Multistate Markov Model to Predict the Prognosis of High-Risk Human Papillomavirus-Related Cervical Lesions

Impact of human papillomavirus types on uterine cervical neoplasia

Human papillomavirus (HPV) is a major cause of cervical cancer. As the natural history of HPV-associated cervical lesions is HPV genotype-dependent, it is important to understand the characteristics of these genotypes and to manage them accordingly. Among high-risk HPVs, HPV16 and 18 are particularly aggressive, together accounting for 70% of HPV genotypes detected in cervical cancer. Other than HPV16 and 18, HPV31, 33, 35, 45, 52, and 58 are also at a high risk of progression to cervical intraepithelial neoplasia (CIN)3 or higher. Recent studies have shown that the natural history of HPV16, 18, 52, and 58, which are frequently detected in Japan, depends on the HPV genotype. For example, HPV16 tends to progress in a stepwise fashion from CIN1 to CIN3, while HPV52 and 58 are more likely to persist in the CIN1 to CIN2 state. Among the high-risk HPVs, HPV18 has some peculiar characteristics different from those of other high-risk HPV types; the detection rate in precancerous lesions is much lower than those of other high-risk HPVs, and it is frequently detected in highly malignant adenocarcinoma and small cell carcinoma. Recent findings demonstrate that HPV18 may be characterized by latent infection and carcinogenesis in stem cell-like cells. In this context, this review outlines the natural history of HPV-infected cervical lesions and the characteristics of each HPV genotype.

Risk stratification of invasive cervical cancer diagnosed after cervical conization

BACKGROUND

Cervical intraepithelial neoplasia (CIN) diagnosis is based on colposcopy-aided histological examination. However, its accuracy in CIN diagnosis is limited. Some invasive cervical cancers (ICCs) are diagnosed after cervical conization. Therefore, risk stratification of undetected ICC is particularly important for the management of patients with CIN. This study aimed to identify the risk factors for undetected ICC. We especially focused on the association of human papillomavirus (HPV) genotypes.

METHODS

We retrospectively reviewed the clinicopathological characteristics (including age, parity, and preoperative diagnosis) and HPV genotypes of 348 patients diagnosed with CIN or adenocarcinoma in situ (AIS) who underwent cervical conization at our hospital between 2008 and 2016. The relationship between preoperative factors, including HPV genotypes and post-conization ICC, was evaluated.

RESULTS

Among the 348 patients, 322, 7, and 19 had preoperative CIN3, CIN2, and AIS, respectively; 181 were nulliparous. The median patient age was 41 (23-83) years. HPV genotyping was performed on 237 patients. Overall, post-conization ICC was detected in 16 patients (4.6%). Multivariate analysis showed that nulliparity and HPV16 positivity were the independent risk factors for post-conization ICC (OR: 6.01, P = 0.0302; OR: 5.26, P = 0.0347, respectively). The combination of HPV16 status and parity improved diagnostic accuracy. Seven of 53 HPV16-positive cases (13%) without childbirth history were diagnosed with post-conization ICC. In contrast, none of the HPV16-negative cases with childbirth history was diagnosed with post-conization ICC.

CONCLUSION

HPV16 positivity and nulliparity were identified as risk factors for undetected ICC. Careful treatment selection and preoperative scrupulous examination are especially important in these cases.

Carcinogenesis and management of human papillomavirus-associated cervical cancer

Approximately 95% of cervical cancer are caused by human papillomavirus (HPV) infection. Although it is estimated that HPV-associated cervical cancer will decrease with the widespread use of HPV vaccine, it may take time for HPV-associated cervical cancer to be eliminated. For the appropriate management of HPV-associated cervical cancer, it is important to understand the detailed mechanisms of cervical cancer development. First, the cellular origin of most cervical cancers is thought to be cells in the squamocolumnar junction (SCJ) of the uterine cervix. Therefore, it is important to understand the characteristics of SCJ for cervical cancer screening and treatment. Second, cervical cancer is caused by high risk HPV (HR-HPV) infection, however, the manner of progression to cervical cancer differs depending on the type of HR-HPV: HPV16 is characterized by a stepwise carcinogenesis, HPV18 is difficult to detect in precancerous lesions, and HPV52, 58 tends to remain in the state of cervical intraepithelial neoplasia (CIN). Third, in addition to the type of HPV, the involvement of the human immune response is also important in the progression and regression of cervical cancer. In this review, we demonstrate the carcinogenesis mechanism of HPV-associated cervical cancer, management of CIN, and the current treatment of CIN and cervical cancer.

