Vitiligo is an acquired depigmenting disorder characterized by loss of functional melanocytes and the development of white skin patches. Its pathogenesis involves interacting mechanisms, including melanocyte susceptibility to oxidative injury, which provides a rationale for investigating interventions directed at cellular stress [1]. Beyond its visible manifestations, vitiligo can impair psychological wellbeing and quality of life. Research in children and adolescents indicates that lesion location can influence this burden, emphasizing the importance of treatment outcomes that matter to patients [2].

Treatment aims to arrest progression and promote cosmetically acceptable re-pigmentation. Narrowband ultraviolet B (NB-UVB) is an established option for generalized vitiligo. Early comparative research demonstrated the therapeutic potential of approximately 311 nm UVB irradiation [3]. Subsequently, a randomized trial comparing NB-UVB with psoralen plus ultraviolet A supported its effectiveness and favorable re-pigmentation characteristics [4]. Appropriate administration requires a defined treatment schedule, individualized dose adjustment and monitoring for adverse reactions. Recommendations from the Vitiligo Working Group address these practical considerations and highlight areas where further evidence remains necessary [5].

Despite established phototherapy benefits, interest persists in adjunctive treatments that could improve clinical response without substantially increasing treatment burden. A randomized trial investigating oral Polypodium leucotomos alongside NB-UVB illustrates the broader interest in botanical adjuncts, although findings for one preparation cannot be extrapolated to another [6]. Any proposed adjunct therefore requires direct clinical evaluation.

Pumpkin seed oil is a candidate because it contains unsaturated fatty acids and tocopherols. Analysis across twelve pumpkin cultivars demonstrated variation in oil composition, supporting the need to identify and standardize preparations used in clinical research [7]. Investigation of commercial oils further documented fatty acids, carotenoids and vitamin E constituents [8]. Comparisons also identified differences in antioxidant activity among pumpkin varieties [9]. These findings support biochemical plausibility but do not demonstrate delivery of active constituents to melanocytes or clinical effectiveness against vitiligo.

Topical pumpkin seed oil has also been investigated in recurrent aphthous stomatitis [10]. However, evidence from oral mucosal disease cannot establish efficacy in cutaneous depigmentation and potential benefits must be tested within the relevant disease setting. Accordingly, the present study compared changes in selected vitiligo lesion areas during six months of NB-UVB alone and NB-UVB combined with 100% topical pumpkin seed oil. Repigmentation patterns and reported adverse effects were also described. An oil-only group was included, but discontinuation prevented assessment throughout the planned follow-up. The investigation was intended to provide preliminary comparative evidence for further controlled research.

This comparative clinical therapeutic study was conducted at the Centre of Dermatology, Medical City, Baghdad, Iraq, between June 2016 and November 2017. Twenty-seven patients with generalized vitiligo, contributing 100 selected patches, were enrolled. Diagnosis was established through clinical history and dermatological examination. Treatment response was assessed over six months.

The study was described as single blind; however, the available documentation did not identify who was blinded or how blinding was maintained. Recruitment procedures, detailed eligibility and exclusion criteria and the method of treatment allocation were not reported. No sample-size calculation or trial-registration information was provided.

Participants and Interventions

Participants were aged 3–50 years and included 14 males and 13 females. Patients received one of three treatment regimens. Group A included five patients with 16 patches who applied 100% topical pumpkin seed oil twice daily. Group B included 12 patients with 42 patches who received narrowband ultraviolet B (NB-UVB) phototherapy twice weekly for six months. Group C included 10 patients with 42 patches who applied 100% topical pumpkin seed oil twice daily and received NB-UVB phototherapy twice weekly for six months.

All five patients in group A discontinued follow-up after two months. The original report attributed their withdrawal to dissatisfaction with the treatment. Consequently, six-month outcomes were available only for the two phototherapy groups, comprising 22 patients and 84 patches.

The available documentation did not specify the oil manufacturer, botanical identification, extraction procedure, compositional analysis, storage conditions or quantity applied per treatment. The timing of topical application relative to phototherapy was also unreported. Details of the phototherapy equipment, emission spectrum, starting dose, dose increments, maximum dose, protective measures and dose-adjustment procedures were unavailable. Adherence, treatment interruptions and concomitant treatments were not sufficiently documented.

