences and two unrelated deaths.

CONCLUSIONS

Size, differentiation, and stage of colorectal cancer in addition to the interval to diagnosis suggest that the majority of cancers found during surveillance colonoscopy followed prior false-negative examinations. Because cecal landmarks are most constant, prior photographic documentation may help to prove or disprove fast growth of cancers found in the cecum during surveillance colonoscopy.

A non-invasive means to effectively restore normothermia in cold stressed individuals: a preliminary report

The combined application of subatmospheric pressure and heat to a forearm and hand has been previously reported to be an effective method for restoring normothermia in hypothermic postoperative patients. The objective of this study was to determine whether this technique also could be useful for the treatment of accidental hypothermia. Four otherwise healthy cold-stressed soldiers (core temperature <36.0 degrees C) were studied. In all four cases, application of the subatmospheric pressure induced an immediate local distention of the subcutaneous vasculature of the hand and fingers. Tympanic temperature reached a plateau in a normothermic range within 15 min in all subjects. The subjects also noted rapid elimination of shivering and improvement in subjective assessment of thermal comfort. These results are encouraging and warrant further investigation of the technique.

Replication of dengue type 2 virus in Culex quinquefasciatus (Diptera: Culicidae)

We were able to infect Culex quinquefasciatus by the parenteral route with dengue virus type 2. The percentage of mosquitoes infected was dose dependent and we obtained a rate of 45.6% infected Cx. quinquefasciatus when a 10(5.9) MID50 (mosquito infectious dose for 50% of the individuals as measured in Aedes aegypti) of dengue virus type 2 per mosquito was used. Infection was detected by an immunofluorescent assay performed on mosquito head squashes 14 days after infection. The replication of dengue virus in Cx. quinquefasciatus was either at a very low level of magnitude or generated a large number of noninfectious particles since the triturated bodies of infected Cx. quinquefasciatus did not infect Ae. aegypti mosquitoes when inoculated parenterally. We were unable to infect Cx. quinquefasciatus females orally with an artificial meal that infected 100% of Ae. aegypti females. These findings lead us to agree with the consensus that Cx. quinquefasciatus should not be considered a biological vector of dengue viruses.

Simian T-lymphotropic virus type I infection among wild-caught Indonesian pig-tailed macaques (Macaca nemestrina)

Evidence for the presence of simian T-lymphotropic viruses (STLV-I) was identified in live-caught pig-tailed macaques from two locations in southern Sumatra, Indonesia. Of 60 animals tested, 13.3% of the animals showed seroreactivity to HTLV-I/II enzyme-linked immunosorbent assay (ELISA) antigens. Of these, 75% showed indeterminate reactivity and 25% showed positive reactivity to HTLV-I/II Western blot antigens. Polymerase chain reaction (PCR) analysis of 6 of 8 seroreactive monkeys' peripheral blood mononuclear cell (PBMC) DNA showed production of proper size molecular weight product that hybridized specifically to an STLV-I tax gene-specific probe. Phylogenic analyses of tax gene fragment sequences from the PCR products of two samples, 930287 and 930306, indicated that these animals were infected with retroviruses related to those of the Asian STLV-I clade.

Amalgam alternatives-microleakage evaluation of clinical procedures. Part II: direct/indirect composite inlay systems

This study investigated the degree of dye penetration of two composite inlay systems with different adhesive and bonding protocol. Forty whole extracted premolars and molars were collected. The teeth were immediately stored in water at room temperature. Class II cavity preparations were prepared and restored both, in the direct and the indirect techniques (Coltene Brilliant) and (Kulzer Estilux posterior CVS). The inlays were cemented with a composite luting cement (ART-Bond) and (Kulzer, Adhesive cement). Specimens were subjected to 750 cycles of thermal stress. They were than immersed in 2% Basic fuchsin dye. The teeth were sectioned in three planes before being ranked as to the amount of dye penetration. The data were analysed by the Wilcoxon's rank test at the 95% confidence level. There was no statistically significant difference between the direct and indirect technique considered separately for each composite inlay material, at the cervical margin location. The fuchsin staining in the occlusal area was limited to the enamel in all groups. By using the composite inlay, the factor of adaptation and bonding of composites to dentine become the significant factor contributing to leakage.

