Association Between Insurance Status and Nonelderly Penile Squamous Cell Carcinoma Survivorship: A National Retrospective Analysis

Abstract

Background: Penile squamous cell carcinoma is an aggressive malignancy with significant physical and psychological impacts. Socioeconomic factors influence prognosis in genitourinary cancers, making the investigation of insurance status critical for reducing cancer burden and promoting health equity. Materials and Methods: Men diagnosed with primary penile squamous cell carcinoma from 2007 to 2015 were identified from the Surveillance, Epidemiology, and End Results (SEER) national database. Participants were categorized based on insurance status: privately insured, Medicaid, and uninsured. Pearson’s chi-squared test assessed the distribution of observed frequencies between the patient demographics, socioeconomic status, tumor characteristics, and surgical variables across the insurance groups. Overall and cancer-specific survival was estimated using a multivariate Cox hazards proportional model analysis. Results: The multivariate Cox hazards proportional model showed that, compared to privately insured patients, Medicaid patients had an increased risk for overall death (hazard ratio [HR] = HR 1.54; 95% CI, 1.12–2.07). For cancer-specific mortality, Medicaid patients had an increased risk of death compared to privately insured patients (HR 1.58; 95% CI, 1.11–2.25). Conclusions: Medicaid does not mitigate the differences caused by health insurance status due to health insurance disparities for overall or cancer-specific mortality. Lower Medicaid reimbursements and out-of-pocket costs lead to a narrow network of physicians, hospitals, and treatment modalities that compromise health equity. Increasing awareness of health insurance disparities and improving access to care via a clinician–community–governmental partnership can potentially lead to improved predictive outcomes.

1. Introduction

Penile squamous cell carcinoma, which accounts for 95% of all penile tumors, is an aggressive malignancy associated with early lymphatic spread [1]. The etiology of the neoplasm is multifactorial, with risk factors including phimosis, cigarette smoking, human papillomavirus infection, and chronic balanitis [2]. These factors contribute to carcinogenesis through mechanisms such as DNA damage, chronic inflammation, and impaired immune function, increasing the risk of malignant transformation in penile epithelial cells [3]. The diagnosis of the neoplasm has significant psychological consequences with patients delaying treatment modalities for up to one year [3].

Health disparities in cancer are evident, with minority populations and low-income communities experiencing higher mortality rates and more advanced disease at diagnosis due to reduced access to screening, timely care, and advanced treatments. These gaps are particularly notable in cancers such as prostate, breast, cervical, and colorectal cancer [4]. Patient demographic factors have been linked with a disproportionate incidence of penile cancer and morbidity. For example, advanced penile staging has been associated with lower socioeconomic status [5]. African American penile cancer patients are less likely to undergo surgical management [6]. Lower-volume centers have been correlated with lower utilization of penile-sparing approaches and recommended treatment modalities [7]. These findings reflect the varying cancer burden across social demographic disparities [5]. Understanding the role of health insurance inequalities in penile squamous cell carcinoma is pertinent to maximizing health improvement and reducing cancer disparities [8].

The Affordable Care Act (ACA) was implemented to address health inequalities, especially Medicaid expansion [9]. Research shows that the ACA reduces uninsured rates in vulnerable populations and uncompensated care costs [10]. However, it is unknown whether insurance status can mitigate the socioeconomic effects in penile squamous cell carcinoma patients. With ongoing debates about the value of Medicaid expansion, it is critical to understand the relationship between insurance status and cancer mortality [11,12,13].

This study evaluates the association between squamous cell penile cancer survivorship based on insurance type and status. Evaluating insurance-mediated cancer outcomes has considerable implications for health equity in directing data-driven national health policy reform. We hypothesize that privately insured insurance coverage will have a beneficial impact on overall and cancer-specific mortality among penile squamous cell carcinoma patients.

2. Material and Methods

2.1. Study Design and Data Source

The retrospective analysis utilized data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database [1]. This study was reviewed and determined exempt from The University of Texas Medical Branch’s Institutional Review Board.

2.2. Study Population

Primary penile tumors were identified using the International Classification of Diseases, Third Edition for Oncology (ICD-O-3) site codes: C60.0-Prepuce, C60.1-Glans penis, C60.2-Body of penis, C60.8-Overlapping lesion of penis, and C60.9-Penis, NOS. Squamous cell carcinoma cases were selected using ICD-O-3 morphology codes 8050-8089. The analysis was restricted to patients diagnosed between 2007 and 2015 given that insurance records were not available until 2007. Patients were further limited to individuals < 65 years old since patients 65 and older are eligible for Medicare [2]. Patients whose cause-specific death classification, follow-up dates, race, insurance status, and American Joint Committee on Cancer Staging Manual, 6th ed. tumor node metastasis (TNM) staging were ambiguous were excluded from the study population. In total, 903 penile squamous cell carcinoma patients were identified and grouped based on insurance status: privately insured, Medicaid, and uninsured.

