Isolated Kaposi Sarcoma of the External Ear: A Rare Presentation in an Immunocompromised Host

Introduction: Kaposi sarcoma (KS) is a vascular neoplasm associated with HHV-8 infection, often arising in immunocompromised patients, especially those with HIV (Dittmer 2016). Isolated involvement of the external ear is rare and can clinically resemble infection, cysts, or keloids.

Case Presentation: A 31-year-old man presented with a month-long history of a rapidly enlarging, painful right auricular mass associated with periorbital swelling. Initial evaluation in a prior emergency visit suggested a sebaceous cyst. On current presentation, the mass showed purulent drainage, and the patient had severe pancytopenia, iron-restricted anemia, and HIV reactivity. ENT evaluation described an exophytic superior-pinna mass with suspected superinfection and initiated ciprofloxacin and local wound care, with plans for excision once inflammation improved. CT imaging demonstrated a heterogeneous 2.2 × 1.9 cm exophytic soft-tissue mass arising from the pinna. Surgical excision revealed classic KS morphology. Pathology showed a unifocal, 2.5 cm lesion with histologic and immunohistochemical features of Kaposi sarcoma: HHV-8+, CD31+, CD34+  spindle-cell proliferation. Mitotic rate was 21/10 HPF. Margins were viable; no lymphovascular invasion identified.

Discussion: Auricular KS is rare and often presents without systemic symptoms, complicating early diagnosis. Purulence and tenderness may mimic infection, and keloid-like morphology may confound evaluation. This case demonstrates how overlapping clinical features necessitate biopsy to distinguish KS from benign or infectious ear lesions.

Conclusion: External ear KS should be included in the differential diagnosis of persistent or atypical auricular masses, especially in immunocompromised patients. Early tissue diagnosis and multidisciplinary coordination optimize outcomes.

Main Text:

Main text:

Introduction:

Kaposi sarcoma (KS) is a low-grade vascular neoplasm driven by HHV-8 infection and promoted by immune dysregulation. It most commonly involves cutaneous sites on the extremities, oral mucosa, or trunk, particularly in individuals with untreated HIV infection [1]. Auricular involvement is exceedingly rare, and KS of the external ear may mimic benign conditions such as epidermoid cysts, keloids, pyogenic granulomas, or inflammatory lesions [2]. The diagnostic challenge is increased by overlapping clinical features including discoloration, swelling, pain, and even purulent drainage that can suggest infection rather than neoplasia. We present a case of isolated auricular KS in a patient with newly identified HIV-associated immunosuppression whose presentation initially resembled a superinfected keloid or cyst and required multidisciplinary evaluation before diagnosis.

Case Presentation:

A 31-year-old man presented to the emergency department complaining of a progressively enlarging auricular mass with right ear pain and periorbital swelling. He had a past medical history of asthma and proctitis. His family history was noncontributory and he consumed 2 glasses of wine a month. His pain was severe and radiated toward the periorbital region, requiring 2000 mg ibuprofen three times daily (TID) and 1500 mg acetaminophen TID for one week. He denied fever, visual changes, nasal drainage, or systemic symptoms. He reported a similar episode one month earlier, where the auricular lesion was thought to be a sebaceous cyst with possible dacryocystitis. He was then treated with Augmentin (amoxicillin/clavulanate) and advised to avoid incision and drainage.

Clinical Findings

On presentation, the patient had stable vital signs. He appeared well and in no acute distress, with intact extraocular movements and clear conjunctiva. Examination of the right external ear revealed a large exophytic mass arising from the superior pinna with purulent drainage and marked tenderness, without erythema of the external canal. The neck exhibited normal range of motion without lymphadenopathy. Review of systems was negative for fever, visual disturbances, nasal symptoms, or sore throat.

Laboratory Evaluation

Initial and repeat laboratory studies showed progressively worsening pancytopenia, with the leukocyte count declining from 1.5 to 1.2 × 10⁹/L (5.0-10.0 x10⁹/L), hemoglobin falling from 7.7 to 6.9 g/dL (14-18 g/dL), platelets decreasing from 131 to 118 × 10⁹/L (150-400 x10⁹/L), and the red cell distribution width increasing to 15.5 (11.0-14.5%). Iron studies demonstrated anemia of chronic disease, with serum iron of 27 mcg/dL (50-150 ug/dL), iron saturation of 10% (20-50%), and ferritin of 869.88 ng/mL (12-300 pg/mL) [3]. HIV testing returned reactive.