Estimating Bidirectional Transitions and Identifying Predictors of Mild Cognitive Impairment

BACKGROUND AND OBJECTIVES

Various resources exist for treating mild cognitive impairment (MCI) or dementia separately as terminal events or for focusing solely on a 1-way path from MCI to dementia without taking into account heterogeneous transitions. Little is known about the trajectory of reversion from MCI to normal cognition (NC) or near-NC and patterns of postreversion, which refers to cognitive trajectories of patients who have reversed from MCI to NC. Our objectives were to (1) quantitatively predict bidirectional transitions of MCI (reversion and progression), (2) explore patterns of future cognitive trajectories for postreversion, and (3) estimate the effects of demographic characteristics, APOE, cognition, daily activity ability, depression, and neuropsychiatric symptoms on transition probabilities.

METHODS

We constructed a retrospective cohort by reviewing patients with an MCI diagnosis at study entry and at least 2 follow-up visits between June 2005 and February 2021. Defining NC or near-NC and MCI as transient states and dementia as an absorbing state, we used continuous-time multistate Markov models to estimate instantaneous transition intensity between states, transition probabilities from one state to another at any given time during follow-up, and hazard ratios of reversion-related variables.

RESULTS

Among 24,220 observations from 6,651 participants, there were 2,729 transitions to dementia and 1,785 reversions. As for postreversion, there were 630 and 73 transitions of progression to MCI and dementia, respectively. The transition intensity of progression to MCI for postreversion was 0.317 (2.48-fold greater than that for MCI progression or reversion). For postreversion participants, the probability of progressing to dementia increased by 2% yearly. Participants who progressed to MCI were likely to reverse again (probability of 40% over 15 years). Age, independence level, APOE, cognition, daily activity ability, depression, and neuropsychiatric symptoms were significant predictors of bidirectional transitions.

DISCUSSION

The nature of bidirectional transitions cannot be ignored in multidimensional MCI research. We found that postreversion participants remained at an increased risk of progression to MCI or dementia over the longer term and experienced recurrent reversions. Our findings may serve as a valuable reference for future research and enable health care professionals to better develop proactive management plans and targeted interventions.

Multistate models for the natural history of cancer progression

BACKGROUND

Multistate models can be effectively used to characterise the natural history of cancer. Inference from such models has previously been useful for setting screening policies.

METHODS

We introduce the basic elements of multistate models and the challenges of applying these models to cancer data. Through simulation studies, we examine (1) the impact of assuming time-homogeneous Markov transition intensities when the intensities depend on the time since entry to the current state (i.e., the process is time-inhomogenous semi-Markov) and (2) the effect on precancer risk estimation when observation times depend on an unmodelled intermediate disease state.

RESULTS

In the settings we examined, we found that misspecifying a time-inhomogenous semi-Markov process as a time-homogeneous Markov process resulted in biased estimates of the mean sojourn times. When screen-detection of the intermediate disease leads to more frequent future screening assessments, there was minimal bias induced compared to when screen-detection of the intermediate disease leads to less frequent screening.

CONCLUSIONS

Multistate models are useful for estimating parameters governing the process dynamics in cancer such as transition rates, sojourn time distributions, and absolute and relative risks. As with most statistical models, to avoid incorrect inference, care should be given to use the appropriate specifications and assumptions.

