In the intricate world of oncology, diagnosing and treating cancer presents myriad challenges, particularly when patients exhibit rare or atypical manifestations of the disease. A compelling example of this complexity recently unfolded with a young patient from the Caribbean who presented with a large, painful scalp mass. Initially diagnosed as locally advanced skin cancer, subsequent investigations led to a surprising and educational twist in his case.
Patient Presentation
The patient, a young man in his early thirties, came to me with a history of significant pain and drainage from a scalp mass that had been troubling him for several weeks. He had previously undergone a biopsy in the Caribbean, which indicated advanced skin cancer. However, the clinical presentation—a large, deep soft tissue mass—prompted us to conduct our own biopsy for a clearer understanding of the pathology.
Surprising Diagnosis
Our pathology team initially identified the mass as malignant melanoma based on morphology and special specific melanoma markers, which was unexpected given the patient’s demographic and the mass’s characteristics. Yet, the true nature of the disease was only revealed through comprehensive genetic testing: a Clear Cell Sarcoma marked by the EWSR1/ATF1 fusion aka t(12,22) —a classic molecular alteration that often masquerades as melanoma. Both malignancies can look exactly the same under the microscope and with special stains. However, the unique molecular revelation highlighted the critical role of genetic insights in modern oncology, especially for cases with unusual presentations.
Treatment and Response
Given the urgency of his symptoms, I had initiated treatment with dual checkpoint immunotherapy with the intent of treating “Melanoma” while awaiting genetic results that carry a 2-3 week turn around time for results. Remarkably and now unexpectedly, the patient responded well to the immunotherapy; his pain significantly decreased, and he reported a perceptible reduction in mass size. This response was particularly notable because Clear Cell Sarcomas typically have low responsiveness to conventional drug therapies, making his initial positive response to immunotherapy a point of keen interest and optimism.
The Challenges of Rare Cancers
Clear Cell Sarcoma, a rare cancer type, often requires a distinct treatment approach. While surgery and radiation are crucial for local-regional control, the effectiveness of chemotherapy and targeted therapies remains limited, underscoring the need for innovative treatment options in these rare malignancies. And the effect of immunotherapies for this rare tumor type is not well known.
The Importance of Genetic Testing
This case underscores the indispensable value of genetic testing in oncology. The identification of the EWSR1/ATF1 fusion was pivotal, not only for accurate diagnosis but also for guiding treatment decisions. It serves as a stark reminder of the necessity for oncologists to maintain a high index of suspicion and consider rare or esoteric diagnoses.
Review article by Smrke et al. at ESMO
Clinical Response and Future Directions
Encouragingly and fortunately, the patient’s initial response to immunotherapy has been positive, with a reduction in pain and perceived shrinkage of the mass. This response, although atypical and again largely unknown for Clear Cell Sarcoma, has provided a hopeful outlook and has led to a re-evaluation of the treatment plan. It underscores the possible benefits of immunotherapy in this rare sarcoma, albeit based on limited evidence.
A patient with CSS responding to radiation and pembrolizumab achieving a complete response.
Takeaway
For oncology professionals, this case serves as a reminder of the complexities involved in diagnosing and treating cancer. Continuous learning and adaptation are key in providing the best care for patients facing these rare and challenging conditions.
Dr. Sajeve Thomas is a distinguished medical professional and a compassionate guide in the field of oncology. With over a decade of dedicated experience as a board-certified medical oncologist/internal medicine specialist, Dr. Thomas has become a trusted expert in the treatment of melanoma, sarcoma, and gastrointestinal conditions. Currently practicing at the renowned Orlando Health Cancer Institute, he brings a wealth of expertise to the complex and challenging world of oncology.