Novel approach to Gorlin syndrome: a patient treated with oral capecitabine

An evidence-based surgical algorithm for management of odontogenic keratocyst

The effective management of odontogenic keratocyst (OKC) remains a subject of interest and confusion in the oral and maxillofacial surgery literature. Currently, there is a lack of consensus regarding the most appropriate treatment for patients with OKC. Of the various treatment options available, no modality to date has been shown to demonstrate a zero or near-zero recurrence rates except wide resection with clear margins. With the prevailing dearth of evidence based surgical protocols for the management of patients with OKC in the literature, this study aims to present a surgical algorithm, based on meta-analysis results, that hopefully will be beneficial in enhancing treatment of patients with this condition. Also, new meta-analysis was done to compare between modified Carnoy's solution (MCS) and 5-fluorouracil (5-FU) in respect of recurrence rate of OKC. Using parameters like size, lesion type (primary or secondary), syndromic or solitary nature of the lesion, presence of cortical perforations, and locularity; we present a decision tree, to aid treatment planning and help attain the least chance of recurrence in the management of the OKC. There was very low-quality evidence indicating that application of 5-FU, after enucleation and peripheral ostectomy of OKCs, significantly lowered recurrence rate when compared to MCS (RR = 0.087, CI: 0.017 to 0.436, P value = 0.003).

Gorlin Syndrome

Gorlin syndrome is a rare autosomal dominant disease caused by mutations in the sonic hedgehog signaling pathway. Of particular importance is the PTCH1 gene. The disease is characterized by the development of multiple basal cell carcinomas at young ages. These tumors may present with other skin manifestations such as palmoplantar pits and with extracutaneous manifestations such as odontogenic keratocysts and medulloblastoma. Although the dermatologist may be key for recognizing clinical suspicion of the syndrome, a multidisciplinary team is usually necessary for diagnosis, treatment, and follow-up. Skin treatment may be complicated due to the large number of basal cell carcinomas and the extent of involvement. In recent years, new drugs that inhibit targets in the sonic hedgehog pathway have been developed. Although these agents appear promising options for patients with Gorlin syndrome, their efficacy is limited by adverse effects and the development of resistance.

Topical 5-Fluorouracil is a Novel Targeted Therapy for the Keratocystic Odontogenic Tumor

PURPOSE

The antimetabolite drug, 5-fluorouracil (5-FU), is used in the treatment of various cancers, including basal cell carcinomas (BCCs). The authors hypothesized that keratocystic odontogenic tumors (KOTs) would respond to 5-FU treatment because of their similarities to BCCs in molecular etiopathogenesis.

MATERIALS AND METHODS

An ambispective cohort study of the treatment efficacy of topical 5-FU on KOTs was conducted. Independent variables included the topical application of 5% 5-FU or modified Carnoy's solution (MC) after enucleation and peripheral ostectomy at the University of Toronto from 2006 through 2014. Outcome variables included time to recurrence and peripheral nerve injury. KOT specimens in these patients were immunostained with p53, Ki-67, thymidylate synthetase (TS), thymidylate phosphorylase (TP), and dihydropyrimidine dehydrogenase (DPD) antibodies. Semiquantitative staining scores were calculated for all immunohistochemistry sections examined. Descriptive statistics were computed using Fisher exact test and Kaplan-Meier analysis as appropriate with the P value set at .05.

RESULTS

Thirty-two patients with 32 KOTs were reviewed (41% in women and 59% in men). There were no KOT recurrences in the 5-FU group (n = 11), whereas there were 4 recurrences in the MC group (n = 21; P = .190). There was a significantly lower incidence of inferior alveolar nerve paresthesia with 5-FU treatment (P = .039). Immunohistochemical staining showed upregulation of TP (P < .0001) and DPD (P < .0001) and no change in TS (P > .05) in inflamed KOTs.

CONCLUSIONS

5-FU effectively treats KOTs with less postoperative morbidity than conventional treatment with MC. Low TS and upregulated TP expressions in inflamed KOTs suggest increased 5-FU efficacy in inflamed KOTs. Topical 5-FU is a novel therapy for KOTs and provides a targeted molecular approach to treatment.