Natural History of Anal Papillomavirus Infection in HIV-Negative Men Who Have Sex With Men Based on a Markov Model: A 5-Year Prospective Cohort Study

Objective

Men who have sex with men (MSM) are at increased risk for Human papillomavirus (HPV) infection compared to women and heterosexual men. We aimed to assess the incidence, clearance and duration of anal human papillomavirus (HPV) infection in HIV-negative MSM and the influencing factors in a 5-year prospective cohort study.

Methods

From April 2016 to April 2021, HIV-negative MSM were recruited and followed every 6 months in Urumqi, Xinjiang, China. Questionnaires and anal swabs were collected at baseline and every 6 months. We detected 37 anal HPV genotypes using the HPV Geno Array Diagnostic Kit Test. Incidence and clearance rates of anal HPV infection and the influencing factors were estimated using a two-state Markov model.

Results

A total of 585 MSM were included with a median age of 37 years [interquartile range (IQR): 31–43 years] and were followed for a median 2.8 years (IQR: 1.8–3.6 years). Incidence rates for any HPV and high-risk HPV (Hr-HPV) were 53.4 [95% confidence interval (CI): 49.1–58.0] and 39.0 (95% CI: 35.7–42.5)/1,000 person-months. Median duration of infection was 9.67 (95% CI: 8.67–10.86) and 8.51 (95% CI: 7.57–9.50) months, respectively. Clearance rates for any HPV and Hr-HPV were 50.9 (95% CI: 46.7–55.3) and 62.1 (95% CI: 56.8–66.7)/1,000 person-months, respectively. HPV16 and HPV6 had the highest incidence, lowest clearance rate and longest duration of infection among Hr-HPV and low-risk HPV (Lr-HPV) types, respectively. Receptive anal sex is a risk factor for any HPV [hazard ratio (HR) = 1.66, 95% CI: 1.16–2.38] and Hr-HPV infection (HR = 1.99, 95% CI:1.39–2.85). Recent anal sex without condom use was significantly associated with any HPV (HR = 1.80, 95% CI: 1.10–2.94) and Hr-HPV infection (HR = 2.60, 95% CI: 1.42–4.77). Age ≥35 years was significantly associated with Lr-HPV HPV infection only (HR = 1.40, 95% CI: 1.02–1.93). Both inserted and receptive anal sex (HR = 0.60, 95% CI: 0.40–0.89) and anal sex ≥2 times per week (HR = 0.61, 95% CI: 0.43–0.87) were associated with reduced Hr-HPV clearance. Six of the nine-valent vaccine types (HPV6, 11, 16, 18, 52 and 58) occurred most frequently, which indicates the need for high vaccination coverage in MSM.

Conclusions

In this cohort study, high incidence and low clearance of any HPV, Hr-HPV and individual HPV infections emphasize the importance of MSM vaccination. Modifiable behavioral factors such as condoms and drug use should be incorporated into HPV prevention strategies.

Study on Dynamic Progression and Risk Assessment of Metabolic Syndrome Based on Multi-State Markov Model

AIM

Metabolic syndrome (MetS) coexists with the occurrence and even death of cardiovascular disease and diabetes mellitus. It is essential to study the factors in the dynamic progression of MetS in the interest of prevention and control.

PURPOSE

The aim of this study was to analyze the dynamic progression of Mets and explore the potential factors influencing the progression or reversal of MetS.

PATIENTS AND METHODS

This study involved 5581 individuals from two waves of the China Health and Retirement Longitudinal Study: 2011 and 2015. A multistate Markov model containing 4 states (free of metabolic disorder (FMD), mild metabolic disorder (MMD), severe metabolic disorder (SMD) and MetS) was adopted to study the dynamic progression of MetS and its influencing factors.

RESULTS

After follow-up, a total of 2862 cases (50.28% of the total number) had disease state transition. The intensity of transition from MetS to SMD is the same as that from SMD to MMD, and is greater than that from MMD to Mets (0.06 vs 0.05). For the MetS state, a mean of 1/0.08=12.5 years was spent in the MetS state before recovery. The exercise, smoke, drink, BMI level, hyperuricemia had statistically significant effects on progression of MetS status (P<0.05). The obesity or overweight, little exercise, smoke, drink and hyperuricemia increased the risk of forward progression of MetS disease status. There were significant nonmodifiable (age, gender) and modifiable factors (exercise, drink, BMI level, or high HbA1c) associated with reversion of MetS state.

