The outcomes of surgical management options for adult acquired buried penis

Functional and surgical outcomes after surgical correction of adult acquired buried penis (AABP) are limited in the current literature. We retrospectively recruited patients underwent surgical treatment of AABP in a single institution from 2017 to 2021. Surgical repair was classified according to surgical complexity following Pariser-Santucci’s classification. The primary endpoint of the study was the recurrence-free rate survival. The secondary endpoints were surgical, functional and patients’ reported outcomes. Overall 28 patients were included in the study. Median follow-up was 27.5 (18.5–34.5). The most common complaints at presentation were sexual (53.6%) and voiding (39.3%) dysfunction. Surgical management steps ranged from circumcision to more complex procedures, such as suprapubic fat pad excision, abdominoplasty and/or penile shaft skin grafting. Overall postoperative complications were recorded in 32.1%. High-grade complications (Clavien≥3) occurred in 7.1%. One-year recurrence-free survival was 88.7%. Postoperatively IPSS and IIEF-15 questionnaires showed a significant improvement in urinary 8 (0–12) vs 2 (0–3), p = 0.03 and sexual function 37 (23–68) vs 68 (45–72), p = 0.001 respectively. Overall, patients reported functional improvement and 93.8% experienced a positive impact of QoL. AABP surgical repair, despite the high incidence of complications, seems to allow satisfactory outcomes and a significant improvement in patients’ QoL.


INTRODUCTION
Adult acquired buried penis (AABP) is a condition characterized by envelopment of the penis by the surrounding abdominal/ suprapubic tissues.Chronic inflammation and persistently moist genital environment lead to a combination of penile dartos dysfunction, skin breakdown, scarring and contracture of peri-genital tissues, which ultimately lead to penile burying [1].This condition was originally described by Dr. Keyes in 1917 [2].
Multiple factors may contribute to the onset of AABP, obesity being by far the most important one [3].The incidence of AABP has increased notably, mirroring the rising incidence of obesity and metabolic syndrome in western population [4,5].Other factors contributing to AABP include aggressive circumcision [6], following surgical treatment for penile cancer (PC) [7], or chronic dermatological conditions such as lichen sclerosus (LS) [8,9].
AABP can significantly impact patients in a multitude of ways: sexual and voiding dysfunction [7,10], difficulty maintaining hygiene [7,10] as well as psychological impacts of impaired self-esteem and depression [11] are some examples of the ways AABP can impair quality of life.AABP may also increase the risk of PC [12] and urethral stricture [13].
In early stages of AABP risk factors may be approached through conservative interventions, such as weight loss [14], soft tissue infections management and treatment of LS by application of topical steroids- [15] Whilst these remain important strategies, weight loss does not often significantly affect pubic adipose distribution and as such, penile burying may not be resolved solely by weight reduction [16].
Whilst some patients may present earlier with dermatological issues including LS or phimosis, AABP is commonly diagnosed at an advanced stage with surgery representing the only suitable treatment [7,17,18].
Surgical approaches vary from a circumcision to more complex interventions [19,20].The latter include release of the penis from surrounding tissues, suspensory and fundiform ligament division, skin grafting or genital skin local flaps for penile shaft reconstruction, scrotoplasty, suprapubic fat pad excision and abdominoplasty [17,18].
The study aims to determine the recurrence-free survival rate (RFR) and to describe surgical, functional and PROs following AABP surgical management.

