[Neuroendocrine carcinoma of the digestive tract: a literature review]

Neuroendocrine carcinoma is a rare and agressive malignant tumor, mainly developing at the expense of the respiratory and of the digestive tract. Among the digestive tract, appendix, small bowel, and pancreas are the preferential sites of involvement, other locations have been more rarely reported. Neuroendocrine digestive tumors may present with various symptoms in relationship with their localization and a complex pathophysiology. Diagnosis is often made at an advanced stage, explaining partly the bad prognosis of these tumors. The optimal management of digestive neuroendocrine tumors is rendered difficult by their rarity and by a low number of randomized trials. We review the literature regarding epidemiologic and prognostic features of these rare tumors, their diagnostic and therapeutic care. Potential complications are also discussed.

[Positron emission tomography in the management of cervix cancer patients]

Since its introduction in clinical practice in the 1990's, positron emission tomography (PET), usually with (18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG), has become an important imaging modality in patients with cancer. For cervix carcinoma, FDG-PET is significantly more accurate than computed tomography (CT) and is recommended for loco-regional lymph node and extrapelvic staging. The metabolic dimension of the technique provides additional prognostic information. Ongoing studies now concentrate on more advanced clinical applications, such as the planning of radiotherapy, the response evaluation after the induction of therapy, the early detection of recurrence. Technical innovations, such as PET cameras with better spatial resolution and hybrid positron emission tomography/computed tomography (PET-CT), available now on the whole territory, provide both anatomic and metabolic information in the same procedure. From the point of view of biological metabolism, new radiopharmaceutical probes are being developed. Those hold promise for future refinements in this field. This article reviews the current applications of FDG-PET in patients with cervix cancer.

The use of computed tomography in radiotherapy treatment planning for breast cancer. How does conventional radiotherapy planning compare with virtual?

PURPOSE

To compare, in terms of ballistics and dosimetry, a conventional and a virtual simulation in 14 patients without changing the set-up.

PATIENTS AND METHODS

14 women with breast cancer were treated with postoperative radiotherapy from October 2003 to November 2004. Whole breast irradiation alone was indicated (50 Gy at International Committee on Radiation Units [ICRU] point in 25 fractions over 5 weeks) with, in some cases, an additional boost of 16 Gy to the tumor bed--that was not taken into account in this study. After CT scan, tangential fields were conventionally simulated using a Mecaserto Phebus-type simulator-CT scan. The planning target volume (PTV) was the clinical target volume (CTV) expanded with an additional margin of 1 cm in all directions but towards the skin. Both the lungs and the heart were delineated as organs at risk. Dosimetries were computed for the two beams arrangements i.e. 2D conventional and 3D virtual.

RESULTS

The mean age of 14 women was 51.4 years (range 26-65). Laterality was the left breast for 6 patients and the right for 8. Few differences were noticeable in terms of gantry angles. The 3D medial fields were more medial with a mean of 8 mm (range 0-15). The 3D lateral fields were more posterior with a mean difference of 8 mm (range 0-25). The dosimetry analysis showed that, with regard to conventional simulations, at least 95% of the CTV received in all cases > 95% of the prescribed dose. However, in 8 out of 14 patients (57%), 15% of the PTV received < 95% of the prescribed dose. The ICRU 50 quality criterion that at least 95% of the PTV (PTV(95%)) should receive at least 95% of the prescribed dose was never met with conventional simulation. In the case of virtual simulation, the ballistics of the treatment were designed to meet the ICRU quality criterion and thus the PTV95% was higher here than with the conventional simulation by a mean of 17.6% +/- 9.7%. The percentage of CTV receiving a dose higher than 107% of the prescribed dose was 21.3% +/- 12% with conventional and 24% +/- 11% with virtual simulation.

CONCLUSION

The high incidence of breast cancer, the essential role of radiotherapy in its treatment and the potential ensuing toxicity explain why so many studies are devoted to the improvements brought to the techniques of this treatment. The virtual planning of the treatment, however, comes up against many difficulties. The countering of the CTV is complex and necessitates a combination of clinical examination and imagery. The choice of margins around the CTV has not been standardised and is largely dependent both on the equipment used and the quality control methods.