Outcome Assessment

Selected vitiligo patches were evaluated at baseline and after two, four and six months. Treatment response was assessed using lesion surface area, expressed in square centimeters and summarized as mean±Standard Deviation (SD). Anatomical distribution and re-pigmentation patterns were also recorded. Re-pigmentation was classified as perifollicular, marginal or mixed.

For the present report, percentage reduction in mean lesion area was calculated using the following formula:

\[ \text{Reduction in mean lesion area (\%)}= \frac{\text{Baseline mean area}-\text{Follow-up mean area}} {\text{Baseline mean area}}\times100 \]

This calculation describes the relative change in the group mean and does not represent the average of individual lesion percentage reductions.

The original documentation did not describe the lesion-measurement technique, criteria for selecting target patches, identity of the outcome assessor or operational definition of disease stability. Definitions used to distinguish re-pigmentation patterns were also unavailable. Adverse effects were reported descriptively, without a documented standardized assessment schedule or severity-grading system.

Statistical Analysis

Available aggregate data were summarized descriptively. Continuous variables were presented as mean±SD and categorical variables were expressed as frequencies and percentages. Percentage reductions in mean lesion area were calculated from the detailed tabulated means. These calculations were used consistently where the original narrative percentages differed from the reported mean values.

Reported p-values were transcribed from the detailed source tables. Values originally presented as P = 0.000 were expressed as p<0.001. Statistical significance was defined as p<0.05. The original report included analysis-of-variance statistics, but the analytical model, degrees of freedom and tests underlying the individual comparisons were insufficiently documented.

No additional inferential analyses were performed because individual patient and lesion records were unavailable. Multiple patches were assessed within each patient and each patch was measured repeatedly. These dependencies require consideration in the statistical analysis, but the original documentation did not establish whether they were addressed. Accordingly, the reported p-values should be interpreted cautiously and do not establish an adjusted patient-level treatment effect. Differences between within-group p-values were not interpreted as evidence of superiority between treatments.

Ethical Considerations

The available study documentation did not provide the name of an approving ethics committee, an approval number or an approval date. Procedures for obtaining informed consent, parental or guardian consent, age-appropriate assent and permission to publish clinical photographs were also not documented. Their absence from the supplied report does not establish whether these procedures occurred.

Of 27 enrolled patients, 22 patients with 84 patches remained in the two phototherapy groups through the reported six-month assessment. Overall attrition was 5/27 (18.5%), confined to group A. The five oil-only participants included four males and one female, aged 6–40 years. Across the enrolled cohort, the source reports a mean age of 21.2±12.4 years. Selected lesion areas ranged from 0.5 to 15 cm², with a reported overall mean of 4.16±3.44 cm²; the denominator for this overall mean was not specified.

Table 1 summarizes the two groups with six-month outcome data. Their baseline profiles were descriptively different, including age, sex and reported disease activity; no adjusted comparison was available.

NB-UVB, narrowband ultraviolet B; SD, standard deviation. Patient percentages were calculated using the group patient counts. Source inconsistencies are listed in the appendix.

Table 1: Baseline Characteristics of the Phototherapy Groups

Mean lesion area decreased progressively in both groups (Table 2). For NB-UVB alone, the reported within-group comparison reached statistical significance at six months. In the combination group, reported comparisons were significant at four and six months. These within-group findings cannot determine whether one regimen was superior to the other.

Values are mean±SD for 42 patches per group. P values are transcribed from source Tables 1 and 2 and were not recalculated. Their test specification and handling of clustering require confirmation.

Table 2: Lesion Area During Treatment and Reported within-Group Comparisons

Calculated reductions in group mean area were greater in the combination group at each follow-up visit, but the source reported no significant between-group difference in lesion area at any visit (Table 3).

Table 3: Calculated Reductions in Mean Lesion Area and Reported Between-Group Comparisons

At six months, the absolute mean-area reductions were 2.033 cm² with NB-UVB alone and 2.558 cm² with combination treatment. Confidence intervals for these changes could not be calculated from the available summaries.

Reduction percentages were recalculated from the three-decimal means in Table 2. Between-group P values are retained from source Table 3 and refer to the reported comparison of lesion areas, not a newly tested difference in percentage change.