MATERIALS AND METHODS Study setting and patients
From November 2017 to April 2021, 28 patients whom underwent AABP surgical management in a single tertiary referral center were included in the study.Surgery was performed by the senior surgeon (MF).Inclusion criteria were a diagnosis of AABP in patients over the age of 18. Exclusion criteria were transgender patients, patients affected by Peyronie's disease, those who had had previous major AABP surgeries, patients with incomplete data in either preoperative evaluation, operation notes or follow-up.
This study complies with the Declaration of Helsinki and was performed according to ethics committee approval (Protocol Number 00195/2021).Written informed consent was obtained from every patient as well as the consent to publish pictures and data prior to enrollment.
Surgical repair principles and techniques (Fig. 1) Preoperative assessment.Surgical planning was based on a detailed preoperative physical evaluation.The abdomen, suprapubic area and genitalia were examined in both supine and standing positions.Close attention was paid to the laxity and excess of peri-genital tissues, genital skin quality and availability.Surgical classification.Following the Pariser-Santucci classification [19], all surgical interventions were classified in five categories considering the degree of technical complexity.
Patients fitting group I or II are considered of a low surgical complexity.Those included in group III-V are considered of a high surgical complexity.Patients whom underwent multiple surgical procedures are classified according to the higher grade performed.Surgical technique.All surgeries were performed under general anesthesia.Antibiotic prophylaxis with Cefazolin 2 gm IV was administered 30 min prior to surgical incision.If necessary, antibiotic therapy was administered during the hospital stay.All patients received antithrombotic prophylaxis with low-molecular-weight heparin.
Grade I-externalization of the penis: In case of phimosis, a circumcision was performed utilizing a sleeve technique [19].Any poorquality shaft skin was excised.To optimize penile shaft exposure a penile degloving with adhesiolysis of tethering dartos bands was performed.In some cases, a division of the suspensory ligament, or a fixation of the pubic skin to the pubis was carried out.
Grade II-penile skin excision and skin grafting or scrotal flap reconstruction: When insufficient skin was available to cover the penile shaft after complete debridement, reconstruction was performed using either of the following two techniques [19]: a. Skin grafting: The Buck's fascia serves as a vascularized bed for the graft.A 0.016 inch thick split thickness skin graft (STSG) is fashioned using an air dermatome, or a full thickness skin graft (FTSG) harvested from non-hair-bearing areas (inner thigh, abdomen).These were quilted to the underlying Buck's fascia with 4-0 poliglecaprone monofilament absorbable.Quilting sutures were applied, being mindful of the neurovascular bundle to minimize the risk of neurovascular injury.b.Scrotal pedicled flap: Two rectangular fascio-cutaneous flaps were isolated from the scrotum.The vascular pedicle was based on external pudendal vessels.Flaps were rotated to cover the penile shaft a contentive dressing was applied.Grade III-Scrotoplasty or scrotal debulking: In case where the scrotum attaches distally along the penile shaft, the skin and the superficial dartos is incised to create a lengthening V-Y or Z plasty [19].
Grade IV-Escutcheonectomy/suprapubic fat pad removal: Perigenital and suprapubic fat pads were commonly managed with suprapubic panniculectomy, a technique employed in the management of bariatric patients with redundant and hanging suprapubic tissues [19].A transverse elliptical incision of the suprapubic skin was created with isolation and excision of all underlying fat, to the level of the anterior rectus sheath.The caudal margin of the fascio-cutaneous flap was fixed to the periosteum of the pubic bone to improve penile externalization.A suction drain was applied for 48 h after surgery to reduce the risk of seroma/hematoma.
Grade V-Complete abdominal panniculectomy: Panniculectomy consists of removing excess hanging skin and subcutaneous fat of the lower abdomen down to the rectus fascia by an elliptical-shaped incision above the mons pubis [19].A suction drain was applied for 72 h after surgery to reduce the risk of seroma/hematoma formation.

Outcome measures and statistics
Data were retrospectively extrapolated from operation notes and clinical records.Oversights and bias were prevented through a double-blinded review of all data (MF and MP).
RFR was the primary endpoint of the study.AABP recurrence was defined as the need for any surgical intervention due to re-burying of the penis.Surgical and functional outcomes were the secondary endpoints.Perioperative (<90 days) complications were evaluated and classified according to the Clavien-Dindo classification [35].A comparative study addressed the low complexity (<III) and the high complexity group (≥III).The International Index of Erectile Function (IIEF-15) [36] and the International Prostate Symptoms Score (IPSS) [37] were used to assess erectile and urinary function at baseline and 12 months postoperatively.A 6-item "ad-hoc" questionnaire (Fig. 2) evaluated PROs at 12 months after surgery.
The normality of variables' distribution was tested by the Kolmogorov-Smirnov test.The categorical variables were described using frequency and percentage.Differences between groups were tested by the Chi-square test or the Fisher's exact test.Continuous variables with normal distribution were described using mean and standard deviation (SD), whereas variables with non-normal distribution were described using median and interquartile range (IQR).Differences between groups were assessed by the Student's T test or the Mann-Whitney U test.A p-value <0.05 is statistically significant.RFR survival over time was estimated by Kaplan-Meier analysis.The log rank test was applied to identify any significant difference in terms of survival between groups.Statistical analyses were performed using the Statistical Package for the Social

YES NO
1. Overall, are you satisfied with the intervention?
2. Did the surgery have a positive impact on the quality of your urinary function?
3. Did the surgery improve your genital hygiene?
4. Would you recommend the surgery to a friend/family member?
5. Did the surgery improve your quality of life?
6. Did the surgery have a positive impact on the quality of your sexual life?

