Cerebellar dysplasia related to PIK3CA mutation: a three-case series

The term PROS (PIK3CA-Related Overgrowth Spectrum) indicates a wide spectrum of overgrowth disorders related to somatic mutations in PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha) pathway. We present three cases with PIK3CA mutation and clinical characteristics encompassing MCAP (megalencephaly-capillary malformation) condition but lacking all criteria to a certain diagnosis, most of all showing prevalent and peculiar involvement of cerebellar structures at MRI (magnetic resonance imaging) mainly consisting in cortical rim thickening and abnormal orientation of folia axis. These cases expand the spectrum of intracranial MRI features in PIK3CA disorders.

CD10 and CD34 as markers in vascular malformations with PIK3CA and TEK mutations

AIMS

Vascular malformations (vMs) encompass a wide range of diseases often associated with somatic or, more rarely, germinal genetic mutations. A mutation in the PIK3Ca/mTOR pathway is more often involved in various vMs. CD10 and CD34 are cellular markers that may play a role in mesenchymal differentiation and proliferation. The aim of our study was to find a possible link between the immunohistochemical expression of CD10 and CD34 in vMs and their relationship with mutations in the PIK3CA/mTOR signaling pathway.

METHODS AND RESULTS

Our study on 58 samples of vMs showed that in endothelial cells, CD10 was significantly expressed in PIK3CA-mutated samples compared with samples without any mutation (p < 0.05), especially and even more consistently when compared with samples with mutation in other pathways (p < 0.0001). Conversely, in the same PIK3CA-mutated samples, CD34 expression in endothelial cells was significantly reduced compared with samples either without any mutation or mutations in other pathways (p < 0.05 and p < 0.0005). Compared with samples with mutations in other pathways, a significant overexpression of endothelial CD10 was also found in samples with TEK/TIE2 mutation, a gene linked to the PIK3CA/mTOR pathway (p < 0.01). However, CD34 expression was not altered. In samples with PIK3CA mutation, the CD10 expression was significantly increased in the stroma compared with samples with TEK/TIE2 gene or other gene mutations (p < 0.05).

CONCLUSION

Therefore, the CD10 and CD34 immunohistochemical profile could suggest/support the presence of mutations in the PIK3CA/mTOR pathway in samples of vMs.

Haemostatic squeezing and purse-string sutures: optimising surgical techniques for early excision of critical infantile haemangiomas

BACKGROUND/PURPOSE

Surgical excision of critical infantile haemangiomas (HMs) is usually delayed until intralesional blood flow spontaneously decreases, but fibrofatty tissue and exuberant skin invariably remain even after total involution. The aim of this study was to describe 2 surgical techniques used for early excision in 50 selected cases of HM defined critical in site or size.

METHODS

Among a total of 952 patients affected by HM observed from 1999 to 2005, 50 children (5.2%) were submitted to early surgical removal of the tumour (age range, 6-24 months). In group 1, a technique of lenticular incision and linear closure was used in 34 patients using an original clamp for haemostasis during excision. In group 2, a modified round-block excision and purse-string closure technique was performed in 16 patients.

RESULTS

Only 2 patients required transfusion to replace intraoperative blood losses. Infection, delayed wound healing, and cheloids occurred in 3 patients in group 2. Satisfactory cosmetic results have been observed in most cases in both groups at a follow-up ranging from 6 months to 6 years.

CONCLUSIONS

The range of indications for early surgical removal of critical HM might be enlarged to achieve earlier the better cosmetic results. A few surgical tricks can minimize intraoperative bleeding and optimise the surgical scar.

Thoracic outlet syndrome in paediatrics: clinical presentation, surgical treatment, and outcome in a series of eight children

BACKGROUND/PURPOSE

This report reviews the clinical presentation, surgical treatment, and outcome of 8 children treated for the thoracic outlet syndrome (TOS) during the last 3 years.

METHODS

From 1998 through 2001 31 patients were admitted to our Vascular Surgery Unit with TOS. Eight of them (25.8%) were in the paediatric age group, 8 to 16 years (mean, 13 years). No sex prevalence was found. The presenting symptoms were neurologic in 2 patients (25%) and secondary to venous flow impairment in 6 (75%). At phlebography, venous thrombosis was seen in 2 cases, and functional intermittent obstruction was seen in 4. Seven patients underwent decompressive surgical partial resection of the first rib with transaxillary or supraclavicular access. One patient was treated conservatively.

RESULTS

There were no major postoperative complications. Mean hospital stay was 2.7 days. In no patient were there signs of recurrence after a mean follow-up of 18 months (range, 3 to 36 months).

