LETTERS AND COMMUNICATIONS
hidroacanthoma simplex, also known as porocarcinoma in situ, is a rare slow-growing tumor that rarely metastasizes. Clinically, it appears similar to a seborrheic keratosis or Bowen disease and is often misdiagnosed until biopsy. However, hidroacanthoma simplex with dermal invasion is regarded as porocarcinoma, which has a less favorable prognosis and higher chance of metastasis.1 Malignant transformation of hidroacanthoma simplex can occur, and dermatologists also must monitor for progression to invasive porocarcinoma.1 A study by Anzai et al2 reported malignant transformation in 10% of their 70 cases. Early excision or MMS has been suggested even for the benign form of hidroacanthoma simplex because of the risk for malignant transformation.1 To the best of the authors’ knowledge, there are no reports of using MMS to treat malignant hidroacanthoma simplex, as the literature thus far only discusses conventional surgical excision for this neoplasm, without defined surgical margins. In the 3 articles that reported recurrence rates after performing conventional surgical excision, there was no recurrence at average 34 months.1,3,4 Mohs micrographic surgery has shown to be a very effective therapy for a number of contiguous malignant cutaneous tumors and has been successfully used in few cases of porocarcinoma as well.5 In treating porocarcinomas, MMS compared favorably with wide local excision with no local recurrences for as long as 60-month follow-up. In this case, given that the patient was immunocompromised (chronic lymphocytic leukemia) and the in situ tumor was located on the scalp, MMS was recommended when following the guidelines of the Mohs Appropriate Use Criteria for an equivalent tumor such as squamous cell carcinoma in situ. The surgery emphasized the need
for MMS, given that it involved 4 stages with approximately 3-cm margins to clear the tumor, despite a small preclinical appearance. In conclusion, this case adds to the literature of this rare malignant neoplasm and showcases MMS as another effective treatment option for this tumor, especially in areas where tissue sparing is paramount.
References 1. Lee JB, Oh CK, Jang HS, Kim MB, et al. A case of porocarcinoma from pre-existing hidroacanthoma simplex: need of early excision for hidroacanthoma simplex? Dermatol Surg 2003;29:772–4. 2. Anzai S, Arakawa S, Fujiwara S, Yokoyama S. Hidroacanthoma simplex: a case report and analysis of 70 Japanese cases. Dermatology 2005;210:363–5. 3. Piqué E, Olivares M, Espinel ML, Fariña M, et al. Malignant hidroacanthoma simplex. A case report and literature review. Dermatology 1995;190:72–6. 4. Lu X, Wu M, Chen J, Wu J, et al. A case of hidroacanthoma simplex. Indian J Dermatol 2013;58:245. 5. Wildemore JK, Lee JB, Humphreys TR. Mohs surgery for malignant eccrine neoplasms. Dermatol Surg 2004;30:1574–9.
Nita Kohli, MD, MPH Department of Dermatology University Hospitals Case Medical Center Case Western Reserve University Cleveland, Ohio Silvia Soohyun Kim, MD Shang I. Brian Jiang, MD Department of Dermatology University of California, San Diego San Diego, California The authors have indicated no significant interest with commercial supporters.
Commentary on Malignant Hidroacanthoma Simplex Treated With Mohs Surgery The author reads the article entitled “Malignant hidroacanthoma simplex treated with Mohs surgery” by Kohli and colleagues1 with great interest. This is an important “rare” nonmelanoma skin cancer that many Mohs surgeons will see in the span of their career, and
520
Mohs surgeons should be aware of the clinical presentation, nosology, histology, and treatment options. The classification, subclassification, and terminology of these eccrine neoplasms have been the subject of much
DERMATOLOGIC SURGERY
© 2015 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
LETTERS AND COMMUNICATIONS
debate in the dermatopathology literature over the last many decades. At present, it is generally accepted among dermatopathologists that there exists a group of eccrine neoplasms collectively referred to as poromas. These are further subdivided into eccrine poroma (epidermal and dermal components of poroma), dermal duct tumor (dermal eccrine poroma), and hidroacanthoma simplex (intraepidermal eccrine poroma). Less commonly encountered eccrine neoplasms also include syringoacanthoma and syringofibroadenoma. The malignant counterparts are broadly termed eccrine carcinomas but specifically are termed porocarcinoma and malignant hidroacanthoma simplex (or porocarcinoma in situ). These entities are the eccrine neoplasms that most dermatologic surgeons are likely to be asked to treat, particularly with Mohs micrographic surgery. In the larger series of eccrine carcinomas published,2,3 very few cases have been in situ variants (malignant hidroacanthoma simplex), and as such, the natural history of these carcinomas is not well defined. The author, however, assumes that these lesions will behave like squamous cell carcinoma in situ and given time they may acquire invasive and malignant potential. In the case presented by Kohli and colleagues, the clinical margins were quite indistinct and required 4 stages of micrographic surgery to be cleared. The clinically
indistinct margins in this case further suggest that Mohs micrographic surgery was appropriate as it would have been in a similar case of squamous cell carcinoma in situ. In regards to benign eccrine neoplasms, there is literature demonstrating malignant transformation of hidroacanthoma simplex4–6 and other poromas,7 and thus, a strong argument can be made for complete sampling of seemingly benign eccrine neoplasms. Anzai and colleagues5 report in their series of 70 cases of hidroacanthoma simplex in the Japanese population that 10% progressed to eccrine carcinoma. Given these data, it is reasonable to perform complete excisions of these lesions to assure appropriate sampling and prevent recurrence. Both the benign and malignant variants of eccrine neoplasms are clinically heterogeneous.3 Many eccrine neoplasms are clinically mistaken for seborrheic keratosis, squamous cell carcinoma in situ (Bowen disease), basal cell carcinoma, or pyogenic granuloma. The author has personally treated a case that was clinically thought to be seborrheic keratosis, but the pathology represented malignant hidroacanthoma simplex (porocarcinoma in situ). The case treated by the author arose in a 73-year-old Indian female who had a lesion present on her
Figure 1. (A) 5.0- · 3.0-cm plaque resembling large seborrheic keratosis. The defect (B) after diagnosis of porocarcinoma in situ and 2 stages of Mohs micrographic surgery. (C) Low-power (·40) of the histology demonstrating expansion of the epidermis with crowding of cells and numerous ductal structures. (D) Higher power (·400) with numerous apoptotic and mitotic cells with demonstration of many small luminal ducts.
