Agressive carcinogenisis: Case studies link extraocular sebaceous carcinoma, immunosuppression

Key Points

Scottsdale, Ariz. - It is common knowledge that immunosuppressed individuals, such as organ transplant recipients (OTRs), are at a significantly higher risk of carcinogenesis, such as the development of basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs).

As two recent case studies show, much more rare and aggressive tumors can also occur in OTRs, such as sebaceous carcinomas, underscoring the importance for this patient population to undergo very stringent screening protocols.

Ocular sebaceous carcinoma

Ocular sebaceous carcinoma is considered more aggressive, with a higher metastatic rate, than extra-ocular disease; however, this notion has recently been challenged.

Case studies

Charles W. Chia, M.D., department of dermatology, Mayo Clinic, Scottsdale, Ariz., recently reported on two OTRs who were both receiving Prograf (tacrolimus, Astellas) immunosuppression therapy and who were subsequently seen to develop sebaceous carcinoma.

Patient 1 was a 59-year-old Caucasian male (liver transplant) who presented with a two-month history of a rapidly enlarging 1.5 cm nodule on the dorsum of the nose. Patient 2 was a 73-year-old Caucasian male (heart transplant) who presented with a rapidly enlarging, blue-black papule on the left nasal sidewall.

Biopsy

The tumors were excised, and histopathology reports were consistent with sebaceous carcinoma in both patients. Sentinel lymph node biopsy in patient 1 was negative, whereas in patient 2, biopsy demonstrated two small clusters of keratin-positive cells of undetermined significance.

Immunohistochemical staining of the tumors of both patients ruled out the possibility of Muir-Torre syndrome.

"Because sebaceous carcinoma is such a rare occurrence, there is a lack of good studies on how to proceed with follow-up treatment in terms of performing a sentinel lymph node biopsy or a lymph node dissection.

"If the tumor seems advanced, then a lymph node dissection is probably warranted. But if it seems local, a sentinel lymph node biopsy may be reasonable, but this has not been established," Dr. Chia tells Dermatology Times.

Unfortunately, diagnostic delay is a common occurrence with sebaceous carcinoma, either due to delayed presentation by the patient or misrecognition and misdiagnosis by the clinician.

Diagnostic delay

Diagnostic delay contributes to a metastatic rate of up to 28 percent and a mortality rate of up to 24 percent. Carcinogenesis is not uncommon in immunosuppressed patients and is especially common in organ transplant recipients.

Role of immunosuppression

Therefore, according to Dr. Chia, it is imaginable that the immunosuppression may have played a role in the development of these two sebaceous carcinoma tumors.

"I believe that immunosuppressed patients should be managed differently in terms of screening. It has been well established over the years that these patients are at a much higher risk of developing BCCs and SCCs and, possibly, even melanomas.

"Furthermore, patients who develop sebaceous carcinoma are at an increased risk of developing visceral malignancies consistent with Muir-Torre syndrome and, therefore, these patients must be screened much more aggressively," Dr. Chia says.

According to Dr. Chia, any time a clinician is confronted with an unknown lesion - especially in the immunosuppressed - that cannot be clearly diagnosed clinically and raises significant suspicion, an immediate biopsy is warranted.