Proteus syndrome: report of the first Japanese case with special reference to differentiation from Klippel-Trenaunay-Weber syndrome

Excision of a large abdominal wall lipoma improved bowel passage in a Proteus syndrome patient

Proteus syndrome is an extremely rare congenital disorder that produces multifocal overgrowth of tissue. This report presents a surgical case of a large lipoma in the abdominal wall of a patient with Proteus syndrome. She was diagnosed with Proteus syndrome based on certain diagnostic criteria. The neoplasm increased in size gradually, producing hemihypertrophy of her left lower extremity and trunk, and spread to her retroperitoneum and her left abdominal wall. She experienced gradually progressive constipation, nausea, vomiting, and abdominal pain. Computed tomography (CT) of the abdomen demonstrated a large mass in the subcutaneous adipose tissue of the left lower abdominal wall which measured 12 cm × 8 cm x 6 cm in diameter and encased the left colon. This mass in the abdominal wall was excised. The weight of the excised mass was 1550 g. The histopathological diagnosis of this mass was lipoma. After surgery, the encasement of the left colon was improved, and the patient was able to move her bowels twice per day. The excision of the large lipoma in the abdominal wall contributed to the improved bowel passage in this patient with Proteus syndrome.

Bone malformations in Proteus syndrome: an analysis of bone structural changes and their evolution during growth

The radiographic follow-up of a patient with Proteus syndrome is presented. Review of radiographs obtained at 3 years 10 months, 10 years, and 17 years 8 months indicated that the rate of growth in length of the oversized tubular bones of the hands was similar to that of the normal bones of the same hand. This observation supports the view that the primary lesion occurs in the early embryonic period, when the limb bud mesenchyme cells condense and cartilage differentiates producing oversized cartilage anlages, rather than being a defect of bone cell-mediated apposition and modelling processes of bone. Additional radiographs of the pelvis and spine were obtained at age 4 years 10 months and head CT at 8 years 10 months. This pathogenetic mechanism fits well with the hypothesis of somatic mosaicism, which is at present the most credible explanation for the aetiology of Proteus syndrome. Other skeletal malformations recognized as typical of the syndrome can be interpreted as secondary adaptations to the altered mechanical conditions induced by overgrowth of bones.

A new gastrointestinal finding in Proteus syndrome: report of a case of multiple colonic hemangiomas

A patient with Proteus syndrome presented with lower gastrointestinal bleeding due to multiple colonic hemangiomas, a finding which has not been described previously in this syndrome. The patient was a 20-year-old man with features fulfilling the diagnostic criteria for Proteus syndrome. He fulfilled both general criteria (mosaic distribution of the lesions, progressive course and sporadic occurrence) and specific criteria (including epidermal nevus, disproportionate overgrowth of limbs and vascular malformations). Fiberoptic colonoscopy revealed multiple hemangiomas, 0.5-1 cm in diameter, on the left side of the colon. Some gastrointestinal complications have been reported in patients with Proteus syndrome, including rectal polyps, colonic lipomatosis, atrophy of the intestinal villi and intestinal affection with fatty wall thickening but, as far as we are aware, colonic hemangiomas have not previously been reported in this syndrome.

Reassessment of the Proteus syndrome literature: application of diagnostic criteria to published cases

The medical care of patients affected by rare disorders depends heavily on experiences garnered from prior cases, including those patients evaluated by the treating physician and those published in the medical literature. The utility of published cases is wholly dependent upon accurate diagnosis of those patients. In our experience, the rate of misdiagnosis in Proteus syndrome (PS) is high. Diagnostic criteria have been published, but these criteria have not been applied consistently and were published after many case reports appeared in the literature. We reviewed 205 cases of individuals reported to have PS in the literature and three of us independently applied the diagnostic criteria to these case reports. Our initial diagnostic congruence was 97.1% (199/205); the discrepancies in six cases were easily resolved. Only 97 (47.3%) of reported cases met the diagnostic criteria for PS; 80 cases (39%) clearly did not meet the criteria; and although 28 cases (13.7%) had features suggestive of PS, there were insufficient clinical data to make a diagnosis. Reported cases that met the PS criteria had a higher incidence of premature death, and other complications (scoliosis, megaspondyly, central nervous system abnormalities, tumors, otolaryngologic complications, pulmonary cystic malformations, dental and ophthalmogic complications) compared to those in the non-Proteus group. The cases that met the criteria were more often male, which has implications for hypotheses regarding the etiology and pathophysiology of PS. We also studied the attributes that led authors to conclude the reported patients had PS when we concluded they did not. We found that two of the diagnostic criteria (disproportionate overgrowth and connective tissue nevi) were often misinterpreted. In PS, the abnormal growth is asymmetric, distorting, relentless, and occurred at a faster rate compared to the rest of the body. Furthermore, PS was associated with irregular and disorganized bone, including hyperostoses, hyperproliferation of osteoid with variable calcification, calcified connective tissue, and elongation of long bones with abnormal thinning. In contrast, non-Proteus cases displayed overgrowth that was asymmetric but grew at a rate similar to the growth found in unaffected areas of the body. Also, the overgrowth in non-Proteus cases was associated with normal or enlarged bones together with ballooning of the overlying soft tissues. Taken together, these data show that (1) PS diagnostic criteria sort individuals with asymmetric overgrowth into distinct groups; (2) individuals with PS were more likely to have serious complications; (3) PS affects more males than females; and 4) the published diagnostic criteria are useful for clinical care and research. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299/suppmat/index.html.