Treatment

A head CT was obtained as seen in Figure 1, showing a 2.2 × 1.9 cm heterogeneous exophytic soft-tissue mass extending from the right pinna with no bony destruction or deep extension. A MRI was recommended for further characterization but was unable to be obtained due to the patient's insurance. The patient was subsequently admitted to the hospital and prescribed empiric Zosyn (piperacillin-tazobactam) 100 mL IV, morphine 0.5 mL IV every 3 hours as needed, Neupogen (filgrastim) one shot, and Biktarvy (bictegravir, emtricitabine & tenofovir alafenamide) 50 mg-200 mg-25 mg oral tablet. IV Zosyn was later changed to Cubicin (daptomycin) 10 mL IV. Otolaryngology was consulted, recommending warm compresses and wet-to-dry dressings with excision planned after inflammation reduced.

Surgical Excision and Pathology

One day before discharge, the lesion was excised. Grossly, the excised lesion was a gray-tan nodular soft tissue mass measuring 2.5 × 2.2 × 2.0 cm, and serial sectioning revealed a dark-red cystic hemorrhagic cut surface. Histologic evaluation demonstrated a malignant vascular spindle-cell neoplasm composed of intersecting fascicles forming slit-like anastomosing vascular spaces with prominent extravasated red blood cells, hemosiderin deposition, and a patchy inflammatory infiltrate, represented by Figure 2. The tumor showed mild to moderate cytologic atypia and markedly increased mitotic activity, measured at 21 mitoses per 10 HPF. Immunohistochemistry showed diffuse positivity for HHV-8, CD31+, and CD34+, with negative staining for S-100 and desmin, confirming the diagnosis of Kaposi sarcoma.

Outcome and Follow-up

The patient’s discharge medications included Augmentin one tablet every twelve hours, doxycycline 100 mg twice daily, and hydrocodone-acetaminophen one tablet every six hours as needed for pain for one week. Additional medications included penicillin G benzathine 2.4 million units intramuscularly weekly for two weeks (4 mL per dose, total 8 mL) and Biktarvy one tablet daily indefinitely.

He was scheduled for follow-up within one week with ophthalmology, otolaryngology, and the Positive Impact Health Center for HIV care. Additional follow-up with his primary care provider was arranged for one to two weeks after discharge. At the time of the last follow-up with otolaryngology, his auricular surgical site remained well-healed with no evidence of recurrence.

Discussion:

Pathophysiology

Kaposi sarcoma arises from HHV-8 driven vascular proliferation in the setting of immunosuppressive conditions such as HIV [1]. Auricular involvement is rare, and lesions of the external ear may develop gradually without the classic violaceous discoloration associated with more typical mucocutaneous sites [2].

Differential Diagnosis

The differential diagnosis for a painful or draining auricular mass includes an inflamed epidermal inclusion cyst, a keloid with secondary infection, pyogenic granuloma, angiosarcoma, bacillary angiomatosis, and Kaposi sarcoma. Dermatofibrosarcoma protuberans may also be considered given its CD34+ positivity, though it lacks HHV-8 expression. Angiosarcoma is typically more pleomorphic and is also HHV-8 negative. Spindle cell melanoma is excluded by the absence of S-100 staining. HHV-8 positivity strongly supports Kaposi sarcoma and CD31+ and CD34+ positivity confirm vascular lineage [4]. Because of similar presentation, biopsy remains essential for any persistent, atypical, or recurrent auricular lesion, particularly in individuals with known or suspected immune dysfunction.

Management Considerations

Management of localized Kaposi sarcoma centers on complete surgical excision and optimization of immune status. For patients with HIV, initiation of antiretroviral therapy is essential. Routine clinical surveillance is advised to monitor for local recurrence. Systemic therapy is reserved for multifocal, visceral, or refractory disease [5]. In this patient, postoperative healing was uncomplicated, facial swelling improved, and he initiated antiretroviral therapy with multidisciplinary follow-up.

Conclusion:

This case illustrates a rare presentation of Kaposi sarcoma of the auricle confirmed by characteristic histopathology and HHV-8 immunoreactivity. In patients with HIV-associated immunosuppression, early biopsy with coordinated otolaryngology and infectious disease management are essential to prevent diagnostic delay and ensure optimal outcomes.