Gorlin-Goltz Syndrome: An Uncommon Cause of Facial Pain and Asymmetry

Gorlin-Goltz syndrome is an underdiagnosed autosomal dominant disorder with variable expressivity that is characterized by an increased predisposition to tumorigenesis of multiple types. The major clinical features include multiple basal cell carcinomas (BCCs) appearing in early childhood, palmar and plantar pits, odontogenic keratocysts of the oral cavity, skeletal defects, craniofacial dysmorphism, and ectopic intracranial calcification. The authors present the clinical course of a 12-year-old girl presenting with facial asymmetry and pain because of previously undiagnosed Gorlin-Goltz syndrome. Early diagnosis and attentive management by a multidisciplinary team are paramount to improving outcomes in patients with this disorder, and this report serves as a paradigm for maintaining a high clinical suspicion, which must be accompanied by an appropriate radiologic workup.

Basal cell naevus syndrome: an update on genetics and treatment

Basal cell naevus syndrome is an autosomal dominant disorder that stems from mutations in multiple genes, most commonly patched 1 (PTCH1). The classic triad of symptoms consists of basal cell carcinomas, jaw keratocysts and cerebral calcifications, although there are many other systemic manifestations. Because of the broad range of symptoms and development of several types of tumours, early diagnosis and close monitoring are essential to preserve quality of life. Targeting treatment is often difficult because of tumour prevalence. Newer inhibitors of the hedgehog signalling pathway and proteins involved in proliferative growth have shown therapeutic promise. In addition, preventive medications are being devised. We propose a method for determining appropriate treatment for cutaneous tumours.

Metastatic Basal cell carcinoma accompanying gorlin syndrome

Gorlin-Goltz syndrome or basal cell nevus syndrome is an autosomal dominant syndrome characterized by skeletal anomalies, numerous cysts observed in the jaw, and multiple basal cell carcinoma of the skin, which may be accompanied by falx cerebri calcification. Basal cell carcinoma is the most commonly skin tumor with slow clinical course and low metastatic potential. Its concomitance with Gorlin syndrome, resulting from a mutation in a tumor suppressor gene, may substantially change morbidity and mortality. A 66-year-old male patient with a history of recurrent basal cell carcinoma was presented with exophthalmus in the left eye and the lesions localized in the left lateral orbita and left zygomatic area. His physical examination revealed hearing loss, gapped teeth, highly arched palate, and frontal prominence. Left orbital mass, cystic masses at frontal and ethmoidal sinuses, and multiple pulmonary nodules were detected at CT scans. Basal cell carcinoma was diagnosed from biopsy of ethmoid sinus. Based on the clinical and typical radiological characteristics (falx cerebri calcification, bifid costa, and odontogenic cysts), the patient was diagnosed with metastatic skin basal cell carcinoma accompanied by Gorlin syndrome. Our case is a basal cell carcinoma with aggressive course accompanying a rarely seen syndrome.

"PTCH"-ing it together: a basal cell nevus syndrome review

BACKGROUND

Basal cell nevus syndrome (BCNS) has existed at least since Dynastic Egyptian times. In 1960, Gorlin and Goltz first described the classic clinical triad: multiple basal cell carcinomas (BCCs), jaw keratocysts, and bifid ribs. As an autosomal-dominant disorder, it is characterized by tumorigenesis and developmental defects.

OBJECTIVE

To review the current literature on BCNS, including reports on epidemiology, pathogenesis, clinical presentation, diagnostic criteria, management, treatment, and prognosis.

METHODS

A literature review of currently available articles related to BCNS.

RESULTS

Individuals with a mutation in the tumor suppressor gene PTCH1 are predisposed to tumorigenesis and developmental defects. Clinical features include BCCs, often with onset in adolescence, jaw keratocysts, bifid ribs, craniofacial defects, palmar-plantar pits, and ectopic intracranial calcification. Despite high cure rates for individual lesions and various treatment modalities including excision, Mohs micrographic surgery, photodynamic therapy, and topical imiquimod, management of BCCs is challenging. The development of an oral hedgehog pathway inhibitor, vismodegib, has added a new dimension to current treatment algorithms.