2.3. Covariates

Patient demographics, tumor morphology, treatment, and survival data were extracted for all cases. Demographic variables included age; race (white, black, or other), ethnicity (non-Hispanic or Hispanic); marital status (married, single, divorced/separated/widowed, or unknown); county-level, median household income (quartiles); county-level, % with at least 4 years of college (quartiles); and insurance (privately insured, Medicaid, or uninsured). Tumor characteristics included primary site (prepuce; penis glans; body of penis; overlapping lesion of penis; or penis, not otherwise specified), tumor grade (I, II, III, or IV), TNM status (I–II or III–IV), lymph node involvement (yes or no), and distant metastasis (yes or no). Treatment covariates included chemotherapy (yes or no) and penectomy (yes or no).

2.4. Outcomes Variables

Overall survival (in months) was defined as time to death from any cause. Cancer-specific survival was defined as time to death from penile cancer (ICD-10 C60). For cancer-specific mortality, patients were censored at the end of the study date or non-penile deaths.

2.5. Statistical Analysis

Patients were categorized based on insurance types (privately insured, Medicaid, and uninsured) for analysis. Pearson’s chi-squared test was utilized to determine the distribution of observed frequencies between the patient demographic factors, socioeconomic status, tumor characteristics, and surgical variables across the insurance types [14]. The unadjusted probability of survival was calculated using the Kaplan–Meier method [15]. Multivariate Cox proportional hazard models were performed with the dependent variable being time overall or cancer-specific death [16]. Cox model adjusted for age; race; ethnicity; marital status; county-level, median household income; county-level, % with at least 4 years of college; primary site; grade; TNM stage; node involvement; distant metastasis; penectomy; and chemotherapy. All statistical analyses were conducted using SPSS (Statistical Package for the Social Science) software (version 27).

3. Results

Cohort selection and exclusion criteria are outlined in Figure 1. After the exclusion criteria were applied, there was a total of 903 patients who were diagnosed with penile squamous cell carcinoma from 2007 to 2015. The mean age for the cohort was 53.0 years old (SD 8.95), and the median follow-up time was 38.0 months. In this study, 561 patients (62.1%) were insured with privately insured, 215 patients (23.9%) were insured with Medicaid, and 126 patients (14.0%) were uninsured

3.1. Cohort Characteristics

Pearson’s chi-squared test showed statistical significance between health insurance and the following variables: age (p < 0.001); race (p = 0.011); ethnicity (p < 0.001); marital status (p < 0.001); county-level, median household income (p = 0.010); and primary site (p = 0.005) between the insurance groups. In relation to age, the uninsured group (mean age = 48.29, SD 9.48) was younger when compared to the privately insured (mean age = 54.5, SD 8.45) and Medicaid groups (mean age = 51.9, SD 8.81). In terms of race, white patients represented a greater segment of the privately insured group (85.7%) than the Medicaid (79.6%) and uninsured groups (75.4%). For ethnicity, non-Hispanic patients represented a greater segment of the privately insured patients (76.6%) than the Medicaid (60.2%) and uninsured patients (62.7%). Regarding marital status, the Medicaid group had a lower proportion of married patients (33.8%) compared to the privately insured (62.2%) and uninsured groups (44.4%). Patients living in counties with a median income less than USD 45,230 were more common in the uninsured (34.9%) than the privately insured (25.7%) and Medicaid groups (23.6%). In relationship to primary sites, primary glans neoplasms were more common in the Medicaid group (36.1%) than the privately insured (29.1%) and uninsured groups (20.6%). The baseline characteristics of the cohort are outlined in

Table 1. Characteristics of squamous cell penile cancer patients.

