Cervical screening in detecting and preventing CIN and Cervical Cancer
Table I presents the frequency of screening modalities in women of different age groups. Out of the 214 recorded participants, 72.43% (155) and 27.57% (59) were respectively HIV negative and HIV positive women. Colposcopy was confirmed to be the predominant method (66%) of all cases, followed by PAP (44%) which particularly scored higher in routine screening (21.3%). Colposcopy was indicated in about 11% of cases respectively for a follow-up and/or repeat, followed by biopsy with 8% and PAP indicated less popular (0.5%). VIA (5%) and Colposcopy (0.9%) were popular in women who were screened for the first time (6% of the study population). PAP and biopsy were equally performed in women who were given the opportunity to be screened through outreach screening programmes by the Cancer Association of Namibia in collaboration with Windhoek Central Hospital and Katutura Hospital, with VIA and colposcopy scoring least popular in these programmes.
Screening Associations in women
Screening-related data in Table II revealed that most LSILs were identified by biopsy; subsequently most CIN I lesions were identified by colposcopy. Colposcopy also detected majority of HSILs, followed by biopsy then PAP. Biopsy was established to be the only screening modality which detected and reported 3 cases with CIS. Additionally, infection (HPV, B. vaginosis, Candida spp., Chlamydia spp. And T. vaginalis) and cervicitis were equally detected by biopsy.
Biopsy also detected most cases with invasion or SCC or suggestion thereof. Suggested invasion or SCC or detected invasion or SCC was equally detected by colposcopy.
Screening outcomes - Initial and Final Diagnosis
Table III (a,b) illustrates the screening outcomes at initial screening and final screening as documented in hospital records.
Combined screening by PAP and colposcopy detected most HSILs followed by triage screening (PAP, biopsy and colposcopy) which detected most LSILs in women (HIV-negative) (Table III a).
In Table III (b), combined screening by VIA and colposcopy detected most LSILs; and triage screening by PAP, biopsy and colposcopy detected most HSILs in women who are HIV-positive. Most cases suspected of cancer, invasive cancer, squamous cell carcinoma or carcinoma in situ were observed upon initial diagnosis in HIV-positive women screened by various modalities. Although these cases were observed two-fold upon final diagnosis in women who are HIV-negative.
Screening Heterogeneity
Observations from Table IV (a) revealed that women aged 30-49 reported the highest parity compared to women younger and older than them, as well as sexual partners. Parity was lower in women 29 years old and younger, followed by women aged 50 and older; similarly, sexual partners reported by these women were also lower. Women who had no children scored the lowest, followed by women who reported a parity of 1. Furthermore, women in all age populations reported to have at least one sexual partner. Most women reported more than 4 sexual partners.
As with parity and sexual partners in women aged 30-49, most screening were also reported for women in this age range. In particular, single screening modalities in women 40-49 years old scored equal with parity and sexual partners. Data for women aged 30-39 revealed a similar score for parity and screening. Data for women aged 21 or younger scored equal across parity and sexual partners; whereas data for women aged 22-29 scored similar in parity and sexual partners. Women aged 50 or older scored similar for parity, sexual partners and screening.
The T-test (two-tailed distribution and unequal variance due to different means) and the Chi-squared test statistically assessed screening heterogeneity as well as compared case variables and characteristics between cases.
The data and results for parity (M = 3, SD = 1.63) and sexual partners (M = 2.19, SD = 1.15) indicate that case variables are similar, t(154) = 0.173, p = .8632586. In addition, a chi-square test of independence determined the relation between women of different ages and their characteristics (smoking, co-morbidities, sexual barriers, single and married). The relation between these variables was significant, χ2 (20, N = 155) = 118.7, p = < .00001. Subject characteristics are able to distinguish between these cases and associated lifestyle i.e. smoking, infections, use of contraceptives and their marital status.
