Israel Medical Association Journal

Background: HER2 is an important prognostic and predictive marker in invasive breast cancer. It is currently assessed by immunohistochemistry for protein over-expression and by fluorescence in situ hybridization for gene amplification. The immunohistochemistry-equivocal cases (2+) are currently retested by FISH[1] to determine eligibility for trastuzumab treatment. Retesting by FISH significantly raises the cost of patient management and sometimes delays treatment. The 4B5 is a new, FDA-approved, rabbit monoclonal antibody for HER2 testing.

Objectives: To examine the reliability of 4B5 IHC[2] HER2 testing in cases found to be HER2 status equivocal by CB11 IHC.

Methods: Twenty-eight invasive breast cancer cases, with an equivocal HER2 status by CB11 IHC, were retested by the 4B5 antibody as well as by FISH analysis. The scoring was performed using the same guidelines as HercepTest and was correlated with the FISH ratio. Results: Of the original 28 CB11 clone designated equivocal cases, 14 (50%) showed negative HER2 staining using the 4B5 clone (HercepTest score 0 and 1+). Five cases (18%) proved to be positive (HercepTest score 3+) and 9 cases (32%) remained equivocal (HercepTest score 2+). The corresponding FISH ratio results showed that all 4B5 negative cases were negative by FISH testing, with a negative predictive value of 100% 4 of 5 of the 4B5-positive cases were positive by FISH testing, with a positive predictive value of 80%. One 4B5-positive case was borderline-high (2.2 ratio) by FISH. The correlation between 4B5 IHC and FISH was statistically significant (P = 0.0013) by chi-square test.

Conclusions: Sequential testing by 4B5 IHC could greatly reduce the need for FISH testing in cases considered HER2 equivocal by CB11 IHC.
 

 
[1] FISH = fluorescence in situ hybridization

[2] IHC = immunohistochemistry

Background: An accurate preoperative definition of tumor and lymph node status is needed for reaching the correct decision regarding rectal cancer treatment. Transrectal ultrasonography is the most commonly used diagnostic modality for the local staging of rectal cancer.

Objectives: To determine the accuracy of TRUS[1] in the staging of rectal cancer.

Methods: We conducted a retrospective study on 95 patients evaluated by TRUS. The rectum was subdivided into two parts (lower and upper).

Results: Sixty patients underwent radical surgery. Of these, 34 received no preoperative chemo-irradiation owing to µT1, µT2 tumor or the patient’s choice (neo-adjuvant treatment was suggested to patients with adenocarcinoma that proved to be µT3). The overall accuracy rate was 80% for T stage. Overstaging was found in 13.3% and understaging in 6.7%.The N-stage was correctly assessed in 70%. The overall accuracy rate for tumors was 73.9% in the lower part and 90.9% in the upper. A trend towards a lower accuracy rate for low-lying tumors compared to high-located rectal tumors was found (P = 0.532), which did not reach statistical significance.

Conclusions: TRUS gave better results for T1 and T3 stage rectal tumors but was inaccurate for stage T2, indicating the possible need for local excision in order to base the final treatment for T2 tumors on pathologic staging.
[1] TRUS = transrectal ultrasonography
 

Background: Cancer is a leading cause of mortality worldwide. The most effective way to combat cancer is by prevention and early detection.

Objectives: To evaluate the outcome of screening an asymptomatic population for the presence of benign and neoplastic lesions.

Methods: Routine screening tests for prevention and/or early detection of 11 common cancers were conducted in 300 consecutive asymptomatic, apparently healthy adults, aged 25–77 years. Other tests were performed as indicated.

Results: Malignant and benign lesions were found in 3.3% and 5% of the screenees, respectively, compared to 1.7% in the general population. The most common lesions were in the gastrointestinal tract followed by skin, urogenital tract and breast. Advanced age and a family history of a malignancy were associated with increased risk for cancer with an odds ratio of 9 and 3.5, respectively (95% confidence interval 1.1–71 and 0.9–13, respectively). Moreover, high serum C-reactive protein levels and polymorphisms in the APC and CD24 genes indicated high cancer risk. When two of the polymorphisms existed in an individual, the risk for a malignant lesion was extremely high (23.1%; OR[1] 14, 95% CI[2] 2.5–78).

