Issue No. 3 - Jan 2008

The number of recurring genetic abnormalities recognized in acute myeloid leukemia (AML) has increased rapidly in recent years and at present, acute leukemia is probably the most extensively analyzed human cancer. Combined cytogenetic and molecular genetic studies have revealed that clonal chromosome abnormalities are present in the majority of patients with AML that are very closely, and sometimes uniquely, associated with distinct subsets of leukemia. Detailed analysis of these rearrangements indicates that in most instances chromosome rearrangements result in gene fusions leading to chimeric abnormal protein with oncogenic potential. Continued identification and characterization of genes involved in the development of leukemia has a major impact on our understanding of the molecular biology of cancer and in formulating of biologically based therapies.

Proper Management of Cancer requires evaluation of tumor extent, monitoring of therapy and evaluation of treatment induced side effects. Imaging modalities are crucial in achieving this all the three main pre-requisites for this proper management. Structural modalities such as computerized tomography (CT) and functional modalities such as gamma camera imaging are complementary rather than competitive for cancer management. Each modality has advantages and limitations. Positron emission tomography (PET) as a recent functional modality is now the most powerful modality in advancing cancer management.

Functional Nuclear Medicine studies including PET provide useful information that cannot be obtained by morphologic modalities. Being a metabolic imaging modality using biologically important compounds with Carbon-11 (C-11) Fluorine-18 (F-18), it has the advantage of revealing biochemical parameters of lesions as glucose, oxygen or amino acid metabolism. It has also an outstanding spatial, contrast and temporal resolutions, and it provides accurate quantification and is cost effective as it helps avoid unnecessary diagnostic and therapeutic procedures. The PETCT combines anatomical and functional imaging and is considered the state-of-the-art imaging technique for the assessment of lymphoma and other malignancies.

Lymphoma is a common malignancy that is increasing over the last few decades. PET has an important role in the diagnosis, staging, early assessment of response to therapy, assessment of residual tumor after completion of therapy, detecting recurrence and providing prognostic information. Its role varies however based on the histological type of the tumor.

In this work a dosimetry study is presented in which the results of absorbed dose data determined under reference condition according to the IAEA TRS-398 protocol and the NCS report-2 are compared. The IAEA TRS-398 protocol for absorbed dose calibration is based on ionization chamber having an absorbed dose to water calibration factor ND,W, while the NCS- 2 report for absorbed dose calibration is based on an ionization chamber having an air- kerma calibration factor NK. This study shows that the absorbed dose calculated with the IAEA TRS- 398 formalisms is higher than that calculated with the NCS Report-2 formalism within a range of 0.4 to 0.9% in a cobalt-60 beam, and from 0.2 to 1.1% for photon beams of 6, 8 and 18 MV. The chambers used are PTW 30001, 30004, and NE-2571, which have calibration factors NK and ND,W traceable to the BIPM (Bureau International des Poids et Mesures).

Aim
To describe our technique in delivering post mastectomy radiotherapy to chest wall using electron-photon mixed beam with or without isocentric application of the tangential photon portals, and to evaluate the associated acute and delayed morbidities.

Patients and methods
Twenty-two females with invasive breast cancer were subjected to modified radical mastectomy with adequate axillary dissection. All the patients have either tumour > 5 cm and/ or positive axillary nodes >3. Chest wall was irradiated by a mixed beam of 6-Mev electrons (10Gy) and opposed tangential fields using 6 Mev-photons (36 Gy) followed by 6-Mev electrons boost to the scar of mastectomy for 4 Gy/2 fractions. We randomly allocated our patients to receive the photon beam with or without the isocentric technique.

Results
The mean dose to the planned target volume (PTV) by mixed beam was 44 Gy (96%) with a mean dose of 42 Gy (91%) to the overlying skin for the whole study group. In cases with right breast disease (17 cases), the mean right lung tissue volume within the PTV was 220 ml (15%). It was relatively higher with the noniscocentric technique, 281 ml (19%), compared to the isocentric technique of 159 ml (10.5%). In cases with left breast disease (5 cases), the mean left lung volume within the PTV was 175 ml (14%). Larger volume of the lung tissue was included with the non-isocentric technique, 197 ml (16%) compared to the isocentric technique of 153 ml (12%).The mean scattered doses to the rest of the lung tissue, the rest of the heart in left breast cases, and the contra-lateral breast for the whole study group were 2.8 Gy, 1.8 Gy, and 1.4 Gy respectively and was comparable in both treatment arms. None of the cases developed any element of acute radiation related pneumonitis. Delayed radiation induced pneumonitis was seen in 2 cases (18%), with the chest wall treated with radiation with the non-isocentric technique.

Conclusion
This study clearly demonstrated the utility of mixed beam in irradiating the chest wall after mastectomy with the dose prescription we proposed. An adequate homogeneous dose level was delivered to the chest wall. The treatment was administered with accepted level of both acute and delayed treatment related morbidity especially when the photons were delivered by the isocentric technique.

Objective
To evaluate hemoglobin (Hb) levels before and during radiotherapy and its role as a prognostic factor on treatment results of patients treated for cancer cervix.

