Molecular and clinical heterogeneity in CLCN7‐dependent osteopetrosis: report of 20 novel mutations

The “Osteopetroses” are genetic diseases whose clinical picture is caused by a defect in bone resorption by osteoclasts. Three main forms can be distinguished on the basis of severity, age of onset and means of inheritance: the dominant benign, the intermediate and the recessive severe form. While several genes have been involved in the pathogenesis of the different types of osteopetroses, the CLCN7 gene has drawn the attention of many researchers, as mutations within this gene are associated with very different phenotypes. We report here the characterization of 25 unpublished patients which has resulted in the identification of 20 novel mutations, including 11 missense mutations, 6 causing premature termination, 1 small deletion and 2 putative splice site defects. Careful analysis of clinical and molecular data led us to several conclusions. First, intermediate osteopetrosis is not homogeneous, since it can comprise both severe dominant forms with an early onset and recessive ones without central nervous system involvement. Second, the appropriateness of haematopoietic stem cell transplantation in CLCN7‐dependent ARO patients has to be carefully evaluated and exhaustive CNS examination is strongly suggested, as transplantation can almost completely cure the disease in situations where no primary neurological symptoms are present. Finally, the analysis of this largest cohort of CLCN7‐dependent ARO patients together with some ADO II families allowed us to draw preliminary genotype‐phenotype correlations suggesting that haploinsufficiency is not the mechanism causing ADO II. The availability of biochemical assays to characterize ClC‐7 function will help to confirm this hypothesis. © 2009 Wiley‐Liss, Inc.     

Hepatic Arterial Infusion of Oxaliplatin and Intravenous LV5FU2 in Unresectable Liver Metastases from Colorectal Cancer after Systemic Chemotherapy Failure

Background We have previously shown promising activity of hepatic arterial infusion (HAI) oxaliplatin combined with intravenous (IV) 5-fluorouracil (5-FU) and leucovorin (LV) as first-line chemotherapy in patients with colorectal liver metastases (CRLM) (intent-to-treat [ITT] objective response rate [ORR], 64%; secondary resection rate, 18%; overall survival [OS], 27 months). Whether this regimen could be beneficial after systemic chemotherapy failure is unknown. Methods Patients with unresectable CRLM and history of systemic chemotherapy failure were treated bimonthly with HAI oxaliplatin (100 mg/m² 2 hours) combined with IV LV and IV bolus and infusional 5FU (modified LV5FU2 regimen). Results Forty-four consecutive patients (median age 56 years; median number of prior systemic chemotherapy regimens, 2 range 1–5) were included, of whom 43 (98%) had previously received oxaliplatin (n = 34), irinotecan (n = 37), or both (n = 28). Patients received a median of nine cycles of HAI oxaliplatin and IV modified LV5FU2 (range 0–25). Toxicity included grade 3–4 neutropenia (43%), grade 2–3 neuropathy (43%), and grade 3–4 abdominal pain (14%). We observed 24 partial ORs (62%) among the 39 assessable patients (ITT ORR, 55%; 95% CI, 40–69%), including 17, 12, and 12 patients who had failed to respond to prior systemic chemotherapy with FOLFIRI, FOLFOX, or both, respectively. Tumor response allowed further R0 surgical resection (n = 7) or radiofrequency ablation (n = 1) of initially unresectable CRLM in eight patients (18%). Median progression-free survival and OS were 7 and 16 months, respectively. Conclusions HAI oxaliplatin and IV LV5FU2 is feasible, safe, and shows promising activity after systemic chemotherapy failure, allowing surgical resection of initially unresectable CRLM in 18% of patients.     

Pilot study of salvage laparoscopic prostatectomy for the treatment of recurrent prostate cancer

Study Type – Therapy (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? After primary radiation therapy or cryotherapy for prostate cancer, a biochemical‐only recurrence poses a diagnostic and therapeutic dilemma for clinicians and patients alike. Open radical prostatectomy (ORP) represents the most effective curative treatment option for these patients. Salvage laparoscopic radical prostatectomy seems to offer a safe therapeutic alternative for patients failing primary radiation or cryotherapy.