		Insurance Type						Exact Test
		Insured Privately Insured		Any Medicaid		Uninsured
		N	%	N	%	N	%	p
Age	≤50 years old	143	25.5	79	36.6	71	56.3	<0.001
	>50 years old	418	74.5	137	63.4	55	43.7
Race	White	481	85.7	172	79.6	95	75.4	0.011
	Black	48	8.6	32	14.8	23	18.3
	Other *	32	5.7	12	5.6	8	6.3
Ethnicity	Non-Hispanic	430	76.6	130	60.2	79	62.7	<0.001
	Hispanic	131	23.4	86	39.8	47	37.3
Marital status	Married	349	62.2	73	33.8	56	44.4	<0.001
	Single	101	18.0	89	41.2	53	42.1
	D/S/W	78	13.9	43	19.9	11	8.7
	Unknown	33	5.9	11	5.1	6	4.8
County-level, median household income	≤USD 45,230	144	25.7	51	23.6	44	34.9	0.010
	USD 45,230–USD 56,200	173	30.8	88	40.7	40	31.7
	USD 56,200–USD 64,310	94	16.8	34	15.7	23	18.3
	>USD 64,310	150	26.7	43	19.9	19	15.1
County-level, % with at least 4 years of college	≤18.78%	135	24.1	52	24.1	40	31.7	0.052
	18.78–28.8%	148	26.4	58	26.9	22	17.5
	28.8–35.3%	127	22.6	63	29.2	35	27.8
	>35.3%	151	26.9	43	19.9	29	23.0
Primary site	Prepuce	64	11.4	24	11.1	17	13.5	0.005
	Glans penis	163	29.1	78	36.1	26	20.6
	Body of penis	31	5.5	12	5.6	15	11.9
	Overlapping lesion of penis	15	2.7	7	3.2	9	7.1
	Penis, NOS	288	51.3	95	44.0	59	46.8
Grade	Grade 1	151	26.9	62	28.7	32	25.4	0.106
	Grade 2	259	46.2	99	45.8	51	40.5
	Grade 3	76	13.5	32	14.8	32	25.4
	Grade 4	3	0.5	1	0.5	0	0.0
	Unknown	72	12.8	22	10.2	11	8.7
TNM stage	I–II	413	73.6	136	63.0	79	62.7	0.390
	III–IV	148	26.4	80	37.0	47	37.3
Node involvement	Yes	128	22.8	63	29.2	33	26.2	0.172
	No	433	77.2	153	70.8	93	73.8
Distant metastasis	Yes	19	3.4	14	6.5	4	3.2	0.128
	No	542	96.6	202	93.5	122	96.8
Penectomy	Yes	325	57.9	143	66.2	77	61.1	0.106
	No	236	42.1	73	33.8	49	38.9
Chemotherapy	Yes	86	15.3	40	18.5	26	20.6	0.266
	No	475	84.7	176	81.5	100	79.4

Abbreviations: D/S/W, divorced/separated/widowed; NOS, not otherwise specified. * Other race/ethnicity includes American Indian/Alaska native and Asian/Pacific Islander.

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3.2. Survival Analysis

Overall (p < 0.001) and cancer-specific survival (p < 0.001) were significantly different between insurance type via a univariate Kaplan–Meier curve log rank test. The overall survival (p < 0.001) for the privately insured patients (mean survival time = 90.98 months; SE = 1.98; 95% CI, 87.10–94.86) was significantly higher than the Medicaid patients (mean survival time = 69.46 months; SE = 3.83; 95% CI, 61.95–76.96) and uninsured patients (mean survival time = 78.72 months; SE = 4.90; 95% CI, 69.12–88.32). The cancer-specific survival (p < 0.001) for the privately insured patients (mean survival time = 98.12 months; SE = 1.81; 95% CI, 94.57–101.67) was significantly higher than the Medicaid patients (mean survival time = 79.05 months; SE = 3.85; 95% CI, 71.50–86.61) and uninsured patients (mean survival time = 87.51 months; SE = 4.73; 95% CI, 78.24–96.77). Results from the Kaplan–Meier log-rank test based on insurance types are depicted in

Table 2. Kaplan–Meier analysis for overall and cause-specific survival rates based on insurance.

Insurance Type	Overall Survival (Months)				Cause-Specific Survival (Months)
	Mean	SE	95% CI		Mean	SE	95% CI
Privately insured	90.98	1.98	87.10	94.86	98.12	1.81	94.57	101.67
Medicaid	69.46	3.83	61.95	76.96	79.05	3.85	71.50	86.61
Uninsured	78.72	4.90	69.12	88.32	87.51	4.73	78.24	96.77
Overall	84.98	1.69	81.66	88.29	92.97	1.590	89.86	96.08

Abbreviations: SE, standard error; CI, confidence interval.

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Results from the multivariate Cox proportional hazard regression model (

Table 3. Multivariate Cox proportional hazards regression analysis based off insurance type.