[Cancer chemotherapy of the upper aerodigestive tract]

Tumours of the upper aerodigestive tract represent the sixth most frequent kind of cancer in France and throughout the world. If the localised forms may be controlled in the long run in two thirds of cases by surgery or radiotherapy, only one third of locally advanced forms are accessible to a cure after association from radiotherapy and chemotherapy. Besides, with a median of survival less than six months, metastatic tumours present a catastrophic spontaneous prognosis among patients with a medical ground that is often heavily deteriorated by prolonged exposure to alcohol and tobacco. Thus, there is a necessity to implement adapted therapeutic strategies to each patient and based on satisfactory proof levels of effectiveness. Optimisation of existing chemotherapy protocols and development of new therapies, in particular of targeted therapies, remain an important objective in the hope to improve results of treatments in locally advanced and metastatic cancers of the oral cavity.

[Favorable outcome of gemcitabine-induced acute respiratory distress syndrome]

Gemcitabine is a new important drug used to treat solid tumors including non-small cell lung cancer, pancreatic, bladder and breast cancers. Myelosuppression is the most common adverse effect. Pulmonary toxicity is rare and usually mild and self-limiting with acute dyspnea. Severe pneumonitis and potentially fatal acute respiratory distress syndrome (ARDS) have been described in patients treated for a non-small cell lung cancer. We report a case of gemcitabine-induced ARDS in a 72-year old patient treated with gemcitabine and cisplatin for a bladder cancer without lung metastasis. Administration of high doses of corticosteroids led to a prompt symptomatic improvement.

Comparaison simulation classique–simulation virtuelle au cours d'une irradiation mammaire : étude prospective sur 14 patientes

PURPOSE

To compare conventional 2D simulation and virtual simulation on 14 patients with breast cancer.

PATIENTS AND METHODS

Patients were simulated for treatment using standard procedure. They subsequently underwent CT scan in the treatment position. The CTV was defined as breast tissue. The PTV was obtained by adding a 3D margin of 1 cm around CTV. Organs at risk (lungs and heart) were outlined. Ballistics and dose distribution obtained with the two planning methods were compared.

RESULTS

With conventional simulation, 95% of CTV received 95% of the dose prescribed. Virtual simulation significantly improved dosimetric coverage of PTV without increasing irradiation volume of lung and heart. In 2D simulation, using three slices allowed optimisation by adjusting wedge angle. The five-slice plan was a much better predictor of the maximum dose regions when compared to the three-slice plan. Using entire CT data didn't give any benefit.

CONCLUSION

Variations in CTV delineation and PTV definition limit interest of virtual simulation. In classic simulation, a 5 CT slice-plan can be used to optimise dose distribution.

Intérêt de la chimiothérapie néoadjuvante dans le traitement des séminomes purs intracérébraux : expérience de l'hôpital du Val-de-Grâce

Optimal management of intracranial germinomas remains controversial. Focal irradiation to the primary tumor followed by prophylactic craniospinal radiotherapy represents the traditional treatment resulting in excellent long-term survival but potential late effects. To decrease late effects related to extensive fields of radiotherapy, combined chemotherapy and irradiation has been tested with reduced volumes and doses of radiation therapy. We report our experience about four patients successfully treated by neoadjuvant chemotherapy with carboplatin and etoposide followed by radiotherapy delivering 26 to 36 Gy to the whole brain and 36 to 50 Gy to the initial tumor volume.

Radiation injuries of the gastrointestinal tract in Hodgkin's disease: the role of exploratory laparotomy and fractionation. A study of 19 cases observed in a series of 134 patients treated at the Institut Gustave Roussy from 1972 to 1982

Out of 134 patients irradiated below the diaphragm to a dose of 40 Gy for Hodgkin's disease at the Institut Gustave-Roussy, 19 (14%) were subsequently found to present with radiation injuries of the gastrointestinal tract. Since five patients presented with two different injuries, 24 radiolesions were observed. Most of them (17 out of 24) were gastric or duodenal. Twelve (out of 24) were ulcers. Nine patients required surgery. A complete cure of the radiation injuries was obtained in 15 out of 19 patients. Sex, age, stage, histology or initial chemotherapy were not found to play a role in the occurrence of radiation damage. On the contrary, the role of a previous exploratory laparotomy appeared important; for the patients who underwent laparotomy and irradiation, the complication rate was 23%. For the patients treated by irradiation alone, the complication rate was 7% (p less than 0.01). Fractionation was found to be another important parameter: for 52 patients treated using 3 weekly fractions of 3.3 Gy, the complication rate was 25%, compared to 8% (p less than 0.01) for 76 patients treated using 4 weekly fractions of 2.5 Gy. Combining these two factors, we found a 42% complication rate for the group of patients who underwent laparotomy and who were treated by means of 3 fractions of 3.3 Gy per week, whereas patients irradiated using 4 weekly fractions of 2.5 Gy, without any previous laparotomy, had only a 5% complication risk (p less than 0.001).