Page 3 - CanTalk Issue 73 Autumn 2015
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CANTALK 73 AUTUMN 2015  CANCER SOCIETY OF NEW ZEALAND • Te Kāhui Matepukupuku o Aotearoa

Chronic lymphocytic leukaemia–                                                                        Dr Robert Weinkove
a change in the air                                                                                       MA MBBS FRCPath PhD
                                                                                                          Consultant Haematologist,
Despite its dramatic-sounding name, chronic                                                               Wellington Blood &
lymphocytic leukaemia (CLL) is not always a life-                                                         Cancer Centre, CCDHB
changing diagnosis. Small abnormal populations
(‘clones’) of white blood cells can be found in the       Rituximab is a specifically-designed medicine which,
blood of 7 percent of healthy people above 65 years of    when given through the veins, latches onto the leukaemia
age, and once these clones reach a certain arbitrary      cells, labelling them for destruction by the patient’s own
level, the person is said to have CLL. Because it is      immune system. When added to chemotherapy, rituximab
increasingly common for doctors to request routine        leads to improved response rates and longer survival for
blood tests, many people are given a diagnosis of CLL     people with CLL. Although the CLL will relapse eventually,
many years before they develop any symptoms of the        most people will have a remission of at least 3 years after
disease. This is ‘early-stage’ CLL.                       receiving rituximab in combination with chemotherapy.
                                                          More recently, a second antibody treatment called
We call CLL an ‘indolent’ condition, meaning that it      obinutuzumab was licensed in New Zealand for older
typically progresses slowly, not rapidly, over time.      people with CLL, to be given in combination with a tablet
The usual pattern is a gradual increase in white blood    chemotherapy. A funding decision for obinutuzumab is
count over many years. On average, it takes longer        awaited.
than 12 years before someone with early-stage CLL
develops symptoms and needs treatment. Indeed,            Looking ahead, a series of new medicines seem to be
early-stage CLL can be safely monitored in primary        very effective for CLL, based on the results of recent
care, with an annual blood test and review by a           clinical trials. These are tablet-based treatments, which
general practitioner.                                     work by interfering with signalling pathways inside the
                                                          leukaemia cells. These medicines, such as ibrutinib,
Unfortunately, CLL does not always behave in such         idelalisib and venetoclax do not damage normal cells
a benign fashion. Some people’s CLL cells carry, or       in the same way that conventional chemotherapies do,
acquire, genetic alterations that make them grow          although each new drug has its own specific side effects.
more rapidly. In this case, the CLL is more likely to     Some New Zealanders have already received these new
cause symptoms, such as fevers or drenching night         medicines by taking part in clinical trials, or through a
sweats, shortness of breath due to anaemia, bruising      compassionate-access programme.
or bleeding due to low platelet counts, or bulky
enlargement of the lymph glands. If these problems        Together with the success of antibody treatments, the
occur, patients are referred to a haematologist, and      emergence of the new tablet medicines suggests we
treatment of the CLL may be recommended.                  may soon be able to treat CLL without using conventional
                                                          chemotherapy at all. Clinical trials are already underway
Ten years ago, the only treatments available for CLL      to compare combinations of antibodies and the new
in New Zealand were cytotoxic chemotherapies –            tablet medicines against conventional chemotherapy
medicines that act by damaging the genetic material       combinations. If these trials prove successful, cost of
within cells. Because malignant cells often grow          the new treatments will undoubtedly be a consideration.
quickly and lack repair mechanisms, they are more         On the positive side, at least five new tablet medicines
prone to the effects of chemotherapies than are           are in advanced clinical trials for CLL. This suggests
healthy cells in the body. Unfortunately, healthy cells   that pharmaceutical companies might compete on price,
still suffer to some extent, and this causes many of the  improving affordability. I hope that within five years we
side effects of conventional chemotherapies.              will be able to offer highly effective chemotherapy-free
                                                          treatment for New Zealanders with advanced-stage CLL. □
For the last few years, we have been adding an antibody
treatment called rituximab to routine CLL chemotherapy.   Dr Robert Weinkove

(below) Chronic lymphocytic leukaemia (CLL) – the
lymphocytes with the darkly staining nuclei and scant
cytoplasm are the CLL cells.

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