	Insurance Type	Overall Survival (Months)		Cause-Specific Survival (Months)
		HR (95% CI)	p-Value	HR (95% CI)	p-Value
Adjusted Mortality Risk	Privately insured	Ref		Ref
	Medicaid	1.54 (1.12–2.07)	0.005	1.58 (1.11–2.25)	0.011
	Uninsured	1.22 (0.89–1.80)	0.314	1.15 (0.73–1.80)	0.558

Abbreviations: HR, Hazard Ratio; CI, Confidence Interval. The multivariate Cox regression models adjusted for the following variables: age; race; ethnicity; marital status; county-level, median household income; county-level, % with at least 4 years of college; primary site; grade; node involvement; distant metastasis; penectomy; and chemotherapy.

) show that after adjusting for age; race; ethnicity; marital status; county-level, median household income; county-level, % with at least 4 years of college; primary site; grade; TNM stage; node involvement; distant metastasis; penectomy; and chemotherapy, overall mortality was significantly higher for Medicaid patients (HR 1.54; 95% CI, 1.12–2.07; p = 0.005) when compared to the privately insured reference group. In addition, cancer-specific mortality was significantly higher for Medicaid patients (HR 1.58; 95% CI, 1.11–2.25; p = 0.011) when compared to the privately insured reference group. Results from the multivariate Cox proportional hazard regression analyses based on insurance type are depicted in Table 3.

4. Discussion

By using data from a national population-based registry, we evaluated the association between insurance status and survival outcomes in 903 patients with penile squamous cell carcinoma. Our analysis showed that having Medicaid coverage does not mitigate the differences attributed to socioeconomic factors for overall or cancer-specific mortality. While previous penile studies have shown cancer prognostic disparities regarding socioeconomic factors, to the best of the author’s knowledge, this is the first to evaluate the interaction between health insurance and penile cancer. Our findings fill a significant vacuum in the literature as the first study to assess the effect of health insurance status on survival outcomes in penile squamous cell carcinoma. They also offer insights not before investigated in similar uncommon cancers.

Our findings are concordant with prior research examining the impact of Medicaid on prognostic outcomes in genitourinary sites. Lu-Yao et al. reported that, among prostate cancer patients, Medicaid experienced a 103% and 61% increase in overall and prostate cause-specific mortality, respectively [17]. For muscle-invasive bladder cancer, Fletcher et al. found that Medicaid patients were more likely to die of bladder cancer than those with private insurance [11]. In addition, Stone et al. reported that private insurance is associated with improved overall survival in primary urethral cancer patients [18]. These findings highlight a persistent gap in health equity in the underinsured population.

Given our results, Medicaid patients’ access to providers and treatments needs to be assessed to address Medicaid health insurance disparities. One potential explanation for this disparity could be the limited access to high-quality care that Medicaid patients often face. Medicaid users are sometimes limited to smaller provider networks, which may prevent them from accessing high-volume clinics proven to produce superior results, skilled specialists, and cutting-edge cancer treatments. Disparities may also be exacerbated by variations in Medicaid physician participation. According to studies, because Medicaid has lower reimbursement rates and more administrative responsibilities, many doctors—especially those in specialized fields—may restrict the number of Medicaid patients they take on [19]. Moreover, factors underlying the refusal are lower reimbursement rates and higher administrative burdens associated with Medicaid [5,6]. Moreover, Medicaid patients require more attention than that of privately insured patients. Medicaid patients are more likely to present with a disability, comorbidity, obesity, and transportation barriers that consume provider resources and hinder care. This leads to increased postoperative care recommendations and discharge planning with little incentive for physicians [20]. In addition, Medicaid coverage is not binary but coupled with out-of-pocket costs, which include higher premiums, deductibles, and coinsurance [21]. Individuals cope with these financial burdens by delaying tests, treatments, and preventative care [21,22]. Cost sharing can render health care unaffordable thus limiting health care access [21].

Medicaid patients may have insurance coverage but their access is limited to a narrow spectrum of physicians, hospitals, and treatments [7]. Medicaid coverage failing to meet patients’ need for complex care has wide-ranging implications [1]. Limited access to care induces socioeconomic and psychological effects thus discouraging patients from self-managing their health and seeking treatment [6]. Various studies have shown that patients with limited access to care are more likely to present with advanced genitourinary cancers [23]. Limited access to care, delay in diagnosis, and advanced staging all contribute to worse overall and penile-cause-specific mortality.

