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Paper text:
the covered exstrophy is an extremely rare variant of exstrophy  epispadias complex wherein the incomplete closure of the anterior abdominal wall does not include the skin ; the entirety of the skin guarantees an easier management and lower distress comparing with the classic bladder exstrophy . if the bladder exstrophy is rare , with an incidence ranging from 2 to 5 cases per 100,000 live births and a male to female ratio of 2.3:1 , the cover exstrophy is even more rare .
the risk to develop a bladder cancer in patients with bladder exstrophy is significantly higher than the age - matched population , and some studies estimate this risk is as high as 700-fold greater .
bladder cancer in exstrophic bladder is generally a high undifferentiated carcinoma , more often adenocarcinoma resembling a colorectal carcinoma , rarely a squamous carcinoma , or urothelial carcinoma . in the event of cancerization , besides a radical cystectomy and a urinary derivation , an abdominal reconstruction is required if skin is involved .
pedicle flaps are the best choice to restore full thickness defect of the lower abdominal wall .
usually these flaps are harvested from the tight as myocutaneous or fasciocutaneous flaps and most of them are based on the system of the circumflexes femoral artery .
the most used flaps are the tensor fascia lata ( tsl )   and the anterolateral tight flap.[79 ] less used for this kind of reconstruction are the rectus femoris and the vastus laterals flap .
the gracilis flap   has also been used in abdominal reconstruction , but it belongs to a different arterial system , less used in this type of reconstruction .
the vac therapy is an option to repair septic wound of the abdomen with a second - intentions healing .
the aim of this paper is to report a case of a cancerization of covered exstrophy and its surgical management . because of the oncological resection , we removed the tumor with a full thickness demolition of the lower abdominal wall and pubic region .
the reconstruction was made with a pedicle myocutaneous vastus lateralis muscle sparing flap   that included in the flap a portion of fascia lata .
a 47-year - old caucasian woman with a known - covered exstrophy , uterus didelphys , and external genital malformations ( figure 1 ) , that did not affect her ability to procreate ( two caesarean sections ) , presented with recurrent macroscopic haematuria .
ct scan showed a left third grade hydronephrosis associated to a dysmorphic bladder , with a endoluminal neoformation of 10  cm of maximum diameter with irregular margins which appeared strictly in contact with the near organs and extending up to the abdominal skin .
after a trans - urethral biopsy ( tur - b ) showing an infiltrating urothelial high - grade carcinoma ( immunehistochemical exam [ hic ] : pankeratin ae1/3 + ck7 + ck20 ) , based on the rapid tumor growth , a neoadjuvant chemotherapy based on cisplatin and gemcitabine was performed .
no clinical response was obtained and the ct scan showed a worsening of local invasion .
as a radical surgical excision was still achievable , a radical cystectomy with a wide iliac - obturator lymphadenectomy and bilateral urostomy was then performed .
preoperative view ( a ) and large abdominal wall defect after resection of the tumor ( b ) .
the suprapubic skin was removed and the defect was reconstructed by a right myocutaneous vastus lateralis muscle - spearing flap .
a neobladder was not reconstructed.[14 ] cranially to the bispinoiliac line , the rectus abdominis muscles were sutured along the midline , while caudally , a full - thickness defect extended from the abdomen to the vaginal orifice ( 10    16  cm ; figure 1 ) .
the size of the demolition required the use of a vascularized tissue to cover the exposed intestine .
the advanced stage of the tumor and the lower expectative of life required a fast and safe reconstruction so we decided to use a myocutaneous vastus lateralis muscle - spearing flap from the right thigh .
only the superficial partition of the vl was harvested , preserving its nerve supply , and a portion of the fascia lata was included in the flap .
the flap was passed under the rectus femoris muscle and a subcutaneous tunnel to reach the defect ( figure 2 ) .
the fascia lata and the vastus lateralis aponeurosis were sutured laterally to the residual abdominal fascia and cranially to the rectus abdominis muscles .
the vl filled the dead space in the pelvic floor and was sutured to the upper border of the vagina and its skin island provided an additional resurfacing layer ( figure 3 ) .
