This chapter is in memory of his work and his devotion to patient care.
Born in England in 1959, emigrated to Israel in 1970.
Trained at the Hebrew University School of Medicine (class of 1982).
Following his military service, he specialized in Internal Medicine (1988-1992), followed by a clinical fellowship in Hematology (1992-1994).
After completing his clinical training he spent 2 years (1994-1996) at the Furie lab (New England Medical Center) in Boston doing basic research in coagulation, focusing in particular on the function of the gamma carboxyglutamic acid-rich (GLA) domain of the clotting factor IX.
Since returning to Israel, he has continued basic and clinical research in coagulation, especially investigating hypercoagulable states, as well as performing clinical research concentrating on acute myeloid leukemia (AML).
Medical Interests
Treatment of Leukemia Patients
1. The optimal treatment of AML – In this field Dr. Gillis was instrumental in organising the third Israel national protocol in 1993, and the fourth Israel national protocol in 1997. The latter protocol was novel in combining idarubicin, etoposide and cytosine arabinoside in the induction regimen. In a multi-center national study fifty patients were enrolled and the results are currently being analyzed in preparation for publication.
2. Prevention and treatment of infectious complications in AML patients – Our department pioneered the policy of selectively discharging afebrile AML patients during chemotherapy induced neutropenia. This was considered novel when published in the American Journal of Hematology in 1995, but is standard practice today at many institutions.
Dr. Gillis is an investigator in the EORTC study XIV which is examining the addition of vancomycin in severe prolonged febrile neutropenia (in collaboration with Prof. Mervyn Shapira of the department of Clinical Microbiology). We have also collected data on the use of peripherally inserted central catheters (PICC-lines) in AML patients. Our impressive results, which stimulated great interest when presented at the American Society of Hematology meeting in New Orleans (December 1999) have recently been accepted for publication.
3. Hairy Cell Leukemia (HCL) – HCL is an uncommon indolent B-cell disorder, usually presenting with “hairy” lymphocytes, splenomegaly and pancytopenia. Standard chemotherapy is ineffective, and patients have usually been referred for splenectomy or received interferon. At Hadassah we were the first in Israel (and one of the first in Europe) to have access to 2-chlorodeoxyadenosine (2-CDA) for the treatment of this disorder. This agent is remarkable in that a single 7 day course induces complete remission in approximately 90% of patients treated, with 75% remaining in prolonged remission. We summarised our experience in more than 20 patients in 1994, and continue to treat more patients even though the drug is now widely available in Israel and abroad. Recently, we noticed that several patients who were in long-term remission had severely hypoplastic / aplastic foci in their routine follow up bone marrow biopsies. This prompted us to review all available biopsies in our patients to assess the incidence and significance of this observation. We reviewed 94 biopsies in 31 patients and concluded that this is a relatively common finding, probably caused by 2-CDA. Interestingly, most patients had normal complete blood counts, suggesting that normal hematopoiesis takes place at other, unusual sites. The long-term clinical significance is unknown since the longest follow-up is only 7 years. However, this finding is worrisome since it theoretically may progress to aplastic anemia or myelodysplasia. Therefore, we have reported this histopathological finding and plan to continue to follow our patients indefinitely.
Basic Science Research Projects
1. The role of PAI-1 inhibitors in preventing bleomycin-induced pulmonary injury. Bleomycin is an effective chemotherapeutic agent, however its use is severely limited by its toxic effect on the lungs. Developing a method to prevent pulmonary injury in patients receiving this drug would allow us to give much higher doses and would be beneficial in the treatment of many malignant diseases, especially lymphoma. Bleomycin-induced lung injury in mice is also a popular model for idiopathic pulmonary fibrosis (IPF). Preliminary evidence points to a role for the coagulation system in the pathophysiology of the lung injury. In this project we are using specific inhibitors of various parts of the fibrinolytic system to try and elucidate the exact mechanism. We hope to be able to proceed from these studies to clinical trials in patients with resistant malignancies or with IPF.
2. Investigating the hypercoagulable state in thalassemia. It is now well-established that thalassemia major is a hypercoagulable state. The exact mechanism has been under study for several years. Possible explanations include pathological exposure of procoagulant phospholipids on the outer membrane of the thalassemic erythrocyte, activated platelets and low levels of natural anticoagulants (especially Protein S). We are investigating a novel mechanism – the possible role of the monocyte in the hypercoagulable state. Preliminary results are encouraging and suggest that this might be a fruitful area for pharmacological intervention, not only in thalassemia, but also in other common diseases in which monocytes play a role in the thrombotic process.