HPV types in women with normal cervical cytology.

PCR-based hybridization methods have been used to show that some women with normal cytology are carriers of HPV DNA of the types strongly related to cervical cancer. How these women should be managed remains unclear. This chapter selectively reviews reports which have estimated type-specific HPV prevalence in relation to the presence or absence of morphological signs of HPV infection. Overall, these reports indicate that among women who were identified as carriers of HPV DNA (by PCR-based methods) and who also had a normal cytological smear, the HPV type detected in the majority of instances was a high-risk viral type for cervical cancer (HPV types 16/18 = 44.7%; HPV types 31/33/35 = 8.1%; other and unknown types = 37.9%). This suggests that screening programmes which include PCR-based HPV detection could reduce the false negative rates currently reported by screening programmes based on cytology alone.     

Implementation of human biomonitoring in the Dehcho region of the Northwest Territories,Canada (2016–2017)

Background

Human biomonitoring represents an important tool for health risk assessment, supporting the characterization of contaminant exposure and nutrient status. In communities where country foods (locally harvested foods: land animals, fish, birds, plants) are integrated in the daily diet, as is the case in remote northern regions where food security is a challenge, such foods can potentially be a significant route of contaminant exposure. To assess this issue, a biomonitoring project was implemented among Dene/Métis communities of the Dehcho region of the Northwest Territories, Canada.

Methods

Participants completed dietary surveys (i.e., a food frequency questionnaire and 24-h recall) to estimate food consumption patterns as well as a Health Messages Survey to evaluate the awareness and perception of contaminants and consumption notices. Biological sampling of hair, urine and blood was conducted. Toxic metals (e.g., mercury, lead, cadmium), essential metals (e.g., copper, nickel, zinc), fatty acids, and persistent organic pollutants (POPs) were measured in samples.

Results

The levels of contaminants in blood, hair and urine for the majority of participants were below the available guidance values for mercury, cadmium, lead and uranium. However, from the 279 participants, approximately 2% were invited to provide follow up samples, mainly for elevated mercury level. Also, at the population level, blood lead (GM: 11 μg/L) and blood cadmium (GM: 0.53 μg/L) were slightly above the Canadian Health Measures Survey data. Therefore, although country foods occasionally contain elevated levels of particular contaminants, human exposures to these metals remained similar to those seen in the Canadian general population. In addition, dietary data showed the importance and diversity of country foods across participating communities, with the consumption of an average of 5.1% of total calories from wild-harvested country foods.

Conclusion

This project completed in the Mackenzie Valley of the Northwest Territories fills a data gap across other biomonitoring studies in Canada as it integrates community results, will support stakeholders in the development of public health strategies, and will inform environmental health issue prioritization.

     

Echinococcus vogeli in man, with a review of polycystic hydatid disease in Colombia and neighboring countries

Three cases of polycystic hydatid disease (PHD) from Colombia are reported and 11 others from the region are reviewed. When cysts from two patients were fed to a dog and an ocelot about 250 mature and gravid specimens of Echinococcus vogeli and two poorly developed strobilae, respectively, were recovered. These human cases constitute the first record of the larval stage of E. vogeli, previously known only from the strobilar stage in the type host, the bush dog (Speothos venaticus). Based on the morphological characteristics of the protoscolex rostellar hooks from other PHD cases (6 Colombian, 1 Ecuadorian, and 1 Panamanian), it was concluded that all were also due to E. vogeli, rather than to E. oligarthrus as had been previously suggested. Although E. oligarthrus is or may be present in the same areas, so far no human infection due to this parasite has been confirmed. Of the 14 cases reported, 13 were pathologically proven to be PHD. Clinically, eight had an undiagnosed tumor-like mass in or near the liver, one had a subcutaneous mass in the anterior sixth intercostal space, and in two the cysts were in the chest. Two were autopsy findings. In contrast to E. multilocularis, the cysts produced by E. vogeli were found to be relatively large and filled with fluid; brood capsules and protoscolices were numerous. Focal necrosis was commonly observed but large necrotic cavities were not seen. The main natural intermediate host is the paca (Cuniculus paca); man probably obtains the infection by contamination from feces of infected hunting dogs.     

