Adjuvant radiation therapy for malignant Abrikossoff's tumor: a case report about a femoral triangle localisation.

BACKGROUND: Granular cell or Abrikossoff's tumors are usually benign however rare malignant forms concern 1 to 3% of cases reported. Pelvic locations are exceptional. CASE PRESENTATION: We report a case of a 43-years-old patient who had a benign Abrikossoff's tumor localized in the right femoral triangle diagnosed at the biopsy. The patient underwent a surgical tumorectomy and inguinal lymph nodes resection. Histologically, the tumor showed enough criteria to give diagnosis of malignancy: nuclear pleomorphism, tumor cell spindling, vesicular nuclei with large nucleoli. Moreover, five lymph nodes were metastatic. Immunohistochemistry findings confirmed the diagnosis of granular cell tumor which is positive for S100 protein and CD68 antibodies. The mitotic index was nevertheless low with a Ki67 labeling index of 1-2%. A large surgical revision with an inguinal curage following radiotherapy were decided on oncology committee. Adjuvant radiotherapy on the tumor bed and right inguinal area of ​​50 Gy in conventional fractionation was delivered with the aim of reducing local recurrence risk. There was no recurrence on longer follow-up (10 months post radiotherapy). CONCLUSIONS: Adjuvant radiotherapy seems an appropriate therapeutic approach, even if controversial, given that some authors report effectiveness on local disease progression.

[Multicenter study on dose escalation with conformal and conventional radiotherapy for the treatment of localized prostatic cancer. Preliminary results of tolerance and quality of life]. / Etude multicentrique d'escalade de dose par radiothérapie conformationnelle pour le traitement du cancer localisé de la prostate. Résultats préliminaires de la tolérance et de la qualité de vie.

OBJECTIVE: To study the safety of conformal radiotherapy dose escalation up to 80 Gy for curative treatment of prostate cancer. MATERIAL AND METHODS: A multicentre trial sponsored by the PHRC include 164 patients under the age of 75 years with stage T1b-T3 N0 M0 prostatic adenocarcinoma, between 1995 and 1998. The prostate was treated at 5 dose levels: 18 patients at 66 Gy, 28 at 70 Gy, 49 at 74 Gy, 48 at 78 Gy, 21 at 80 Gy. The acute and delayed toxicity was graded according to a multidisciplinary glossary. Quality of life was evaluated before and one year after treatment using the EORTC QLQ-C30 questionnaire and additional questions. RESULTS: 89% and 55% of mild or moderate gastrointestinal and urinary adverse effects were observed during treatment, respectively. At long-term follow-up, of the 162 evaluable patients, 12.3% presented grade 2 adverse effects and 2.5% presented grade 3 adverse effects (1 case of haematuria, 2 urethral strictures, 1 bladder neck lesion) with no significant difference between the various dose levels. Two successive quality of life questionnaires were available for 119 patients: tiredness, pain and dyspnoea increased in parallel, but non-significantly in the groups receiving conventional doses or high doses. The proportion of patients reporting sexual activity without endocrine therapy decreased from 48% before treatment to 35% one year later. The proportion of patients with no clinical or laboratory signs of progression was higher in the high-dose group. CONCLUSION: No significant difference was observed between conventional dose levels and high dose levels in terms of toxicity or quality of life. As the adverse effects were acceptable, a randomized trial comparing 70 Gy and 80 Gy has been initiated.

Dose escalation with 3D-CRT in prostate cancer: French study of dose escalation with conformal 3D radiotherapy in prostate cancer-preliminary results.

PURPOSE: To evaluate the feasibility of dose escalation in a multi-institutional study in prostate cancer patients. METHODS AND MATERIALS: Between October 1995 and October 1998, 164 patients with localized adenocarcinoma of the prostate were treated with 3-dimensional conformal radiotherapy at one of five French institutions. The dose of radiation was escalated from 66 to 80 Gy (ICRU point). The maximum dose to the rectal wall was limited to 75 Gy. RESULTS: Results were compared in two groups, one (group 1) receiving the standard dose (n = 46 patients; 66 to 70 Gy) and the other (group 2) receiving the escalated dose (n = 118 patients; 74 to 80 Gy). There was no difference in the characteristics of patients between the two groups. The mean follow-up time was 32 months in group 1 and 17.5 months in group 2. No statistical difference between the two groups was observed in the incidence of late gastrointestinal and urinary toxicities. The probability of achieving a posttreatment prostate-specific antigen nadir of

[Comparative dosimetry study of two methods of intensity modulation performed on the same accelerator]. / Etude comparative dosimétrique de deux méthodes de modulation d'intensité réalisées sur le même accélérateur.

Intensity modulated radiation therapy (IMRT) is an advanced method of conformal radiotherapy. It permits optimal dose distribution to the target volume while preserving surrounding normal tissues. IMRT, with a multileaf collimator, can be realised in two different ways: either the segmented mode, which consists of combining small elementary static field, or the dynamic mode, which consists of moving the leaves while irradiating. The purpose of this work was to study these two methods of modulation on a Varian linear accelerator equipped with a collimator consisting of 40 pairs of one-centimetre-wide leaves. The measurements, obtained by using a diode array, showed that the quality of the irradiation in the dynamic mode does not depend on either the dose rate or the duration of the irradiation. In the segmented mode, weak magnitude segments are preferable, but increase the errors in the delivered dose. Comparisons of various profiles showed that the measured profiles are consistent with those programmed. Both modes seem to be equivalent for step-shaped profiles. In the case of profiles with constant slope, the segmentation generated by the segmented method deteriorates the profile. Even though the choice of technique is strongly dependent on the material available, the dynamic mode presents greater flexibility of use and has been chosen in our institution for IMRT.