Surgical adjuvant active specific immunotherapy for patients with stage III melanoma: the final analysis of data from a phase III, randomized, double-blind, multicenter vaccinia melanoma oncolysate trial

BACKGROUND

A phase III, randomized, double-blind, multicenter trial of active specific immunotherapy (ASI) using vaccinia melanoma oncolysate (VMO) was performed in patients with stage III (American Joint Commission on Cancer) melanoma to determine the efficacy of VMO to increase the disease-free interval (DFI) or overall survival (OS) in these patients. Two interim analyses of data from this trial were performed in May 1994 and June 1995. Although the results from these analyses showed no statistically significant improvement in DFI or OS in all patients using VMO, two subsets-men aged 44-57 years with one to five positive nodes and all patients with clinical stage I and pathologic stage II disease-showed an overall survival advantage with VMO therapy. A final analysis of data from this trial was performed in May 1996 and is reported here. The design of future melanoma vaccine trials is discussed based on information learned from this first randomized, multicenter trial of ASI therapy.

STUDY DESIGN

A polyvalent VMO was prepared using melanoma cells derived from four melanoma cell lines and vaccinia vaccine virus (V). Patients were accrued from 11 United States institutions and were randomized by the Statistical Center at the University of Alabama, Birmingham. Two hundred fifty patients were randomized to treatment with either VMO (1 U containing 2 mg of total protein derived from 5 x 10(6) melanoma cells and 10(5.6) 50% tissue culture infectious dose of vaccinia virus) or control V (1 U containing 10(5.4) 50% tissue culture infectious dose of vaccinia virus) once a week for 13 weeks and then once every 2 weeks for a total of 12 months, or until recurrence. Patient data were collected by the Statistical Center and analyzed as of May 1996 for DFI and OS using Wilcoxon test and log-rank analysis.

RESULTS

Two hundred seventeen patients were found to be eligible according to the inclusion criteria. Data from these patients were analyzed for DFI and OS after a median followup of 46.3 months (50.2 months for VMO and 41.3 months for V). This final analysis showed no statistically significant increase in either DFI (p = 0.61) or OS (p = 0.79) of patients treated with VMO (n = 104) compared with V (n = 113). At 2-, 3-, and 5-year intervals, 47.8%, 43.8%, and 41.7% of patients treated with VMO were disease-free, respectively, compared with 51.2%, 44.8%, and 40.4% of patients treated with V. At the same intervals, 70.0%, 60.0%, and 48.6% of patients treated with VMO survived, compared with 65.4%, 55.6%, and 48.2% of patients treated with V. In a retrospective subset analysis, male patients aged 44-57 years (n = 20) with one to five positive nodes showed 18.9%, 26.82%, and 21.3% improvement in survival at 2-, 3-, and 5-year intervals, respectively, after treatment with VMO when compared with V (n = 18) (p = 0.046).

CONCLUSIONS

This study was a randomized, multicenter, placebo-controlled evaluation of an active specific immunotherapeutic agent to increase the DFI or OS of patients with stage III melanoma in a surgical adjuvant setting. In this trial, ASI with VMO when compared with V showed no difference in either DFI or OS. In a retrospective subset analysis, however, a subset of men with one to five positive nodes, between the ages of 44 and 57 years, showed a survival advantage with VMO. This result suggests that one must include a detailed subset analysis in the design of future trials of ASI for patients with American Joint Commission on Cancer stage III melanoma. An appropriate control arm also must be included in ASI trials.

Pregnancy planning and the impact on work climate, psychological well-being, and work effort in the military

This study examined the joint effects of demographics and pregnancy planning and timing on work climate, psychological well-being, and work effort among 345 pregnant U.S. military women from the Army, Navy, Air Force, and Marines. Rank predicted both pregnancy planning and career timing. Pregnancy planning was positively associated with support from coworkers and supervisors and with enhanced work effort and psychological well-being. Pregnancy timing was positively associated with support from supervisors, reduced harassment, and increased psychological well-being. Rank interacted with the planning and timing measures. Junior officers and enlisted participants reported reduced command and pregnancy support and increased harassment in conjunction with poorly timed pregnancies.

