Is imatinib the underutilised dermatofibrosarcoma protuberans miracle?

Thandeka Malange expands on dermatofibrosarcoma protuberans and the imatinib treatment option through the story of a patient, Mr Tlakedi.

Dermatofibrosarcoma protuberans (DFSP)

DFSP is a slow-growing tumour which can grow anywhere on the body. It’s a rare type of skin cancer that involves the deeper layers of the skin and can grow into the surrounding tissues, such as fat, muscle and bone.¹  

Typically, DFSP presents in 20-59-year-old persons. However, it can occur at any age and males are generally more affected than females.¹ 

It seldom spreads to other parts of the body and tends to recur at the site of excision.¹

Mr Tlakedi

Mr Tlakedi is a husband, father of two, and an organic farmer in Ceres. He was diagnosed with DFSP of the arm in 2020. 

Since the skin is the largest organ, it’s of no surprise that we notice every spot and bump on it. However, it could be a sign of DFSP, when: 

• Flat or raised part of skin is firm or rubbery to touch.
• It is painful and itchy.  
• There are changes in the lesion. 
• The lesion bleeds.
• Doesn’t stop growing or recurs.

For example, Mr Tlakedi thought he had a spider bite, in 2015, but upon multiple recurrence, a biopsy was taken and the results confirmed the diagnosis. Mercifully, Mr Tlakedi, who describes himself as an optimist and faithful man, had no fear and believed he would be cured. 

Imatinib treatment

Despite waiting a lengthy time to get treated because of COVID-19 lockdown regulations, he kept this positive outlook. He was finally referred to the oncology division at Tygerberg Hospital where he was given different treatment options. One of these was the newer generation pill, called imatinib; the doctors explained that his tumour was too large to be resected surgically and that the pill would help shrink it. 

Imatinib is a cancer growth blocker, called a tyrosine kinase inhibitor. It’s used to shrink large or metastatic tumours as it inhibits tyrosine kinase which blocks cancer growth.²

The treatment takes roughly three to six months and is generally well-tolerated. In Mr Tlakedi’s case, the only side effect he reported was dizziness. However, he was counselled on other side effects, such as loss of appetite, headache, blurred vision, skin rashes and nausea.

It’s important to note that side effects differ from person-to-person and some are managed with dose-adjustment or other specific measures.

Immediate results

Mr Tlakedi highly recommends this treatment for people with DFSP as he saw results immediately. Furthermore, he explains that his tumour used to bleed and this would affect his choice of clothing but since taking the tablet, it bleeds less. 

The oral tablet was taken daily, as it was emphasised that compliance was of extreme importance and he heeded this advice. Upon taking the very first dose, Mr Tlakedi noticed that the tumour was getting ‘sucked’ in. He was impressed. The farmer continued with the pill for two months since October and his tumour shrunk tremendously, which meant he could have his tumour surgically removed. The surgery occurred a week later.

This therapeutic choice, imatinib, is on the rise and has demonstrated great potential in the treatment of DSFP, especially those that aren’t surgically resectable.³ 

As surgery is deemed the gold standard of the treatment of DFSP, imatinib is a form of underutilised therapy as patients are unaware of it. It’s minimally invasive and special motivation is given for certain patients in the public sector to receive the treatment for free, as is the case with Mr Tlakedi. 

With constant follow-ups to observe progress and screen for side effects, many can also have the wonderful, victorious ending described above.

References

1. 6. Dermatofibrosarcoma protuberans | DermNet NZ [Internet]. Dermnetnz.org. 2020 [cited 11 December 2020]. Available from: https://dermnetnz.org/topics/dermatofibrosarcoma-protuberans/
2. Iqbal N, Iqbal N. Imatinib: A Breakthrough of Targeted Therapy in Cancer. Chemotherapy Research and Practice. 2014;2014:1-9. 
3. Navarrete-Dechent C, Mori S, Barker C, Dickson M, Nehal K. Imatinib Treatment for Locally Advanced or Metastatic Dermatofibrosarcoma Protuberans. JAMA Dermatology [Internet]. 2019;155(3):361. Available from: https://jamanetwork.com/article.aspx?doi=10.1001/jamadermatol.2018.4940