Figure 1: Histopathologic features of Kaposi sarcoma demonstrating spindle-cell vascular proliferation with the promontory sign, characteristic of Kaposi sarcoma.

Isolated Kaposi Sarcoma of the External Ear: A Rare Presentation in an Immunocompromised Host

Authors:

David Joseph Dillard^a, Colten Witte, Shu K. Lui, Magalie Nelson Charles

Affiliations:

^aSleep and Sinus Centers of Georgia 1990 Riverside Pkwy, Lawrenceville GA, USA 30046

Department of Pathology: Northside Hospital 1000 Johnson Ferry Road NE, Atlanta GA, USA 30342

Department of Otolaryngology: Northside Hospital 1000 Medical Center Blvd, Lawrenceville GA, USA 30046

Corresponding Author:

David Joseph Dillard 

Email: dillard.david.joseph@gmail.com

Abstract: 

Introduction: Kaposi sarcoma (KS) is a vascular neoplasm associated with HHV-8 infection, often arising in immunocompromised patients, especially those with HIV (Dittmer 2016). Isolated involvement of the external ear is rare and can clinically resemble infection, cysts, or keloids.

Case Presentation: A 31-year-old man presented with a month-long history of a rapidly enlarging, painful right auricular mass associated with periorbital swelling. Initial evaluation in a prior emergency visit suggested a sebaceous cyst. On current presentation, the mass showed purulent drainage, and the patient had severe pancytopenia, iron-restricted anemia, and HIV reactivity. Otolaryngology evaluation described an exophytic superior-pinna mass with suspected superinfection and initiated ciprofloxacin and local wound care, with plans for excision once inflammation improved. CT imaging demonstrated a heterogeneous 2.2 × 1.9 cm exophytic soft-tissue mass arising from the pinna. Surgical excision revealed classic KS morphology. Pathology showed a unifocal, 2.5 cm lesion with histologic and immunohistochemical features of Kaposi sarcoma: HHV-8+, CD31+, CD34+  spindle-cell proliferation. Mitotic rate was 21/10 HPF. Margins were viable; no lymphovascular invasion identified.

Discussion: Auricular KS is rare and often presents without systemic symptoms, complicating early diagnosis. Purulence and tenderness may mimic infection, and keloid-like morphology may confound evaluation. This case demonstrates how overlapping clinical features necessitate biopsy to distinguish KS from benign or infectious ear lesions.

Conclusion: External ear KS should be included in the differential diagnosis of persistent or atypical auricular masses, especially in immunocompromised patients. Early tissue diagnosis and multidisciplinary coordination optimize outcomes.

250 words at 242

Keywords:Kaposi sarcoma; HHV-8; auricular neoplasm; vascular tumor; HIV-associated malignancy

Introduction: 

Kaposi sarcoma (KS) is a low-grade vascular neoplasm driven by HHV-8 infection and promoted by immune dysregulation. It most commonly involves cutaneous sites on the extremities, oral mucosa, or trunk, particularly in individuals with untreated HIV infection [1]. Auricular involvement is exceedingly rare, and KS of the external ear may mimic benign conditions such as epidermoid cysts, keloids, pyogenic granulomas, or inflammatory lesions [2]. The diagnostic challenge is increased by overlapping clinical features including discoloration, swelling, pain, and purulent drainage that can suggest infection rather than neoplasia. We present a case of isolated auricular KS in a patient with newly identified HIV-associated immunosuppression whose presentation initially resembled a superinfected keloid or cyst and required multidisciplinary evaluation before diagnosis.

Case Presentation: 

A 31-year-old man presented to the emergency department complaining of an auricular mass that rapidly grew after trauma with right ear pain and periorbital swelling. He had a past medical history of asthma and proctitis. His family history was noncontributory and he consumed 2 glasses of wine a month. His pain was severe and radiated toward the periorbital region, requiring 2000 mg ibuprofen three times daily (TID) and 1500 mg acetaminophen TID for one week. He denied fever, visual changes, nasal drainage, or systemic symptoms. He reported a similar episode one month earlier, where he was thought to have a sebaceous cyst on the ear with concomitant dacryocystitis. He was then treated with Augmentin (amoxicillin/clavulanate) for the dacrocystitis and advised to avoid incision and drainage.