Interestingly, the present study’s results regarding the uninsured diverge from prior findings. Adjusting for patient demographics, socioeconomic status, tumor characteristics, and treatment variables eliminated the mortality disadvantage in the uninsured group. The reasoning behind the lack of survival disadvantage is unclear. One possible explanation is that once uninsured patients access care, they receive similar quality of care as privately insured patients, while Medicaid receives inferior quality of care and limited access to specialists [24]. Another possible reason is that given the uninsured sample size, a low statistical power reduced the chance of detecting the true effect. Furthermore, this finding might result from survival bias, which holds that only healthier uninsured patients make it to the point of diagnosis. Lastly, uninsured people may wait until their symptoms are severe before seeking care, meaning they will receive similar care whenever they do.

Clinical implications for the results of this study include strategies to identify health insurance disparities to eliminate barriers to access to care for underinsured and uninsured populations. Clinicians can take the initiative by asking patients about social challenges in a culturally sensitive way. Then, integrating information about socioeconomic factors into medical records allows the medical team to take these factors into account [25]. Social prescribing by health care workers will connect patients with various governmental and community resources to help build patients’ resilience. Engaging community resources and local governments is needed to face the challenges that have become social norms [24].

While this study highlights challenges such as lower reimbursements and administrative burdens that impact Medicaid patients’ access to care, it is also important to consider the evolving role of Medicaid, particularly following the ACA’s Medicaid expansion [26]. The ACA significantly increased Medicaid enrollment, aiming to reduce uninsured rates and enhance access to primary and preventive care. However, disparities persist, especially in non-expansion states, and Medicaid patients often face limited access to specialized care due to narrower provider networks and lower provider participation rates. To address these gaps, policy changes could include increasing Medicaid reimbursement rates to attract more providers, reducing administrative burdens to facilitate patient care, and expanding access.

Our study has a broad impact on clinical and national guidelines. Awareness of socioeconomic factors and health insurance disparities can lead to better prognostic assessments by providers. Thus, care can be individualized to insurance status to reduce cancer burden and health inequality. Since the passage of the Affordable Care Act, progress has taken place to expand insurance coverage to nonelderly patients. By revealing disparities in cancer outcomes, our findings can influence future health care policies. Clinically, this finding implies that improved care coordination and support services, such as patient navigators, may help Medicaid patients fill in access gaps to specialty treatments. Furthermore, the similar survival outcomes between uninsured and non-Medicaid patients show that once uninsured patients receive care, the quality of that care may be comparable to that of non-Medicaid patients. This suggests that timely access—rather than just the type of insurance—may be a key factor in survival outcomes. Our study warrants a more comprehensive evaluation of clinical–community–governmental partnerships to ameliorate prognostic disparities and expand access to care. Prospective studies should be considered in future research to confirm the effect of insurance status on survival outcomes in cases of penile squamous cell carcinoma. Our retrospective research was unable to adequately capture patient demographics, comorbidities, and medication adherence; a prospective method would enable more thorough data gathering. A deeper understanding of the variables causing survival differences may also be possible by including health behavior data, such as smoking status, frequency of medical visits, and patient involvement in preventative treatment.

Limitations

There are important limitations to our study. First, the SEER registry does not provide information regarding comorbidities and hospital type. Data about these variables could not be adjusted into the analysis and warrant further research. Independent of characteristics associated to cancer, comorbidities including diabetes, cardiovascular disease, or chronic obstructive pulmonary disease (COPD) may have an impact on overall survival [27]. The authors addressed this limitation to the best of their abilities by including multiple available patient demographic variables in the Cox proportional hazard model. Second, the insurance records are a broad variable that provides details of insurance plans or coverage periods. Broad variable definitions may introduce potential selection bias and the inability to establish causality. Nevertheless, this was addressed by excluding patients with unknown insurance status or follow-up dates. Third, patients > 64 years old were excluded from this study due to the non-specificity of Medicare status. However, the nonelderly age group included in this study will most likely be affected by Medicaid expansion. Finally, this study was a non-randomized, retrospective analysis thus potential selection bias could not be excluded. Despite the study design, the data provide salient information regarding the association of health insurance disparities with cancer prognosis.

5. Conclusions

Even after controlling for demographics and tumor characteristics, our analysis shows that Medicaid patients with penile squamous cell carcinoma have higher overall and cancer-specific mortality than privately insured patients. On the other hand, survival outcomes for patients without insurance were similar to those of patients with privately insured insurance, which may be because of variations in care-seeking habits or survival bias. These results underline the necessity of focused initiatives to alleviate Medicaid patients’ unequal access to care and quality of treatment. These discrepancies may be reduced by increasing access through collaborations between the government, community, and clinicians, which would ultimately benefit vulnerable groups.