Assessment of first-trimester nuchal translucency by daily reference intervals

Increased fetal nuchal translucency measured in the first trimester is associated with an elevated frequency of chromosomal abnormalities, yet no reference intervals for transvaginal sonographic measurements of fetal nuchal translucency in that period of development have been established. The aim of the present cross-sectional study was to construct appropriate gestational age-specific reference intervals for nuchal translucency. Transvaginal ultrasound was used in 180 normal pregnant women between 9 and 14 weeks of gestation. Reference intervals were constructed by the parametric method. These reference intervals were then compared to the traditional threshold value of 3 mm, when applied to 287 women scheduled for amniocentesis or chorionic villus sampling (CVS). Both methods had the same sensitivity, 85.7%, and negative predictive value, 99.6%, in predicting fetal chromosomal abnormalities. However, the specificity of the gestational age-related reference intervals tended to be higher than that of the 3-mm threshold: 94.6% vs. 87.9%. The positive predictive value of the former method was higher than that of the 3-mm threshold: 28.6% vs. 15%. The increased specificity and positive predictive value of these reference intervals are of particular importance when applied to women under the age of 35 years. In those women, the finding of an abnormally thick nuchal translucency can lead to the performance of amniocentesis or CVS. Therefore, using these reference intervals instead of the traditional 3-mm threshold may save a significant number of unnecessary invasive procedures.

Pregnancy planning and the impact on work climate, psychological well-being, and work effort in the military

This study examined the joint effects of demographics and pregnancy planning and timing on work climate, psychological well-being, and work effort among 345 pregnant U.S. military women from the Army, Navy, Air Force, and Marines. Rank predicted both pregnancy planning and career timing. Pregnancy planning was positively associated with support from coworkers and supervisors and with enhanced work effort and psychological well-being. Pregnancy timing was positively associated with support from supervisors, reduced harassment, and increased psychological well-being. Rank interacted with the planning and timing measures. Junior officers and enlisted participants reported reduced command and pregnancy support and increased harassment in conjunction with poorly timed pregnancies.

Increased survival of patients treated with a vaccinia melanoma oncolysate vaccine: second interim analysis of data from a phase III, multi-institutional trial

OBJECTIVE

The efficacy of vaccinia melanoma oncolysate (VMO) vaccine to increase overall survival and disease-free survival of patients with surgically resected International Union Against Cancer (UICC) stage II melanoma was studied in a phase III, randomized, multi-institutional trial.

SUMMARY BACKGROUND DATA

Phase I and II trials with VMO showed minimal toxicity and clinical efficacy in patients with melanoma. In a recently completed phase III VMO trial, the first interim analysis performed in April 1994 showed an increasing trend in the survival of patients treated with VMO. The second interim analysis was performed in April 1995.

METHODS

Patients with surgically resected stage II (UICC) melanoma were treated with VMO (N = 104) or placebo vaccinia vaccine virus (V) (N = 113) once a week for 13 weeks and then once every 2 weeks for a total of 12 months. Patients' clinical data were collected as of May 1995 and analyzed for survival.

RESULTS

In this second interim analysis, the mean follow-up time is 42.28 months. No survival difference was observed between VMO and V treatments. However, in a retrospective subset analysis, a subset of males between the ages of 44 and 57 years and having one to five positive nodes (at 2-, 3-, and 5-year intervals, 13.6%, 15.9%, and 20.3% difference insurvival in favor of VMO [N = 20] when compared to V [N = 18] [p = 0.037]) and another subset of patients with clinical stage I (at 3- and 5-year intervals, 30% and 7% difference in survival in favor of VMO [N = 20] when compared to V [N = 23], [p = 0.05]) showed significant survival advantage with VMO.

CONCLUSIONS

Although VMO vaccine therapy in surgical adjuvant setting did not produce a significant survival benefit to all patients with melanoma, patients from the above two subsets had significant survival benefit.