On presentation, the patient had stable vital signs. He appeared well and in no acute distress, with intact extraocular movements and clear conjunctiva. His right periorbital area was swollen. Examination of the right external ear revealed a large exophytic mass arising from the superior pinna with purulent drainage and marked tenderness, without erythema of the external canal. The neck exhibited normal range of motion without lymphadenopathy. Review of systems was negative for fever, visual disturbances, nasal symptoms, or sore throat. 

Initial and repeat laboratory studies showed progressively worsening pancytopenia, with the leukocyte count declining from 1.5 to 1.2 × 10⁹/L (5.0-10.0 x10⁹/L), hemoglobin falling from 7.7 to 6.9 g/dL (14-18 g/dL), platelets decreasing from 131 to 118 × 10⁹/L (150-400 x10⁹/L), and the red cell distribution width increasing to 15.5 (11.0-14.5%). Iron studies demonstrated anemia of chronic disease, with serum iron of 27 mcg/dL (50-150 ug/dL), iron saturation of 10% (20-50%), and ferritin of 869.88 ng/mL (12-300 pg/mL) [3]. HIV testing returned reactive. RPR testing was positive for syphilis. 

A head CT was obtained as seen in Figure 1, showing a 2.2 × 1.9 cm heterogeneous exophytic soft-tissue mass extending from the right pinna with no bony destruction or deep extension. A MRI was recommended for further characterization but was unable to be obtained due to the patient's insurance. The patient was subsequently admitted to the hospital and prescribed empiric Zosyn (piperacillin-tazobactam) 100 mL IV, morphine 0.5 mL IV every 3 hours as needed, Neupogen (filgrastim) one shot, and Biktarvy (bictegravir, emtricitabine & tenofovir alafenamide) 50 mg-200 mg-25 mg oral tablet for HIV. IV Zosyn was later changed to Cubicin (daptomycin) 10 mL IV. Otolaryngology was consulted, recommending warm compresses and wet-to-dry dressings with excision planned after inflammation reduced. 

One day before discharge, the lesion was excised. Grossly, the excised lesion was a gray-tan nodular soft tissue mass measuring 2.5 × 2.2 × 2.0 cm, and serial sectioning revealed a dark-red cystic hemorrhagic cut surface. Histologic evaluation demonstrated a malignant vascular spindle-cell neoplasm composed of intersecting fascicles forming slit-like anastomosing vascular spaces with prominent extravasated red blood cells, hemosiderin deposition, and a patchy inflammatory infiltrate, represented by Figure 2. The tumor showed mild to moderate cytologic atypia and markedly increased mitotic activity, measured at 21 mitoses per 10 HPF. Immunohistochemistry showed diffuse positivity for HHV-8, CD31+, and CD34+, with negative staining for S-100 and desmin, confirming the diagnosis of Kaposi sarcoma.

The patient’s discharge medications included Augmentin one tablet every twelve hours, doxycycline 100 mg twice daily, and hydrocodone-acetaminophen one tablet every six hours as needed for pain for one week. Additional medications included penicillin G benzathine 2.4 million units intramuscularly weekly for two weeks (4 mL per dose, total 8 mL) for syphilis and Biktarvy one tablet daily indefinitely. 

He was scheduled for follow-up within one week with primary care, otolaryngology, ophthalmology for surgery for dacryocystitis, and the Positive Impact Health Center for HIV care. At the time of the last follow-up with otolaryngology, his surgical site remained well-healed with no evidence of recurrence.

Discussion: 

Kaposi sarcoma arises from HHV-8 driven vascular proliferation in the setting of immunosuppressive conditions such as HIV [1]. Auricular involvement is rare, and lesions of the external ear may develop gradually without the classic violaceous discoloration associated with more typical mucocutaneous sites [2].

The differential diagnosis for a painful or draining auricular mass includes an inflamed epidermal inclusion cyst, a keloid with secondary infection, pyogenic granuloma, angiosarcoma, bacillary angiomatosis, and Kaposi sarcoma. Dermatofibrosarcoma protuberans may also be considered given its CD34+ positivity, though it lacks HHV-8 expression. Angiosarcoma is typically more pleomorphic and is also HHV-8 negative. Spindle cell melanoma is excluded by the absence of S-100 staining. HHV-8 positivity strongly supports Kaposi sarcoma and CD31+ and CD34+ positivity confirm vascular lineage [4]. Because of similar presentation, biopsy remains essential for any persistent, atypical, or recurrent auricular lesion, particularly in individuals with known or suspected immune dysfunction.