Patient characteristics
35 patients underwent surgical correction of AABP in our institution.7 patients were excluded as they did not fulfilled the inclusion criteria (2 had Peyronie's Disease and 5 had previous major AABP surgeries).28 patients fulfilled the inclusion criteria and were included in the study.Patients who had had any major AABP surgery previously (excludes circumcision) were excluded from the study.Patient demographics are summarized in Table 1.Median follow-up was 27.5 months (IQR 18.5-34.5).The mean body mass index (BMI) was 32.2 kg/m 2 (SD ± 6).The most common risk factor/comorbidity was hypertension (60.7%, 17 patients).
Nearly two thirds of the patients (64.3%, 18 patients) had previously undergone circumcision and LS was newly identified in 57.1% of cases (16 patients).No significant differences in descriptive features were identified between groups.Sexual (53.6%) and voiding (39.3%) dysfunctions were an extremely common complaint at presentation (Fig. 3).

Surgical outcomes
A summary of the surgical outcomes is presented in Table 2. Most patients (78.6%, 22 patients) underwent a complex surgical repair.STSG was used in 25% of the cases (7 patients) and FTSG was applied in the other cases (28.6%, 8 patients).Table 3 summarizes postoperative complications, which were recorded in 9 patients (32.1%); high-grade complications (Clavien ≥3) occurred only in two cases (7.1%), both relating to patients in the high complexity group.No significant differences were identified between the high and low complexity group concerning the types of complications, except for the formation of seroma that was observed in the low complexity group (p = 0.03).
Functional outcomes 16 patients (57.1%) answered the questionnaires (Table 5).IPSS showed a significant improvement in urinary function.Indeed median preoperative value varied from 8 (0-12) to 2 (0-3) in postoperative settings (p = 0.03).On the regards of sexual function, IIEF-15 increased from a median value of 37  in preoperative settings to 68 (45-72) postoperatively (p = 0.001).Most patients reported an improvement PROs in all domains.An overall improvement of QoL was recorded in 93.8% (15 out of 16 patients) after surgery.

DISCUSSION
AABP is a debilitating condition, as it interferes with a variety of aspect of personal life.Voiding function, social embarrassment, skin hygiene, sexual dysfunction can all be affected and unsurprisingly, impact both quality of life and self-esteem [7,10,11].Frequent failure with first line or conservative measure [14,15], as well as frequent delay in presentation may contribute to surgical management often remaining the only option [7,17,18].
In 2016 Tausch et al. [34] identified eight categories for AABP along with a specific therapeutic algorithm.In 2018 Pariser et al. [19] described a simplified classification system which included Table 4. Surgical outcomes between full thickness skin graft and split thickness skin graft.five categories and two groups based on the surgical complexity.The latter classification was recently adopted in a systematic review by European Association of Urology Sexual and Reproductive Health working panel [1].We also used this classification system for the present study.