Materials and Methods
One hundred and seven patients with cervical cancer were registered and managed at KCCC during 1995 – 1999. The pre-treatment and mid treatment Hb levels were found for 47 patients only. Follow-up was done for these cases aiming at evaluation the overall and diseasefree survival. Statistical analysis was done using SPSS statistical package version 10.0.

Results
The median age of patients were 45 and ranged between 26-80 years. Kuwaiti patients represented 21.3% of cases. The most common stage was Stage IIb representing 51.1% followed by IIIb representing 27.7%. Stage Ib and IIa represented 12.8%. About 89.4% were squamous cell carcinoma, while adenocarcinoma was 6.4%. Treatment outcome revealed 18 relapses (38.3%). Disease-free survival for cases with pre-treatment Hb level < 12 was 16.3%, while for those with Hb level > 12 g/dL it was 62.9%. The difference was statistically significant (P=0.02).

Conclusion
Patients with pre-treatment Hb < 12 g/dL

Aim of the study
To assess the tolerability, toxicity and efficacy of neo-adjuvant Docetaxel and Cisplatin (TC) followed by concurrent Cisplatin and radiotherapy (RT) in patients with locoregionally advanced nasopharyngeal carcinoma (NPC).

Patients and methods
Fourteen patients with locally advanced NPC received two cycles of Docetaxel (75 mg/m2 on days 1, and 21) and Cisplatin (75 mg/m2 on days 1, and 21) followed by 7 weeks of Cisplatin (40 mg/m2 weekly) and RT at 70 Gy in 2-Gy per fraction.

Results
Response to neo-adjuvant TC was as follows: 5 patients (36%) and 11 patients (79%) achieved partial remission (PR) in regional nodes and nasopharynx, respectively. Nine patients (64%) and 1 patient (7%) achieved complete remission (CR) in regional nodes and nasopharynx, respectively. At 6 weeks after RT, 12 patients (86%) achieved CR in regional nodes and nasopharynx, and 2 patients (14%) achieved partial response (PR) in regional nodes and nasopharynx. Neo-adjuvant TC was well tolerated. The most common acute toxicity of Cisplatin plus Docetaxel was grade 3-4 leucopenia (57%) and alopecia (43%). The most common acute toxicity of Cisplatin plus RT was grade 3-4 mucositis (64%). At median follow-up of 12 months, one distant and one loco-regional failure occurred.

Conclusions
Neo-adjuvant Docetaxel and Cisplatin (TC) followed by concurrent Cisplatin and radiotherapy (RT) in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) was feasible and resulted in excellent local tumour control with acceptable toxicity profile.

The photosensitizer 13²-hydroxy bacteriopheophorbide- a methyl ester (132 OH- BPME) is characterized by a high absorption coefficient at the far red wavelength 750 nm and a good singlet oxygen quantum yield.

Methods & Results:
The pharmacokinetics of 13²-OH- BPME were studied in ovarian carcinoma on mice after iv administration of 7.8 μmole/kg body weight at different incubation intervals. The accumulated dye was chemically extracted from selected tissues and the concentrations were measured by absorption spectroscopy. The parenchymatous organs (liver, spleen and kidney) showed maximum 13²- OH- BPME concentrations after 2 hours incubation (liver, spleen), and 4 hours post injection (kidney). A high uptake was detected in the lung with maximum concentration at 2 hours. The malignant tissue accumulated high 13²- OH- BPME concentrations between 2-12 hours post injection with peaking at 8 hours. The 13²- OH- BPME concentrations in muscle tissue, representing the normal tumour surroundings, and in the skin were very low.

Conclusion
The results of our study suggest that PDT using 13²-OH-BPME could be effective at 8h post injection, where the tumour 13²- OHBPME uptake is maximum and the muscle and skin uptake will be minimum.

Aim
The aim of this paper is to present the first published case of a high-risk gastrointestinal stromal tumour (GIST) in Kuwait.

Case presentation and intervention
A thirty-six-year old Egyptian male patient presented with central upper abdominal pain of five-month duration. Clinically, there was an approximately 10 cm × 8 cm diffuse, nontender, firm mass in the epigastrium. A tumour of the stomach wall was diagnosed. The mass was surgically excised. At laparotomy there was obvious peritoneal dissemination. Histopathological examination revealed a (GIST) of the omentum. Postoperatively the patient was advised to receive imatinib mesylate for a period of one year.

Conclusion
Despite significant advances in new chemotherapeutic drugs, radical surgery remains the only method offering a chance for long-term survival. Although further data are required to evaluate its use in the adjuvant and neoadjuvant settings, imatinib mesylate currently provides the most effective treatment option in the management of advanced GIST.

Gastrosplenic fistula resulting from erosion of a primary splenic lymphoma is a very rare cause of massive upper gastrointestinal hemorrhage as compared to benign peptic ulcer disease, gastric Crohn’s disease, gastric adenocarcinoma, and primary gastric and splenic lymphomas. This hemorrhage can be successfully managed by splenic artery embolization, followed by splenectomy and gastric resection. A 50-year-old patient developed a gastrosplenic fistula during a course of chemotherapy for differentiated histiocytic lymphoma. The fistula was demonstrated by CT scan with oral contrast. The fistula was followed endoscopically and noted to have closed spontaneously with confirmed closure at laparotomy. The clinical management of this complication is discussed, and the literature pertaining to this rare condition is reviewed.