Conclusions: Screening asymptomatic subjects identifies a significant number of neoplastic lesions at an early stage. Incorporating data on genetic polymorphisms in the APC and CD24 genes can further identify individuals who are at increased risk for cancer. Cancer can be prevented and/or diagnosed at an early stage using the screening facilities of a multidisciplinary outpatient clinic.

Pancreatic cancer is not a common malignancy in Israel, but it is the third most common cause of cancer mortality, attributable to a lack of screening tests, inaccessibility of the pancreas, and late cancer stage at diagnosis. We reviewed the epidemiology, known risk factors and screening methods available in Israel and describe the Israeli national consortium that was established to identify persons at risk and decide on screening methods to detect and treat their early-stage pancreatic cancer. In collaboration with the Israel National Cancer Registry, we evaluated the incidence and trends of the disease in the Jewish and non-Jewish populations. The consortium reviewed known lifestyle risk habits and genetic causes, screening methodologies used and available in Israel. Overall, there are about 600 new patients per year, with the highest incidence occurring in Jewish men of European birth (age-standardized rate 8.11/10⁵ for 2003–06). The 5 year survival is about 5%. The consortium concluded that screening will be based on endoscopic ultrasonography. Pancreatic cancer patients and families at risk will be enrolled, demographic and lifestyle data collected and a cancer pedigree generated. Risk factors will be identified and genetic tests performed as required. This concerted national program to identify persons at risk, recommend which environmental risk factors to avoid and treat, and perform endoscopic ultrasound and genetic screening where appropriate, might reduce their incidence of invasive pancreatic cancer and/or improve its prognosis

Background: The role of endoscopic ultrasound in evaluating the response of esophageal cancer to neoadjuvant chemotherapy is controversial.

Objectives: To evaluate the accuracy of EUS[1] in restaging patients who underwent NAC[2].

Methods: The disease stage of patients with esophageal cancer was established by means of the TNM classification system. The initial staging was determined by chest and abdominal computed tomography and EUS. Patients who needed NAC underwent a preoperative regimen consisting of cisplatin and fluouracil. Upon completion of the chemotherapy, patients were restaged and then underwent esophagectomy. The results of the EUS staging were compared with the results of the surgical pathology staging. This comparison was done in two groups of patients: the study group (all patients who received NAC) and the control group (all patients who underwent primary esophagectomy without NAC).

Results: NAC was conducted in 20 patients with initial stage IIB and III carcinoma of the esophagus (study group). Post-chemotherapy EUS accurately predicted the surgical pathology stage in 6 patients (30%). Pathological down-staging was noted in 8 patients (40%). However, the EUS was able to observe it in only 2 patients (25%). The accuracy of EUS in determining the T status alone was 80%. The accuracy for N status alone was 35%. In 65% of examinations the EUS either overestimated (35%) or underestimated (30%) the N status. Thirteen patients with initial stage I-IIA underwent primary esophagectomy after the initial staging (control group). EUS accurately predicted the surgical pathology disease stage in 11 patients (85%).

Conclusions: EUS is an accurate modality for initial staging of esophageal carcinoma. However, it is not a reliable tool for restaging esophageal cancer after NAC and it cannot predict response to chemotherapy.

Background: Gastrointestinal stromal tumors are the most common mesenchymal neoplasms of the human gastrointestinal tract.

Objectives: To review our accumulated experience using surgery to treat gastrointestinal stromal tumors.

Methods: We reviewed all patient charts and histological diagnoses of leiomyomas, leiomyosarcomas, leiomyoblastomas and schwannomas. Only tumors that displayed c-kit (CD117) immunopositivity were defined as GISTs[1].