Vascular anomalies in Proteus syndrome

Proteus syndrome (PS) is a complex hamartomatous disorder defined by local overgrowth (macrodactyly or hemihypertrophy), subcutaneous tumours and various bone, cutaneous and/or vascular anomalies (VA). VA are manifold in PS, but their prevalence is unknown so far. In order to further characterize PS, we studied the prevalence of VA in 22 PS patients presenting to our outpatient clinic and reviewed 100 PS patients previously reported between 1983 and 2001. The diagnosis of vascular abnormalities was made on clinical grounds and supported with imaging studies and/or histology in 12 and seven patients out of 22, respectively. Thirty-five VA were identified in 22/22 (100%) of our patients, and more than one type of VA were present in 10 of them. Vascular tumours, portwine stains (PWS), and venous anomalies (varicosities, prominent veins) were equally common. A total of 118 VA were previously reported in 70/100 (70%) PS patients; vascular hamartomas were more prevalent (56/118 = 47.5%), whilst PWS (21.2%) and venous anomalies (22.9%) were slightly less common than in our series, but there is the possibility of under-reporting. Unlike Klippel-Trenaunay syndrome, where VA are mostly confined to the hypertrophic limb, major arteriovenous anomalies are rare, and - similar to the other hamartomas and naevi observed in PS (pigmentary naevi, epidermal naevi, subcutaneous tumours, exostoses) - VA appear to be distributed at random sites on the body. We conclude that VA are among the most common findings in PS. Their varying type and distribution lend further support to the concept of somatic mosaicism.

Principles for the surgical management of patients with Proteus syndrome and patients with overgrowth not meeting Proteus criteria

BACKGROUND

Proteus syndrome is a rare, sporadic disorder consisting of disproportionate overgrowth of multiple tissues, vascular malformations, and connective tissue or epidermal nevi. Patients with Proteus syndrome present with diverse and variable phenotypes because of the syndrome's mosaic pattern of distribution.

METHODS

Eighty patients with Proteus syndrome, satisfying published diagnostic criteria, and 51 patients with overgrowth not meeting Proteus criteria were identified from the literature. Three additional patients, one patient with Proteus syndrome and 2 patients with overgrowth, were treated at the author's institutions and are discussed in detail. All nonorthopedic and noncutaneous surgical interventions were reviewed.

RESULTS

Fourteen genitourinary, 9 gastrointestinal, and 5 otolaryngologic operations were performed on patients with Proteus syndrome. Six genitourinary, 5 gastrointestinal, and 2 otolaryngologic operations were performed on patients with overgrowth not meeting Proteus criteria. Eight patients with Proteus syndrome and 4 patients with overgrowth experienced thoracic manifestations, generally diffuse cystic pulmonary lesions, but only 1 of 12 underwent surgical treatment.

CONCLUSIONS

Patients with visceral manifestations of either Proteus syndrome or overgrowth not meeting Proteus criteria should be treated in a similar manner. Lesions involving the ovaries and testes, because of the high incidence of neoplasm, should be managed aggressively. Gastrointestinal and renal lesions may be managed conservatively with frequent follow-up to minimize abdominal explorations. All patients undergoing surgery should have a thorough preoperative assessment of their airway and pulmonary reserve because of the relatively high frequency of tonsillar hypertrophy and pulmonary cystic involvement.

Proteus syndrome with widespread portwine stain naevus

Proteus syndrome is a rare condition comprising asymmetrical overgrowth of different parts of the body in association with various cutaneous abnormalities. We describe a 3-year-old boy with Proteus syndrome, who presented with hemihypertrophy of the right leg, asymmetric macrodactyly, subcutaneous masses and a widespread portwine stain interspersed with angiokeratomas on the right leg, scrotum and on the middle and left side of the back. Doppler ultrasound of the right leg did not show hypercirculation, but did reveal the absence of the right superficial femoral vein.

Proteus syndrome: new findings in seven patients

Seven children with Proteus syndrome (PS) are reported. The majority of clinical findings coincide with what is reported in the literature. New findings were blue sclerae, telecanthus, epiblepharon, endotropy, hemimegaly of the optic nerve, occipital dysmyelination and compression of the corpus callosum, craneosynostosis, decalcification and thinning of the cortical layer of long bones, and talipes equinus. The clinical findings, possible etiology, differential diagnosis, and treatment of PS are discussed.

Regional Proteus syndrome: report of an autopsy case

An uncommon autopsy case involving Proteus syndrome with multiple hamartomatous lesions in a 52 year old woman is reported. At birth, hemihypertrophy was noted on the right side of the face. Leiomyoma of the urinary bladder was extirpated at 37 years of age. She died of sepsis due to a brain abscess. At autopsy, diffuse asymmetrical lipomatosis was noted on the right side of the face, scalp, lip, oral mucosa, tongue and on the left side of the cerebellar peduncle. Multiple meningiomas, cavernous hemangiomas and osseous hypertrophy overlapped in the intracranial regions. The present case is considered as a regional type of Proteus syndrome displaying a somatic mosaicism.

Proteus syndrome with renal involvement

We report on a case of an 11 year old girl with Proteus syndrome involving both kidneys morphologically and functionally. The patient had hemihypertrophy, scoliosis, overgrowth of lower extremities, partial macrodactyly, subcutaneous lipoma, and pigmented nevi compatible with the Proteus syndrome. She also had overgrowth of the right kidney with mildly impaired function and a small left kidney with severe dysfunction. Morphological involvement of visceral organs has previously been described; however, deteriorating renal function has not previously been reported in this syndrome.