CONCLUSIONS

Adolescents and young adults with BCC should be evaluated for BCNS. Early diagnosis of BCNS is critical for possible prevention of the devastating effects of BCCs and establishment of multidisciplinary care.

pH-responsive hydrogels with dispersed hydrophobic nanoparticles for the oral delivery of chemotherapeutics

Amphiphilic polymer carriers were formed by polymerizing a hydrophilic, pH-responsive hydrogel composed of poly(methacrylic-grafted-ethylene glycol) (P(MAA-g-EG)) in the presence of hydrophobic PMMA nanoparticles. These polymer carriers were varied in PMMA nanoparticle content to elicit a variety of physiochemical properties which would preferentially load doxorubicin, a hydrophobic chemotherapeutic, and release doxorubicin locally in the colon for the treatment of colon cancers. Loading levels ranged from 49% to 64% and increased with increasing nanoparticle content. Doxorubicin loaded polymers were released in a physiological model where low pH was used to simulate the stomach and then stepped to more neutral conditions to simulate the upper small intestine. P(MAA-g-EG) containing nanoparticles were less mucoadhesive as determined using a tensile tester, polymer samples, and fresh porcine small intestine. The cytocompatibility of the polymer materials were assessed using cell lines representing the GI tract and colon cancer and were noncytotoxic at varying concentrations and exposure times.

pH-Responsive Hydrogels with Dispersed Hydrophobic Nanoparticles for the Delivery of Hydrophobic Therapeutic Agents

To investigate the delivery of hydrophobic therapeutic agents, a new class of polymer carriers was synthesized. These carriers are composed of two components: (i) a pH-responsive hydrogel composed of methacrylic acid grafted with poly(ethylene glycol) tethers, P(MAA-g-EG), and (ii) hydrophobic poly(methyl methacrylate) (PMMA) nanoparticles. Before the P(MAA-g-EG) hydrogel was crosslinked, PMMA nanoparticles were added to the solution and upon exposure to UV light they were photoencapsulated throughout the P(MAA-g-EG) hydrogel structure. The pH-responsive behavior of P(MAA-g-EG) is capable of triggered release of a loaded therapeutic agent, such as a low molecular weight drug or protein, when it passes from the stomach (low pH) to upper small intestine (neutral pH). The introduction of PMMA nanoparticles into the hydrogel structure affected the swelling behavior, therapeutic agent loading efficiency, and solute release profiles. In equilibrium swelling conditions the swelling ratio of nanoparticle-containing hydrogels decreased with increasing nanoparticle content. Loading efficiencies of the model therapeutic agent fluorescein ranged from 38 - 51 % and increased with increasing hydrophobic content. Release studies from neat P(MAA-g-EG) and the ensuing P(MAA-g-EG) hydrogels containing nanoparticles indicated that the transition from low pH (2.0) to neutral pH (7.0) triggered fluorescein release. Maximum fluorescein release depended on the structure and hydrophobicity of the carriers used in these studies.

Amphiphilic Interpenetrating Networks for the Delivery of Hydrophobic, Low Molecular Weight Therapeutic Agents

To investigate the delivery of hydrophobic therapeutic agents, a novel class of interpenetrating networks (IPNs) were synthesized and composed of two networks: methacrylic acid grafted with poly(ethylene glycol) tethers, P(MAA-g-EG), and poly(n-butyl acrylate) (PBA). The hydrophilic P(MAA-g-EG) networks are pH-responsive hydrogels capable of triggered release of an encapsulated therapeutic agent, such as a low molecular weight drug or a protein, when it passes from the stomach (low pH) to upper small intestine (neutral pH). PBA is a hydrophobic homopolymer that can affect the IPN swelling behavior, the therapeutic agent loading efficiencies in IPNs, and solute release profiles from IPNs. In dynamic swelling conditions, IPNs had greater swelling ratios than P(MAA-g-EG), but in equilibrium swelling conditions the IPN swelling ratio decreased with increasing PBA content. Loading efficiencies of the model therapeutic agent fluorescein ranged from 21 - 44%. Release studies from neat P(MAA-g-EG) and the ensuing IPNs indicated that the transition from low pH (2.0) to neutral pH (7.0) triggered fluorescein release. Maximum fluorescein release depended on the structure and hydrophilicity of the carriers used in these studies.