Treatment of advanced cancer of the cervix with transperineal interstitial irradiation

A pilot study using transperineal interstitial implantation to the parametrium in patients with locally advanced carcinoma of the cervix or with distorted anatomy is presented. Twenty-one consecutive patients (2 cervical stump Stage IB, 3 Stage IIB,15 Stage IIIB, 1 Stage IV,,) received one (12) or two (9) implants following 40–45 Gy whole pelvis external irradiation. In addition 8 patients underwent staging laparotomies concurrently with the first implant procedure. Control of the pelvic tumor was accomplished in 18 of 21 patients (85%) with a mean follow-up of 26 months (range 15 to 48 months). Seven patients (33%) developed long term complications (fistula 3, superficial necrosis of the vagina 1, severe proctitis or cystitis 3). Six of the complications occurred in 8 patients (75 % ) who had radioactive sources placed on the surface of the vaginal obturator as a substitute for the lack of tandem. In contrast, only I in the remaining 13 patients (8%) who did not have obturator sources placed, developed long term complications.     

Bilateral primary germ cell testicular tumors: report of four cases and review of the literature.

Bilateral primary germ cell tumors of the testicle are rare. The last comprehensive review of the literature (1955) revealed a 1.6% incidence. However, during the past twenty years, cases have been reported more often, raising the questions of increased frequency due to prolonged survival following surgery and/or roentgen therapy for unilateral tumors. A search of the medical journals during the past two decades fails to show any increased frequency of bilaterality (1.56%). All general combinations of cell types may occur and the tumors may appear simultaneously or sequentially. Successive seminomas are seen more often followed in frequency by concurrent seminomas. Although 50% of the second primaries were diagnosed within five years, 3% of the patients developed the second tumor after 20 years, stressing the need for extended follow-up. Factors affecting the diagnosis, management and prognosis of bilateral testicular tumors are discussed. Four additional cases of bilateral germ cell tumors are described.     

Interstitial thermoradiotherapy in recurrent gynecologic malignancies

In patients with ovarian carcinoma, the presence of metastatic disease in a retroperitoneal lymph node is indicative of a poor prognosis. Although a “staging laparotomy” is required for proper treatment, definitive information concerning para-aortic and pelvic lymph node metastasis often is not available. To determine the incidence of retroperitoneal lymph node metastases in untreated cases of ovarian carcinoma, a prospective study by selective nodal biopsy was undertaken in 61 unselected patients with the following distribution: Stage I, 11; Stage II, 10; Stage III, 31; and Stage IV, 9. The incidence of para-aortic node metastasis overall was 37.7% and of pelvic node metastasis, 14.8%. Of 23 patients with positive para-aortic nodes, 30.4% had no concomitant pelvic node involvement. Direct relationships between nodal metastasis and clinical stage, tumor grade, and histologic type of tumor were demonstrated. The incidence of positive para-aortic nodes in Stage I disease was 18.2%; in Stage II, 20.0%; in Stage III, 41.9%; and in Stage IV, 66.7%. The corresponding incidence of pelvic node metastasis was 9.1% in Stage I, 10.0% in Stage II, 12.9% in Stage III, and 33.3% in Stage IV. Grade 3 tumors were associated most frequently with nodal involvement, with an incidence of positive para-aortic nodes of 52.5% and of positive pelvic nodes of 15.5%. In patients with a serous type of malignancy, the frequencies of positive para-aortic/pelvic nodes were 44.4%/16.7%, respectively; in the undifferentiated type, 50.0%/10.0%; in the clear cell type, 25.0%/25.0%; and in the mucinous type, 14.3%/ 14.3%. In this small series, 32 patients (52.5%) had positive retroperitoneal nodal involvement. It is concluded that selective biopsies of the para-aortic and pelvic lymph nodes should be part of any “staging laparotomy” for ovarian carcinoma, and that the true incidence of nodal involvement in these patients awaits further investigation.