OBJECTIVE

? To evaluate feasibility, safety and oncological efficacy of salvage laparoscopic radical prostatectomy for pathology‐proven biochemical recurrence after primary radiation therapy or cryotherapy for prostate cancer.

MATERIALS AND METHODS

? This retrospective pilot study examined 15 patients from 2004 to 2010 with biochemical recurrence after external beam radiation therapy (N= 8), brachytherapy (N= 6) or cryotherapy (N= 1). ? Patients were treated with salvage laparoscopic radical prostatectomy (11 conventional, four robotic‐assisted) with bilateral pelvic dissection.

RESULTS

? Median duration of surgery was 235 min. None of the following occurred: conversion to open surgery, transfusion, urethrovesical stenosis or perioperative or postoperative mortality. One patient presented with a rectal injury, repaired using uninterrupted sutures and a colostomy. One patient had anastomotic leak treated with prolonged Foley catheterization. ? Pathological stage was pT2a in three, pT2b in three, pT3a in four, pT3b in three and pT4 in two patients; two patients had nodal metastasis. Within an 8‐month median follow‐up, 11 patients were disease‐free and three had persistent postoperative prostate‐specific antigen (PSA) elevation; the remaining patient experienced PSA recurrence after 21 months. ? Seven patients achieved continence (no pads) by 8.4 months (median), one patient manifested severe incontinence corrected by implanting an artificial sphincter, and seven patients with a 12.6‐month mean follow‐up continued to need one or two pads per day. ? Erectile dysfunction was present in five patients before surgery and in 14 patients after surgery.

CONCLUSION

? Salvage laparoscopic radical prostatectomy seems to offer a safe therapeutic alternative for patients failing primary radiation or cryotherapy. However, larger studies with longer‐term data are required.     

Traumatic pathology of antibrachial interosseous membrane of forearm

The antibrachial interosseous membrane (IOM) is taught over an average length of 10.6cm between the diaphyses of the radius and ulna bone. It looks like a stitch with fibers running from the ulna to the radius and from proximal to distal and fibers running from distal to proximal. The central band, which is the middle part of the fibers directed from distal to proximal has mechanical properties similar to those of a ligament and act as a ligamentous structure embedded in the larger membranous complex of the IOM. The interosseous membrane has a double function: it stabilizes transversally the forearm's two bones and stabilizes longitudinally the two bones by transferring loads from the radius to the ulna. Load transmission varies according to the prono-supination position, the varus-valgus constraints on the elbow and the inclination of the wrist, making interpretation of the experimental data difficult. One should consider the forearm as a whole and the interosseous membrane with the two diaphyses should be regarded as a middle radio-ulnar joint, intercalated between the proximal and distal radio-ulnar joint. Those three articulations or links between radius and ulna act synergistically to stabilize and optimize repartition of loads. Functional loss of one of these links, and of course of more than one, will severely modify the forearm function. Essex-Lopresti lesion, which represents the functional loss of all three links, is the most destabilizing forearm lesion. Imaging of the interosseous membrane is difficult. MRI allows for static imaging of the interosseous membrane but there are often artifacts due to previous trauma or surgical procedures. Dynamic sonography helps to visualize all the lesions and will probably be part of the evaluation of every severe forearm injury. Surgical treatment depends on the gravity of the lesions of the different links. Interosseous membrane reconstruction is still the most difficult technique and most of the previously reported ligamentoplasties cannot answer all the biomechanical constraints. We describe a ligamentoplasty based on the biomechanics whose technique has been validated by cadaveric experiments. First surgical cases are promising.     

F18-choline PET/CT guided surgery in primary hyperparathyroidism when ultrasound and MIBI SPECT/CT are negative or inconclusive: the APACH1 study

Purpose

To evaluate the sensitivity of F18-choline (FCH) PET/CT for parathyroid adenoma detection prior to surgery in patients with primary hyperparathyroidism and negative or inconclusive cervical ultrasound and Tc99m-sestaMIBI SPECT/CT.

Methods

We conducted a prospective bicentric study (NCT02432599). All patients underwent FCH PET/CT. The result was scored positive, inconclusive or negative. The number of uptakes and their sites were recorded. The FCH PET/CT result guided the surgical procedure (minimally invasive parathyroidectomy, bilateral cervical exploration, or other in case of multiple or ectopic foci). FCH PET/CT results were compared to the surgical and pathological findings and the follow-up.