 The trunk was the most frequently represented site in the NB-UVB group, while trunk and upper-limb lesions were equally represented in the combination group (Table 4). Perifollicular re-pigmentation predominated with NB-UVB alone, whereas mixed re-pigmentation predominated with combination treatment. These distributions were descriptive; no validated between-group test was available.

Table 4: Anatomical Distribution and Re-pigmentation Patterns

Each distribution uses 42 patches as the denominator. Anatomical sites and re-pigmentation patterns are separate classifications. Percentages may not sum to 100 because of rounding.

Tolerability

Some patients receiving NB-UVB alone experienced transient erythema, burning or itching around phototherapy exposure. The source describes these effects as tolerable and reports continuation of treatment. No local or other adverse effects were reported in the combination group. Event counts, severity grades and systematic monitoring procedures were not provided, preventing a quantitative comparison of tolerability.

The text below is 500 words, excluding headings, citation markers and references. References 1–10 retain the introduction numbering; 11–25 are additional references.

Both phototherapy groups showed progressive reductions in mean lesion area over six months. Combination treatment produced a numerically greater reduction, but the between-group comparison was not statistically significant (p = 0.687). Consequently, these findings do not demonstrate superiority of pumpkin seed oil supplementation. Comparing within-group significance levels cannot establish a difference between treatment effects [11].

The observed improvement is compatible with established NB-UVB efficacy [3–5]. Experimental evidence indicates that irradiated keratinocytes can support melanocyte proliferation and migration [12], while clinical investigations document responses in children and variable longer-term outcomes [13,14]. Response also depends on anatomical location and patient characteristics [15]. Baseline imbalances therefore complicate interpretation of the present comparison.

Trials evaluating antioxidant supplementation alongside phototherapy provide context for investigating adjunctive approaches [6,16,17]. However, a placebo-controlled pseudo catalase trial illustrates that biochemical plausibility does not necessarily translate into additional clinical benefit [18]. Results obtained with other antioxidants cannot establish effectiveness of topical pumpkin seed oil.

Pumpkin seed oil contains potentially relevant fatty acids and tocopherols, but composition and antioxidant activity vary between preparations [7–9]. Studies describing membrane lipid alterations and mitochondrial dysfunction in vitiligo support investigation of oxidative mechanisms [19,20]. Nevertheless, the present study measured neither oxidative biomarkers nor tissue exposure. Proposed antioxidant and anti-inflammatory effects remain hypotheses. Evidence from aphthous stomatitis involves a different disease and cannot validate treatment of vitiligo [10]. Complete withdrawal from the oil-only group also prevents assessment of independent efficacy.

Perifollicular re-pigmentation predominated with NB-UVB alone, whereas mixed re-pigmentation predominated with combination treatment. These descriptive differences require confirmation using standardized photography and blinded assessment. Selected lesion-area reduction is not equivalent to whole-patient improvement; instruments such as the Vitiligo Area Scoring Index and Vitiligo Extent Score could improve comparability [21,22]. Patient-reported outcomes are also important because visible improvement may not capture psychological benefit [2,23,24].

No adverse effects were reported with combination treatment, but incomplete event counts and the small sample prevent firm safety conclusions. Without a vehicle control, any oil-specific contribution cannot be separated from emollient effects. Cost effectiveness was not evaluated.

Limitations

Limitations include the small, single-center sample, complete attrition from one arm, insufficiently described allocation and blinding and uncertain measurement procedures. Multiple lesions within patients and repeated observations create dependence that requires appropriate statistical modeling. Missing individual records prevented reanalysis and inconsistent source values required reconciliation. Confidence intervals, standardized treatment specifications, adherence data and post-treatment follow-up were unavailable. Future randomized trials should use a standardized oil preparation, matched vehicle, blinded assessment, prespecified outcomes and transparent participant-flow reporting consistent with established trial-reporting principles [25]. Analyses should account for patient-level clustering and report effect estimates with confidence intervals.

Longer observation should establish whether repigmentation persists after phototherapy stops and whether any numerical advantage is meaningful to patients rather than reflecting measurement variation, baseline differences, or the natural variability of treatment response.

Both NB-UVB regimens were associated with reduced lesion area, but an additional benefit from pumpkin seed oil was not statistically demonstrated. Oil monotherapy could not be evaluated. The findings support further controlled investigation rather than routine clinical adoption.

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