CONCLUSION

The likelihood of progression from MMD to MetS is less likely than that of reversion from MetS to SMD and SMD to MMD. Old females were more resistant to recover from worse states than males. Prevention and intervention measures should be adopted early when MMD or SMD onset occurs.

Prognosis of high-risk human papillomavirus-related cervical lesions: A hidden Markov model analysis of a single-center cohort in Japan

Introduction

Previous studies have shown that individuals with human papillomavirus (HPV)‐related cervical lesions have different prognoses according to the HPV genotype. However, these studies failed to account for possible diagnostic misclassification. In this retrospective cohort study, we aimed to clarify the natural course of cervical lesions according to HPV genotype to account for any diagnostic misclassification.

Materials and Methods

Our cohort included 729 patients classified as having cervical intraepithelial neoplasia (CIN). HPV was genotyped in all patients, who were followed up or treated for cervical lesions at the University of Tokyo Hospital from October 1, 2008 to March 31, 2015. Hidden Markov models were applied to estimate the diagnostic misclassification probabilities of the current diagnostic practice (histology and cytology) and the transitions between true states. We then simulated two‐year transition probabilities between true cervical states according to HPV genotype.

Results

Compared with lesions in patients with other HPV genotypes, lesions in HPV 16‐positive patients were estimated to be more likely to increase in severity (i.e., CIN3/cancer); over 2 years, 17.7% (95% confidence interval [CI], 9.3%–29.3%) and 27.8% (95% CI, 16.6%–43.5%) of those with HPV 16 progressed to CIN3/cancer from the true states of CIN1 and CIN2, respectively, whereas 55%–70% of CIN1/2 patients infected with HPV 52/58 remained in the CIN1/2 category. Misclassification was estimated to occur at a rate of 3%–38% in the current diagnostic practice.

Conclusion

This study contributes robust evidence to current literature on cervical lesion prognosis according to HPV genotype and quantifies the diagnostic misclassification of true cervical lesions.

Genotype-specific Distribution and Change of High-risk Human Papillomavirus Infection and the Association with Cervical Progression Risk in Women with Normal Pathology and Abnormal Cytology in a Population-based Cohort Study in China

Objectives: Women with normal pathology screened from abnormal cervical cytology are a special population with higher progression risk than women with normal cytology. However, the associations between genotype distribution and changes of high-risk human papillomavirus (HR-HPV) infection and cervical progression risk in this special population remain unclear.

Methods: A total of 1232 women with normal pathology screened from abnormal cervical cytology were enrolled into this cohort with 2-year follow-up. HPV genotyping detection was performed through flow-through hybridization. Hazard ratios (HRs) and Odds ratios (ORs) were calculated using Cox proportional hazard regression and logistic regression models, respectively.

Results: Overall HR-HPV prevalence at baseline was 29.0%, with HPV16, 52, 58, 53 and 51 the top five genotypes. The 2-year persistence rate of HR-HPV infection was 31.9%. Compared with HR-HPV negative, the adjusted HRs of overall HR-HPV, HPV16, 31/33, 58, 51, and 53 infections for the progression risk of normal cervix were 5.31, 7.10, 6.95, 5.74, 5.04, and 4.88, respectively. Multiple HR-HPV infection cannot lead to an additional risk of progression relative to single HR-HPV infection. In comparison with HR-HPV persistently negative, same-type HR-HPV persistence was positively associated with progression risk of normal cervix (adjusted OR: 22.26), but different-type HR-HPV persistence was not linked to cervical progression.

Conclusion: Genotypes and persistence of HR-HPV infection could stratify the cervical progression risk in women with normal cervical pathology and abnormal cytology and provide evidence for development of next generation of vaccines. HPV51 and 53 deserved attention apart from HPV16, 31, 33, and 58.