postoperative period was uneventful , and the flap showed no sign of ischemia or infection .
intraoperative view showing the musculo - cutaneous muscle - sparing vastus lateralis flap including a portion of fascia lata ( b and c ) and the pedicle of the flap ( a ) .
the tunnel in the inguinal region ( a ) and the insetting of the flap ( b ) .
ct scan also showed a multidistrict metastatic disease and eight months after surgery the woman died .
exstrophy of the bladder is part of a spectrum of anomalies involving the urinary tract , the genital tract , the musculoskeletal system , and sometimes the intestinal tract . despite an acceptable quality of life
can be achieved with modern reconstructive technique , the disease is burdened by a high incidence of bladder cancer .
adenocarcinoma is the most common histological type in bladder exstrophy , accounting not only for over 90% of all carcinoma in these patients , but also squamous cell carcinoma or urothelial carcinoma may develop . the woman we observed had a locally advanced sarcomatoid urothelial carcinoma . to obtain a radical treatment , removal of a part of the abdominal wall
the selection of reconstructive techniques in cases of patients with a short - life expectancy must be targeted to a very fast healing that gives them the possibility of receiving early adjuvant therapies with a good quality of life . to repair the defects and cover the exposed bowel ,
, we have harvested a myocutaneous vastus lateralis muscle - sparing flap , a safe and useful , yet not popular , option . in literature ,
several techniques have been described for the reconstruction of the abdominal wall by local flaps .
the pedicled tfl used to be the workhorse to repair abdominal wall defects but it is often bulky and poorly vascularized .
the alt flap allows to reconstruct big defects , but due to the lack of a muscular component in the flap , it does not allow for a functional reconstruction .
vacuum - assisted closure ( vac ) therapy may gradually close the abdominal wall defects over the bowels generating granulation tissue that can be grafted .
this technique requires long time of healing , is associated to an elevated risk of fistula formation when the vac is in direct contact with bowel , and does not allow functional reconstruction of the abdominal wall .
we have often used the myocutaneous vastus lateralis flap in the repair of the head and neck defects after cancer resection and we believe it is a very versatile and reliable flap , both free and pedicled . the anterolateral thigh area donor site is ideal for the repair of abdominal wall because it remains outside the areas of scarring due to any previous abdominal operations . the vastus lateralis myocutaneous flap can cover large defects ( up to 20    10  cm ) ; the possibility of including a large portion of the fascia lata helps to strengthen and stabilize the abdominal wall .
the selective harvest of only a partition of the vastus lateralis reduces morbidity of the donor site .
the intermediate and deep partitions of the vastus lateralis remain in situ and the innervation of the other heads of the quadriceps remains intact .
the flap is tunneled under rectus femoris muscle so as to facilitate the insetting of the flap and reduce the possibility of twisting or compression of the pedicle .
there are no big disadvantages connected to the use of this flap , one of which could be the necessity to use a skin graft to cover the donor site when the skin portion of the flap is larger than 810  cm .
this technique allowed for a functional reconstruction of the abdominal wall , that would have prevented the development of future incisional hernias should the patient had a longer survival .
unfortunately , the fate of the patient was not favorable and , because of the advanced disease , the woman died eight months after surgery with evidence distant metastases .
bladder exstrophy is a predisposing factor for the development of not only advanced bladder cancer , usually adenocarcinoma but , as the case we report , also undifferentiated urothelial carcinoma .
patients with bladder exstrophy , even in the covered form , must be followed in order to early diagnose the malignant disease as treatment of advanced disease remains challenging .
it often requires full - thickness excision of the abdominal wall and a subsequent reconstructive procedure .
a myocutaneous vastus lateralis muscle - spearing flap is a safe and versatile option for morphofunctional reconstruction of large abdominal defects .
the authors report no conflicts of interest . the authors alone are responsible for the content and writing of this article .
abstractwe report a case of a woman affected by covered exstrophy , uterus didelphys and external genital malformation presenting with advanced bladder cancer . 
 after neoadjuvant therapy and anterior pelvic exenteration , the abdominal wall was reconstructed with a pedicled myocutaneous muscle - sparing vastus lateralis flap .