Observations from Table IV (b) revealed HIV-positive women aged 30-49 reported the highest parity compared to women younger and older than them, as well as sexual partners. Parity was lower in women 29 years old and younger, followed by women aged 50 and older; similarly, sexual partners reported by these women were also lower. Women who had no children scored the lowest, followed by women who reported a parity of 1 to 2. The frequency of women who reported a parity of 3 and 4 was equal. Furthermore, women aged between 30-49 all reported to have sexual partners (Table IV a, b). Most women reported 3 sexual partners, followed by women with more than 4 sexual partners. Women who reported 4 sexual partners scored the lowest, followed by women with 2 partners. Cases also revealed women with one sexual partner were more likely to also just have one child, as these two associations scored equal. As with parity and sexual partners in women aged 30-49, most screening were also reported for women in this age range. In particular, data for women 40-49 years old scored equal for parity and sexual partners, and similar for screening. Data for women aged 30-39 revealed a similar score for parity and screening. Data for women aged 21 or younger scored equal across parity, sexual partners, and screening; whereas data for women aged 22-29 scored equal in parity and screening, and similar for sexual partners. Women aged 50 or older scored similar for parity and screening. The T-test (two-tailed distribution and unequal variance due to different means) and the Chi-squared test was used to statistically assess screening heterogeneity as well as compare case variables and characteristics between cases of women with HIV. The data and results for parity (M = 2.12, SD = 1.9) and sexual partners (M = 1.56, SD = 1.3) indicate that variables between cases are parallel, t(58) = 0.38, p = .7053334. In addition, a chi-square test of independence was performed to examine the relation between HIV-positive women of different ages and their characteristics (smoking, co-morbidities, sexual barriers, single and married). The relation between these variables were significant, χ2 (4, N = 59) = 128.59, p = < .00001. Subject characteristics in women with HIV were able to distinguish between cases and associated lifestyle i.e. smoking, co-morbidity (i.e. Peripheral vascular disease), use of contraceptives and their marital status.
Outcomes associated with screening and treatment
Pearson test in addition to multivariate analysis determined main outcomes associated with various screening modalities (as depicted in figure 1, 2 and 3)). In single screening, it was confirmed that early precancerous lesions (CIN I) were detected in 7 of the 155 women (4.5%); 18 women developed CIN II (11.6%); and 16 women presented with CIN III or HSIL (10%). Additionally, invasion, SCC, CIS or cancer was suggested in 5 women (3%) as seen in figure 1. For combined screening, CIN I (and LSIL) were observed in 28 women (18%); whereas CIN II was confirmed in 19 women (12%); and CIN III (and HSIL) also presented in 19 women (12%). Moreover, invasion, SCC and CIS (figure 2) were suggested in 2 women (1.3%) who were screened by combined modality. Triage screening observed in 10 women with CIN I or LSIL (6.5%), 7 women with CIN II (4.5%), and 8 women with CIN III or HSIL (5%). Triage screening also identified 3 cases suggesting SCC or cancer (figure 3). Multivariate analysis significantly discriminated single screening in figure 1 by punctuations and/or mosaicism (p = .0498); and combined screening by ASCUS (p = .0498), ASCUS-L (p = .032) and thermal coagulation or cryotherapy (p = .0498). Similarly, in all three different screening modalities (figure 1, 2 and 3), suggested (or confirmed) invasion or invasive SCC or SCC (p = .032 - .0498); and treatment by cone biopsy (p = .032 - .0498) were jointly significant. Subsequently, treatment by LEEP/LOOP (p = .032 - .0498) were conjointly significant in combined (figure 2) and triage screening (figure 3). Irregular (or abnormal) epithelium (p = .0192 - .0498) and invasive cancer (or cancer) (p = .032 - .0498) were jointly significant in single (figure 1) and triage screening (figure 3). Numerous dissimilarities exist between women who developed HSIL or suggested invasion, SCC, CIS or cancer and women who did not. However, reference to Pearson’s and Chi-square in addition to multivariate analysis, variables that significantly associated with invasion (SCC, CIS, or Ca) was having a HSIL, CIN II or CIN III result for Pap and for biopsy or colposcopy result (odds ratio = 0.07; 95% CI =0.0005-7.4091).