Results

Twenty-five patients were included. Mean calcium and PTH levels prior to surgery were 2.76?±?0.17 mmol/l and 94.8?±?37.4 ng/l. Nineteen (76%) FCH PET/CTs were scored positive, 3 (12%) inconclusive and 3 (12%) negative, showing 21 cases of uniglandular disease, including 1 ectopic localization and 1 case of multiglandular (3 foci) disease. Mean lesion size was 13.1?±?8.6 mm. Twenty-four patients underwent surgery. FCH PET/CT guided surgery in 22 (88%) patients, allowing for 17 minimally invasive parathyroidectomies, 1 bilateral cervical exploration for multifocality and 4 other surgical procedures. Two patients with negative FCH-PET/CT underwent bilateral cervical exploration. When dichotomizing the FCH PET/CT results, thereby classifying the inconclusive FCH PET/CT results as positive, the per lesion and per patient sensitivities were 91.3% (95%CI: 72.0–98.9) and 90.5% (95%CI: 69.6–98.8) and the corresponding positive predictive values were 87.5% (95%CI: 67.6–97.3) and 86.4% (95%CI: 65.1–97.1), respectively.Twenty-one (88%) patients were considered cured after surgery. Their mean calcium level after surgery was 2.36?±?0.17 mmol/l.

Conclusions

Preoperative FCH PET/CT has a high sensitivity and positive predictive value for parathyroid adenoma detection in patients with primary hyperparathyroidism and negative or inconclusive conventional imaging results. Bilateral cervical exploration could be avoided in the majority (75%) of patients.

     

American tegumentary leishmaniasis: an uncommon clinical and histopathological presentation

We report a case of an unusual presentation of American Tegumentary Leishmaniasis involving a male patient with a solitary lesion on the ear lobe, persisting with minimal increase for at least six months without ulceration or related symptoms. The histological sections showed epithelial atrophy and a large number of structures consistent with Leishmania sp. amastigotes within macrophages. Treatment commenced with meglumine antimoniate resulting in regression of the condition. This report is of importance given the unusual clinical manifestation and histopathological findings in this case and the fact that there was low correlation with the extended duration of the disease.     

Repeated Stress Dysregulates κ-Opioid Receptor Signaling in the Dorsal Raphe through a p38α MAPK-Dependent Mechanism

Repeated stress releases dynorphins and causes subsequent activation of κ-opioid receptors (KORs) in limbic brain regions. The serotonergic dorsal raphe nucleus (DRN) has previously been found to be an important site of action for the dysphoric effects of dynorphin-κ-opioid receptor system activation during stress-evoked behaviors, and KOR-induced activation of p38α mitogen-activated protein kinase (MAPK) in serotonergic neurons was found to be a critical mediator of the aversive properties of stress. Yet, how dynorphins and KORs functionally regulate the excitability of serotonergic DRN neurons both in adaptive and pathological stress states is poorly understood. Here we report that acute KOR activation by the selective agonist U69,593 [(+)-(5α,7α,8β)-N-methyl-N-[7-(1-pyrrolidinyl)-1-oxaspiro[4.5]dec-8-yl]benzeneacetamide] inhibits serotonergic neuronal excitability within the DRN through both presynaptic inhibition of excitatory synaptic transmission and postsynaptic activation of G-protein-gated inwardly rectifying potassium channels (GIRKs) electrophysiologically recorded in brain slices. C57BL/6 mice subjected to repeated swim, stress sessions had significantly reduced KOR-mediated GIRK currents recorded in serotonergic neurons in DRN postsynaptically, without significantly affecting presynaptic KOR-mediated regulation of excitatory transmission. This effect was blocked by genetic excision of p38α MAPK selectively from serotonergic neurons. An increase in phospho-immunoreactivity suggests that this functional dysregulation may be a consequence of tyrosine phosphorylation of GIRK (K(IR)3.1) channels. These data elucidate a mechanism for stress-induced dysregulation of the excitability of neurons in the DRN and identify a functional target of stress-induced p38α MAPK activation that may underlie some of the negative effects of pathological stress exposure.