CONCLUSIONS

In the authors' experience TOS in paediatric patients occurs with the same symptoms and thrombotic complications as in adults. The same surgical strategy adopted in adult patients is advisable for affected children.

Early surgical management of Klippel-Trenaunay syndrome in childhood can prevent long-term haemodynamic effects of distal venous hypertension

PURPOSE

The aim of this study was to evaluate the authors' preliminary experience in early surgical treatment of distal venous hypertension (DVH) in children affected by Klippel-Trenaunay syndrome (KTS).

METHODS

Clinical assessment, surgical management, and outcome of 29 children (18 girls, 11 boys) affected by KTS observed from October 1998 to October 2000 were reviewed retrospectively.

RESULTS

Patients ranged in age from 8 months to 17 years (median age at surgery, 10.3 years). The clinical findings are presented. Surgical treatments included stripping of persistent marginal vein (n = 16), multiple legation of bulky varicosities (n = 10), complementary sclerotherapy (n = 14) and laser photocoagulation (n = 13), and excision of associated lymphatic malformations (n = 5). No mortality or major postoperative morbidity occurred. Follow-up period ranged from 6 months to 2 years.

CONCLUSION

These preliminary results suggest that early surgical management of DVH in KTS is safe and could be effective in preventing or minimising the long-term haemodynamic effects of DVH in absence of associated deep venous system anomalies.

Evidence-based operations in paediatric surgery

It has been assumed that only 10% of medical interventions are supported by solid scientific evidence. The aim of this study was to determine the type of research evidence supporting operations in a tertiary referral paediatric surgical unit. All patients admitted over a 4-week period to two surgical firms were enrolled in the study. All major operations carried out on each patient since birth were evaluated. Patients for whom a diagnosis was not reached were excluded. A bibliographic database (MEDLINE) was used to search for the articles published between January 1986 and December 1995 on the analysed operations. The type of evidence supporting the operations was classified as follows: I=evidence from randomised controlled trials (RCTs); II=self-evident intervention (obvious effectiveness not requiring RCTs); III=evidence from prospective and/or comparative studies; IV=evidence from follow-up studies and/or retrospective case series; and V=intervention without substantial evidence for or against results of randomised trials. Seventy operations (32 individual types) were performed on 49 patients (1-5 operations/patient); 18 (26%) were supported by RCTs (type of evidence I). Two patients (3%) received a self-evident intervention (type II); 48 operations (68%) were based on non-randomised prospective or retrospective studies (type III=13%; type IV=55%). Two patients (3%) received an operation not supported by or against convincing scientific evidence (type V). A significant proportion of operations in paediatric surgery is supported by RCTs. However, the vast majority of these trials were conducted on adult patients. Sixty-eight per cent of the operations were based on prospective follow-up studies or retrospective case series, which may not represent solid scientific evidence. More RCTs are needed in paediatric surgery.

In vivo evaluation of timing, degree, and distribution of bacterial translocation following experimental small bowel transplantation

These studies were designed to evaluate the correlation between morphologic and functional changes after heterotopic auxiliary small bowel isograft with systemic venous drainage and two ostomies in 20 Lewis rats. Morphologic damage of the graft was scored by full-thickness biopsies before surgery and 1, 3, 5, and 7 days after transplant. Functional evaluation of the graft was done, at the same time points, by urinary excretion of lactulose and mannitol injected in the proximal ostomy. The intestinal permeability was also studied by injecting Escherichia coli labeled with indium-111 oxine in the proximal ostomy. Translocation of radiolabeled bacteria was quantitated in extraintestinal tissues by radionuclide counts and number of viable organisms and in vivo by scintigraphic imaging. One day after transplant, significant graft damage (score 17.2 +/- 4.2) was observed when compared with the pretransplant value (7.3 +/- 2.6). The degree of tissue injury was similar on days 3 (15.8 +/- 3.5) and 5 (16.1 +/- 3.9) after transplant and remained high on day 7 (11.8 +/- 2.8). The lactulose to mannitol ratio showed a significantly increased permeability on day 1 (17.5) versus pretransplant values (2.6), remained high on day 3 (8.6), and returned to normal values on day 5 (2.8). Translocation of bacteria to distant organs, as measured by both radionuclide counts and number of viable organisms, was strikingly enhanced on day 1 after transplantation, compared with control animals, but returned to the pretransplant value on day 3. A good qualitative and quantitative correlation was observed between radionuclide counts in the extraintestinal organs and in vivo images obtained by scintigraphic scanning. In conclusion, in this model, timing and degree of bacterial translocation do not seem to correlate well, with the exception of the acute post-transplantation phase, with morphologic and permeability changes of the graft. Evaluation of translocation by scintigraphic imaging appears a suitable approach to study in vivo the kinetics and distribution of this process.