Sebaceous carcinoma (SC) is a rare tumor, accounting for approximately 0.7% of skin cancers. SC can be classified as ocular SC (OSC) or extraocular SC (EOSC) depending on its location. Because EOSC accompanied by metastases is rare, there is a paucity of data about EOSC accompanied by metastasis. This study presents a case of an aggressive EOSC of the scalp with lymph node metastases. The patient underwent wide local excision of the primary tumor with a 1 cm safety margin and bilateral radical lymph node dissection. However, recurrence was observed 1 month after surgery. Radiation therapy and resection were performed for the recurrent tumor. However, distant metastases to both lungs eventually occurred. Here, we describe a rare recurrent case of EOSC of the scalp with distant organ metastasis with a review of the literature.
Sebaceous carcinoma (SC) is a rare tumor that grows in the adnexal epithelial cells of the sebaceous glands. It accounts for 0.7% of all skin cancers [
EOSCs are less common than OSCs, with EOSCs accompanied by metastases being even less common. It has been reported that only 1.4% of EOSCs are associated with regional lymph node metastases or distal organ metastases [
We describe a rare recurrent case of EOSC. The patient was treated with wide local excision and radical lymph node dissection. However, distant metastases developed after 5 months. This study reports the clinical course of this rare case.
A 47-year-old man presenting with a painful mass on the left anterior scalp visited our hospital. The patient had a 40-year history of a yellow patch-like lesion on the same site with an irregular surface accompanied by itching and hair loss. The size of the lesion had not changed over time but had suddenly begun to grow 4 months before.
On physical examination, the patient had a hard, palpable, immobile mass measuring 7×7 cm accompanied by bleeding, discharge, an irregular surface and a red ulcer on the left anterior scalp (
For further evaluation, a punch biopsy and computed tomography (CT) were performed. On CT scans, the patient had an exophytic, heterogeneously enhancing mass measuring 6.9 cm, accompanied by multiple masses on both parotid glands and the posterior neck (
At 3 months, the patient returned to us with bleeding from the scalp mass whose size had increased to 11×11 cm (
Under general anesthesia, wide local excision was performed, including excision of entire layers of the scalp with a 1-cm safety margin. In frozen sections, no tumor cells were observed at the resection margins, including the deep margin.
After resection, the size of the defect was measured as 13×13 cm. We planned for a V-Y island flap for which the parietal branch of the left superficial temporal artery served as a pedicle. A triangular flap was designed on the posterior area of the defect. We performed a subcutaneous fat layer dissection from the side of the pedicle up to 3 cm above the ear. To elevate the flap, we performed a subgaleal dissection from the opposite side of the pedicle to 3 cm above the ear. The defect was reconstructed by advancement of the flap. The donor site defect was located on the posterolateral side of the vertex. To reduce the skin graft area and move it to the posterolateral side, an inferiorly based rotation flap using the occipital scalp was performed. The area remaining after the rotation flap was covered by split thickness skin graft. This was followed by bilateral radical neck lymph node dissection and lymph node biopsy.
The surgical biopsy revealed a large solid tumor characterized by ulcerative cutaneous lesions that occupied vast portions of the dermis with infiltrative growth. Moreover, there were well-defined, solid lobules of neoplastic cells composed of large, pale or clear cells with coarsely vacuolated cytoplasm and focal squamoid differentiation. Such neoplastic cells were well to moderately differentiated and had a lobular infiltrative pattern (
At a 1-month follow-up, the patient had three recurrent tumors, measuring 1×1 cm, on the surgical margin of the scalp (
At 5 months, the patient complained of dyspnea even while walking on flat ground. Chest radiography revealed the presence of multiple nodules in both lungs, which were not previously present (
In this case, the patient had a history of a patch-like scalp lesion that had not increased in size for 40 years. However, it suddenly began to grow and protrude 4 months before. Such a history suggested the possibility of malignant transformation of a benign lesion. Although rare, previous studies have reported cases of nevus sebaceous changes into SC [
SC can be classified as OSC and EOSC. It is known that 75% of SCs are OSCs and 25% of SCs are EOSCs [
Since only 1.4% of EOSCs are accompanied by metastases [
It has been reported that the 8th American Joint Committee on Cancer (AJCC) TNM staging of cutaneous squamous cell carcinoma and other cutaneous carcinomas can be used for staging EOSCs. A study has shown that local recurrence and disease-specific survival outcomes can be predicted based on the T and N results of OSC [
Owing to its rarity, the standard treatment of SC has not yet been established. It is known that the treatment of SC is excision of the primary tumor with wide local excision or Mohs micrographic surgery (MMS) [
In this case, distant metastases were not initially observed. The tumor was larger than 2 cm in size with bilateral lymph node metastases, and the TNM stage was T2N2cM0. Since the tumor was on the scalp without involving the vital structure, it seemed possible to resect the primary tumor [
The recurrence rate of EOSC is known to be 29%, with an average period to recurrence of 19.4 months [
Radiation therapy is used as an adjuvant therapy in the treatment of EOSC. However, as radiation therapy is rarely performed to treat EOSC, the effectiveness of radiation therapy has not yet been proven. In a review of 1,349 cases, it was reported that only 5.3% of SC patients had been treated by surgery with adjuvant radiation therapy [
In conclusion, we experienced a rare recurrent case of aggressive EOSC of the scalp with distant organ metastasis. We performed the pre-existing treatment for this case. However, to treat such aggressive tumors, it seems that other treatment options are needed. Since only a limited number of cases of aggressive EOSC have been reported, treatment modalities for aggressive EOSC have not been established. Therefore, further studies are warranted to determine the treatment options in this series.
No potential conflict of interest relevant to this article was reported.
The study was approved by the Institutional Review Board of Inje University Busan Paik Hospital (IRB No. 20-0175) and performed in accordance with the principles of the Declaration of Helsinki. Written informed consent was obtained.
The patient provided written informed consent for the publication and the use of his images.
Conceptualization: JWK. Project administration: JWK. Resources: JWK. Writing - original draft: BSK. Writing - review & editing: BSK, EHC. Approval of final manuscript: all authors.
Initial photograph. A 47-year-old man presented with a mass 7×7 cm in size on the left anterior scalp.
Computed tomography (CT) scans of the lymph nodes. A CT image (yellow asterisks) shows several enhanced masses in the cervical lymph nodes and both parotid lymph nodes.
Clinical photograph at 3 months after the first visit. The size of the mass has increased to 11×11 cm.
Histopathologic findings. (A) An ulcerative cutaneous lesion is observed. Neoplastic cells are characterized by a lobular growth pattern (marked with a square) (H&E, ×100). (B) Neoplastic cells contain well-defined solid lobules that are composed of large, pale or clear cells with coarsely vacuolated cytoplasm (marked with a circle) and focal squamoid differentiation (black asterisk) (H&E, ×250).
Clinical photograph at 1 month after surgery. At 1 month postoperatively, recurrent lesions were observed (black asterisks).
Posterior-anterior chest radiography at 4 months after surgery for recurrent tumors. Multiple nodules (yellow arrows) are present in both lungs.