Management of localized Kaposi sarcoma centers on complete surgical excision and optimization of immune status. For patients with HIV, initiation of antiretroviral therapy is essential. Routine clinical surveillance is advised to monitor for local recurrence. Systemic therapy is reserved for multifocal, visceral, or refractory disease [5]. In this patient, postoperative healing was uncomplicated, facial swelling improved, and he initiated antiretroviral therapy with multidisciplinary follow-up.

Conclusion: 

This case illustrates a rare presentation of Kaposi sarcoma of the auricle confirmed by characteristic histopathology and HHV-8 immunoreactivity. In patients with HIV-associated immunosuppression, early biopsy with coordinated otolaryngology and infectious disease management are essential to prevent diagnostic delay and ensure optimal outcomes.

1000 words, 1002

References:

1. Cesarman E, Damania B, Krown SE, Martin J, Bower M, Whitby D. Kaposi sarcoma. Nat Rev Dis Primers. 2019;5(1):9. Published 2019 Jan 31. doi:10.1038/s41572-019-0060-9

2. Agaimy A, Mueller SK, Harrer T, Bauer S, Thompson LDR. Head and Neck Kaposi Sarcoma: Clinicopathological Analysis of 11 Cases. Head Neck Pathol. 2018;12(4):511-516. doi:10.1007/s12105-018-0902-x

3. Abimbola Farinde P. Lab Values, Normal Adult. Laboratory Reference Ranges in Healthy Adults. July 28, 2025. Accessed December 3, 2025. https://emedicine.medscape.com/article/2172316-overview. 

4. Phung TL. Histopathology of Vascular Tumors. Dermatol Clin. 2022;40(4):357-366. doi:10.1016/j.det.2022.06.009

5. Russo I, Marino D, Cozzolino C, et al. Kaposi's Sarcoma: Evaluation of Clinical Features, Treatment Outcomes, and Prognosis in a Single-Center Retrospective Case Series. Cancers (Basel). 2024;16(4):691. Published 2024 Feb 6. doi:10.3390/cancers16040691

Figure 1: CT findings of right auricular Kaposi sarcoma showing an enhancing soft-tissue mass without bony invasion.

Figure 2: Histopathologic features of Kaposi sarcoma demonstrating spindle-cell vascular proliferation with the promontory sign, characteristic of Kaposi sarcoma.

A: Immunohistochemistry showing strong nuclear staining. B: Plaque-stage KS with spindle cell proliferation, slit-like vascular spaces, and extravasated RBCs. C: KS with more stromal change and hemorrhage; spindle cells and slit-like vascular spaces still present but less dense.

A: Immunohistochemistry showing strong nuclear staining (not used for KS triad). B: Plaque-stage KS with spindle cell proliferation, slit-like vascular spaces, and extravasated RBCs. C: KS with more stromal change and hemorrhage; spindle cells and slit-like vascular spaces still present but less dense.

Figure 2: CT findings of right auricular Kaposi sarcoma showing an enhancing soft-tissue mass without bony invasion.

References:

1. Cesarman E, Damania B, Krown SE, Martin J, Bower M, Whitby D. Kaposi sarcoma. Nat Rev Dis Primers. 2019;5(1):9. Published 2019 Jan 31. doi:10.1038/s41572-019-0060-9

2. Agaimy A, Mueller SK, Harrer T, Bauer S, Thompson LDR. Head and Neck Kaposi Sarcoma: Clinicopathological Analysis of 11 Cases. Head Neck Pathol. 2018;12(4):511-516. doi:10.1007/s12105-018-0902-x

3. Abimbola Farinde P. Lab Values, Normal Adult. Laboratory Reference Ranges in Healthy Adults. July 28, 2025. Accessed December 3, 2025. https://emedicine.medscape.com/article/2172316-overview.

4. Phung TL. Histopathology of Vascular Tumors. Dermatol Clin. 2022;40(4):357-366. doi:10.1016/j.det.2022.06.009

5. Russo I, Marino D, Cozzolino C, et al. Kaposi's Sarcoma: Evaluation of Clinical Features, Treatment Outcomes, and Prognosis in a Single-Center Retrospective Case Series. Cancers (Basel). 2024;16(4):691. Published 2024 Feb 6. doi:10.3390/cancers16040691