Results: The study group comprised 40 female and 53 male patients (age 26–89 years); 40.9% of the tumors were classified as malignant, 39.8% as benign, and 19.4% as of uncertain malignancy. Fifty-six GISTs were located in the stomach (60.2%), 29 in the small bowel (31.2%), 4 in the duodenum (4.3%), 2 in the colon (2.1%) and 2 in the rectum (2.1%). Incidental GISTs were found in 23.7% of our patients. Mean overall survival time for malignant gastric GISTs was 102.6 months (95% confidence interval 74.2–131.1) as compared to 61.4 months mean overall survival for malignant small bowel GISTs (95% CI[2] 35.7–87) (P = 0.262). The mean disease-free survival period for patients with malignant gastric GISTs was 97.5 months (95% CI 69.7–125.2) as compared to only 49.6 months (95% CI 27.4–71.7) for patients with small bowel malignant GISTs (P = 0.041).

Conclusions: We found a high percentage of incidental GISTs. Gastric GISTs are more common than small bowel GISTs. Patients with malignant gastric GISTs have a significantly better prognosis than patients with malignant small bowel GISTs. A statistically significant correlation was found between age and malignant potential of the GIST.

Background: Dedicated, organ-specific screening clinics have been shown to significantly reduce cancer morbidity and mortality.

Objectives: To establish a dedicated clinic for Clalit Health Service patients at high risk for hereditary gastrointestinal cancer and to provide them with clinical and genetic counseling, diagnostic screening and follow–up.

Results: During the 3 years of the clinic's activity, 634 high risk families, including 3804 at-risk relatives, were evaluated. The most common conditions were hereditary colorectal syndromes, Lynch syndrome (n=259), undefined young-onset or familial colorectal cancer (n=214), familial adenomatous polyposis (n=55), and others (n=106). They entered follow-up protocols and 52 underwent surgical procedures.

Conclusions: Consistent public and professional education is needed to increase awareness of hereditary colorectal cancer and the possibility of family screening, early diagnosis and therapy. The public health services – i.e., the four health management organizations – should provide genetic testing for these patients who, at present, are required to pay for almost all of these available but costly tests. Dedicated colorectal surgical units are needed to provide the specialized therapeutic procedures needed by patients with familial colorectal cancer. Our future plans include adding psychosocial support for these at-risk patients and their families as well as preventive lifestyle and dietary intervention. 

Background: Computed tomographic colonography, also known as virtual colonoscopy, is a rapid, non-invasive imaging technique for the detection of colorectal masses and polyps that is becoming increasingly popular.

Objectives: To evaluate the availability, technique, standards of performance and indications for CT colonography in Israel.

Methods: A questionnaire on CT colonography was sent to all radiology departments and private institutions that perform CTC[1] in Israel. We evaluated multiple technical parameters regarding the performance and interpretation of CTC as well as radiologists' training and experience.

Results: Fourteen institutions – 7 hospitals and 7 private clinics – participated in the study. Most of the small radiology departments and nearly all of the more peripheral radiology departments do not perform CTC studies. Since 2000 and until March 2007, a total of 15,165 CTC studies were performed but only 14% (2123 examinations) were performed at public hospitals and 86% (13,042 exams) at private clinics. CTC was performed after an incomplete colonoscopy or for various contraindications to endoscopic colonoscopy in up to a third of cases. In the various institutions patients were self-referred in 20–60% of cases, more commonly in private clinics. All CTC examinations were performed on 16–64 slice CT scanners and only a small minority was performed on 4-slice scanners in 2001. All but one center used low radiation protocols. Nearly all facilities used a 2 day bowel-cleansing protocol. All except one facility did not use stool tagging or computer-aided diagnosis. All facilities inflated the colon with room air manually. All institutions used state-of-the-art workstations, 3D and endoluminal navigation, and coronal multi-planar reconstructions routinely. There are 18 radiologists in the country who perform and interpret CTC studies; half of them trained abroad. Ten of the radiologists (56%) have read more than 500 CTC studies.

Conclusions: In Israel, CTC examinations are performed by well-trained and highly experienced radiologists using the latest CT scanners and workstations and adhering to acceptable CTC guidelines.