[Solitary bone plasmocytoma: Experience from the radiotherapy department at Mohammed-V military teaching hospital in Rabat (Morocco)]. / Plasmocytome solitaire osseux : expérience du service de radiothérapie de l'hôpital militaire d'instruction Mohammed-V de Rabat (Maroc).

PURPOSE: The primary objective was to determine in our department the progression-free survival rate of patients with solitary bone plasmocytoma and secondarily to evaluate its diagnostic, therapeutic and evolutionary aspects. PATIENTS AND METHODS: This is a retrospective review of 12 patients monitored and treated in the radiotherapy department of the Mohammed-V military medical teaching hospital in Rabat for a solitary bone plasmocytoma between January 2012 and December 2018. The average age of our patients were 53.8 years old (range: 31-72 years old). Pain was the most common telltale sign. The site of the lesions was spinal in four cases, iliac in four cases, mandibular, ribal, humeral and at the level of the astragalus in one case respectively. All patients received radiotherapy. This irradiation was delivered alone in 60% of cases or associated with surgery in 40% of cases. The average dose of radiotherapy was 47.3Gy (range: 45 to 50.4Gy) and this was delivered by a modulated volumetric arc therapy technique in ten patients and conformal tridimensional radiotherapy in two patients. RESULTS: Local control, defined by stability or radiological regression, was obtained in ten patients and four patients progressed to multiple myeloma, two of whom died. The average duration of follow-up was 51 months. CONCLUSION: Radiation therapy is the standard treatment for solitary bone plasmocytoma. It ensures good local control in 90% of cases. The prognosis is affected by progression to multiple myeloma, which justifies rigorous monitoring after treatment and suggests a reflection on the exact place of chemotherapy.

Radiotherapy of nasopharyngeal cancer using Rapidarc: dosimetric study of military teaching hospital Mohamed V, Morocco.

BACKGROUND: The aim of the present study is to assess efficacy and efficiency of Volumetric-modulated arc therapy (VMAT) technique in treatment of nasopharyngeal cancer in our institution and to report toxicity related to this technique. METHODS: Between June 2013 and January 2015, thirty-two patients with non metastatic nasopharyngeal cancer were curatively treated using VMAT Rapidarc. Dose prescription was performed using two different schedules, it consisted of either simultaneous integrated boost or simultaneous modulated accelerated radiation therapy delivering 70 Gy in 35 fractions and 69.96 in 33 fractions respectively. The choice was leaved at the discretion of the treating physician. The optimization process was performed by Eclipse software version 10.0 (Varian Medical Systems), using PRO algorithm (Progressive resolutive optimisation) version 3. Data was collected from dose-volume histograms for both planning target volumes (PTV) and organs at risk (OAR). We calculated the homogeneity index and the conformity index as well as the number of monitor units MU and the treatment delivery time. We also reported acute and late toxicity related to radiation therapy. RESULTS: For the PTV high risk (HR), intermediate risk (PTV IR) and low risk (LR) the D95% was 97.21 ± 1.5, 97.5 ± 3.3 and 97.10 ± 6.86 respectively. Whereas, The D5% was 104.6 ± 2.16, 103.8 ± 2.1 and 100.89 ± 7.26. The CI for PTV HR was 0.98 ± 0.02 and the HI was 0.08 ± 0.02. The mean treatment delivery time was 2.3 ± 0.2, and the mean MU number was 527.6 ± 131.4. Grade 4 toxicity was not reported in any case. Grade 3 xerostomia was observed in only 3(9.4%) patients and no patients developed grade 3 hearing loss. CONCLUSION: Our results confirmed the abilities of VMAT to provide excellent coverage of target volumes while sparing OAR especially the nervous structures and salivary glands.

Radiotherapy on hidradenocarcinoma.

CONTEXT: Clear cell Hidradenocarcinoma is a rare carcinoma arising from sweat glands. It is an aggressive tumor that most metastasizes to regional lymph nodes and distant viscera; surgery with safe margins is the mainstay of treatment. CASE REPORT: We report a case of 68-year-old woman who presented with an invasive clear cell hidradenocarcinoma situated in the left parotid area which recurred 5 months after surgery, this recurrence was managed successfully by high-dose irradiation of the tumor bed (66 Gy) and regional lymphatic chains (50 Gy), after a follow-up of more than 15 months, the patient is in good local control without significant toxicity. CONCLUSION: POST OPERATIVE RADIOTHERAPY ALLOWS BETTER LOCAL CONTROL AND SHOULD BE MANDATORY WHEN HISTOLOGICAL FEATURES PREDICTIVE OF RECURRENCE ARE PRESENT: positive margins, histology poorly differentiated, perineural invasion, vascular and lymphatic invasion, lymph node involvement, and extracapsular spread.