Variables
Although AABP affects mainly young and middle-aged men, in our study the median age of patients was 60.5 years.As reported in the current literature [11,17,19,29], 32% of patients in our study were obese, supporting the correlation between AABP and obesity.When evaluating RFR following AABP surgery, Pariser et al. [19] reported a higher RFR survival in the low-complexity group as compared to the high-complexity group (100% vs 86%) and an overall success rate of 91%.Similar overall success rates were reported by Hampson et al. [7] (85%) and Tausch et al. [34] (88%).Our recorded one-year RFR survival rate was 88.7%, which is comparable with the published rates.When considering the oneyear RFR rate according to the surgical complexity, a higher value was found in the more complex surgical group, compared to those with low complexity (91% vs 80%, respectively).Several confounding factors should be considered when analyzing these findings.Firstly, the number of patients assigned to the low complexity group was limited.Additionally, some patients due to major comorbidities, despite being candidates to a major surgical procedure (high complexity) according to their clinical appearance, were switched to a less invasive surgical procedure (low complexity).With the lack of larger studies demonstrating evidence for particular surgeries, we believe the key point is to tailor the best surgical option for every patient.AABP repair unfortunately incurs significant risk of complications, the most frequently reported being wound dehiscence and infections.In 2017 Voznesensky et al. [11] reported a wound infection rate of 75% as the only complication in their study.In the same year, Hampson et al. [7] described a postoperative complication rate of 33%, with high-grade complications in 17% of the cases.They also reported that a higher BMI was associated with a higher wound complication rate and that previous bariatric surgery protected against postoperative complications.Similarly, Pariser et al. [19] reported high-grade complications in 16% of the patients with an overall complications rate of 65%.They reported a lower complication rate in the low complexity group (50%) as compared to the high complexity one (73%).Cocci et al. [29] reported a postoperative surgical complication rate of 14.9% with only 4.3% incidence of high-grade complications.
We identified an overall complication rate of 32.1%.There were no statistically significant differences between the two groups of treatment (33.3% in low-complexity repair vs 31.8% in highcomplexity repair, p = 0.9).High-grade complications were recorded in 7% of cases which is in line with recent study [29].Although no statistically significant differences were identified, STSG resulted in a better graft take in comparison to FTSG (85.7% vs 62.5).
Regarding functional outcomes, recent studies report a significant improvement in all functional domains following AABP surgery [7,10,11,29,32].Varied validated questionnaires assessed patients' voiding, erectile functions and behavioral changes in terms of genital hygiene [7,10,29,32] An improvement in micturition was described in 87-91% of cases, while erectile function and sexual penetrative ability improved to 41% and 97% respectively.All patients found genital hygiene easier and more satisfying.Cocci et al. [29] used the Hospital Anxiety and Depression Scale (HADS) [39] to evaluate AABP psychological impact.They reported a reduction in depressive symptoms among affected men.Similarly, Rybak et al. [40] found a reduction in depressive symptoms from 64% to 18% post-AABP surgery.In our study the benefit in voiding was more pronounced in the high complexity group as compared to the low complexity group.Similarly, IIEF-15 scores improved after surgery.In terms of patient's sexual function a greater improvement was recorded in the low-complexity group as compared to the low complexity group.93.8% of patients stated that they would choose to have the surgery again and considered that the surgery had a positive impact on their quality of life.It should be noted that in our study, 16 of the 28 patients have correctly completed the validated questionnaires, 12 patients were excluded as they did not answer the questionnaires, or the questionnaires were not filled in correctly.
Our study has several limitations including its retrospective nature, the limited number of patients enrolled and number of completed post-operative questionnaires, the relatively limited follow-up and the lack of a shared classification for AABP surgical management.Another limitation is the absence of validated Italian IIEF and IPSS questionnaires to be used, nevertheless since those are important tools for evaluating functional outcomes and every patient could understand the English language, the original version of IIEF and IPSS were used.Further research in multicentric prospective settings with longer follow-up periods is needed to confirm our data.CONCLUSION AABP surgical repair is an effective surgical solution despite its reasonably high complication rate.Addressing AABP improves multiple functional outcomes and allows psychological and social improvements.

Fig. 1
Fig. 1 Surgical techniques.A STSG reconstruction; B, C Scrotal flap reconstruction; D, E Type V reconstruction; F Final result type V.

Fig. 4
Fig. 4 Kaplan-Meier curve estimates survival over time.A Overall RFR survival; B RFR survival among the two treatment groups.
OSASObstructive sleep apnea syndrome, BMI Body Mass Index.aPariser-Santucci classification.bFisher's exact test.cStudent's T test.dMann-Whitney U test.* Pariser-Santucci classification 19 Overall Low complexity (I, II) * High complexity (III, IV or V)* Fig. 3 Clinical presentation report divided by groups of treatment.Clinical presentation reported by all 28 patients affected by AABP and divided by groups of treatment.
a Pariser-Santucci classification.b Chi-square test.c Fisher's exact test.d Student's T test.

Table 3 .
Postoperative complications and skin grafting surgical outcomes.
a Pariser-Santucci classification.b Mann-Whitney U test.c Fisher's exact test.