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Chemotherapy is the standard treatment for inoperable pancreatic cancers
On the bright side , her treatment was discontinued because the tumour had become dormant , although her doctor had no clue why .
Chemotherapy is also used against locally advanced cancers to shrink them to a point where they can be safely taken out with surgery . In such cases , doctors aim to “ move the tumour away from the blood vessels so that they can go ahead and do a successful surgery , � explained Dr Manji .
But this approach doesn ’ t always work , as Luna ’ s experience demonstrates . She received chemotherapy from 2002 , when she was first diagnosed with a locally advanced cancer , until 2018 to keep the tumour at bay and make it amenable to surgery but to no avail . “ It seems that when it does shrink , it shrinks more back into the area of the blood vessels than away from them , so it ’ s been a difficult situation , � she said .
On the bright side , her treatment was discontinued because the tumour had become dormant , although her doctor had no clue why . �It ’ s been a nice break not to have chemo , though the side effects still last , like a tingling sensation in the hands and memory issues . � To cope with that , she has had to readjust her habits .
“ It ’ s hard to deal with simple things sometimes , you can put something down and not remember where you put it , � she explained . �I misplace things a lot , so I have just a general place to put everything so I know I have to go there when I ’ m looking for something . �
Overall , chemotherapy can achieve modest treatment outcomes against pancreatic cancers when compared to other malignancies . For instance , �breast and colon cancers are more likely to respond to chemotherapy than pancreatic cancers , � said Dr �ee . One hypothesis to make sense of this difference holds that there are few blood vessels running through pancreatic tumours , providing limited avenues for drugs to reach and kill off cancer cells . Chemo medications are delivered through the bloodstream and “ if they don ’ t get where we want them to get , then they ’ re less likely to be impactful , � he argued .
Despite their limited efficacy , chemotherapeutic drugs are still the only medications available for the vast majority of patients with pancreatic cancer , further evidence of the limited progress in the field .
This is in contrast to the effective but easier-totolerate alternatives to chemotherapy for patients with some subtypes of breast cancer , added Dr Zee , with hormonal therapy being a good case in point . “ However , there ’ s no less rigorous regimen for patients with pancreatic cancer as the mainstay of treatment remains chemotherapy . �
Two emerging alternatives to chemotherapy are immunotherapy and targeted therapy . And while they represent key advancements in medical oncology that have significantly improved the treatment of several cancers , they haven ’ t played a comparable role in the field of pancreas cancer .
Immunotherapeutic drugs that teach the immune system how to pinpoint and obliterate cancerous tissues can extend the life expectancy of , or even cure , many patients with melanoma ( a common skin malignancy ) and lung cancer but are not yet commonly used against pancreatic cancer as researchers are still trying to demonstrate their usefulness .
�The microenvironment of pancreas cancers is very immunosuppressant ,” said Dr Manji , meaning that malignant cells in the pancreas are able to both fend off detection and attack by the immune system and keep proliferating .
Similarly , the targeted drug imatinib can cure the vast majority of patients with chronic myelogenous leukaemia , a type of blood cancer , by blocking the protein responsible for tumour growth . However , there are no similar targeted therapies that have had a meaningful impact on the treatment of pancreas cancer , acknowledged Dr �ee .
�There are very few targeted treatments that are FDA-approved in the field of pancreatic cancer , � he said . One is Tarceva , which blocks the activity of the cancer-related protein called E�F� and can be prescribed for metastatic malignancies , but it ’ s not commonly used in the clinic because it offers marginal benefits and leads to side effects that can impair quality of life .
Similar to the limits of chemotherapy , the dearth of blood vessels in pancreas tumours affects the efficacy of both immunotherapies and targeted treatments , he believes . �Immunotherapy and targeted therapy require the drugs to reach the cancer to have any form of effect , � Dr �ee said .
What ’ s next for pancreatic cancer treatment ? Research priorities revolve around both the diagnostic and the therapeutic options .
“ An overall goal is to increase resectability ( removal ) by earlier diagnosis and thus improve prognosis and
38 AUGUST 2021 GlobalHealthAsiaPacific . com