41:4:APRIL 2015
521
© 2015 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
LETTERS AND COMMUNICATIONS
abdomen for 9 years with recent slow growth (Figure 1). She presented with a 5.0- · 3.0-cm verrucous plaque with complaints of itching and bleeding. Biopsy revealed an atypical poroid neoplasm with mitotic and apoptotic activity and ductal differentiation consistent with porocarcinoma in situ (Figure 1). The tumor was cleared with 2 stages of Mohs surgery. The debulk specimen was sectioned and did not contain any evidence of invasive disease. The lymph node examination was normal, and the patient has had no recurrence of the tumor after 12 months of follow-up. This case is similar to that presented by Kohli and colleagues and further reinforces both the index of suspicion needed for biopsy of these lesions and the effectiveness of Mohs surgery for treating these lesions. Ultimately, as dermatologic surgeons, we are attempting to treat carcinomas at early stages to prevent invasive disease and extensive locoregional spread. Not much literature exists regarding treatment of porocarcinomas with Mohs surgery,8,9 and in these small series, Mohs surgery seems to have been successful in treating local disease. Invasive porocarcinoma in the largest series of 54 patients with follow-up2 had 9 (17%) develop local recurrence, 10 (19%) develop nodal disease, and 6 (11%) develop distant metastases or death. A case of metastatic disease after Mohs surgery has been reported,10 with metastatic disease occurring 2 years after initial clear margins by Mohs surgery. This case serves as a reminder of the potential for these tumors to cause significant morbidity and mortality. As the author says to his residents, “Always respect the squamous cell carcinoma.” The same can be said for rare forms of skin cancer such as
porocarcinoma, which given time, can also be destructive and potentially deadly.
References 1. Kohli N, Soohyun Kim S, Brian Jiang SI. Malignant hidroacanthoma simplex treated with Mohs surgery. Dermatol Surg 2015;41:518–520. 2. Mehregan AH, Hashimoto K, Rahbari H. Eccrine adenocarcinoma. A clinicopathologic study of 35 cases. Arch Dermatol 1983;119:104–14. 3. Robson A, Greene J, Ansari N, et al. Eccrine porocarcinoma (malignant eccrine poroma): a clinicopathologic study of 69 cases. Am J Surg Pathol 2001;25:710–20. 4. Bardach H. Hidroacanthoma simplex with in situ porocarcinoma. A case suggesting malignant transformation. J Cutan Pathol 1978;5:236–48. 5. Anzai S, Arakawa S, Fujiwara S, Yokoyama S. Hidroacanthoma simplex: a case report and analysis of 70 Japanese cases. Dermatology 2005;210:363–5. 6. Lee JB, Oh CK, Jang HS, Kim MB, Jang BS, Kwon KS. A case of porocarcinoma from pre-existing hidroacanthoma simplex: need of early excision for hidroacanthoma simplex? Dermatol Surg 2003;29:772–4. 7. Wen SY. Case report of eccrine porocarcinoma in situ associated with eccrine poroma on the forehead. J Dermatol 2012; 39:649–51. 8. Wittenberg GP, Robertson DB, Solomon AR, Washington CV. Eccrine porocarcinoma treated with Mohs micrographic surgery: a report of five cases. Dermatol Surg 1999;25:911–3. 9. McMichael AJ, Gay J. Malignant eccrine poroma in an elderly AfricanAmerican woman. Dermatol Surg 1999;25:733–5. 10. Vleugels FR, Girouard SD, Schmults CD, et al. Metastatic eccrine porocarcinoma after Mohs micrographic surgery: a case report. J Clin Oncol 2012;30:e188–91.
Keith Duffy, MD Department of Dermatology and Huntsman Cancer Institute University of Utah Salt Lake City, Utah The authors have indicated no significant interest with commercial supporters.
Imaging of Desmoplastic Trichoepithelioma by High-Definition Optical Coherence Tomography Desmoplastic trichoepithelioma (DTE) is a rare benign adnexal tumor with follicular differentiation that appears most frequently on the face of young women. It can clinically mimic a variety of skin tumors such as intradermal nevus, sebaceous hyperplasia, and basal cell carcinoma (BCC).1 Because of its overlapping clinical features, the diagnosis of DTE is usually established on histopathology. However, given the
522
predilection of DTE on cosmetically sensitive areas on the face, the indication for biopsy should be as accurate as possible. Several noninvasive imaging techniques have emerged in recent years, aiming for higher accuracy of in vivo diagnosis. These include dermoscopy, reflectance confocal microscopy (RCM), and conventional optical coherence tomography (OCT). High-definition (HD) OCT (Skintell; Agfa
DERMATOLOGIC SURGERY
© 2015 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
hidroacanthoma simplex, also known as porocarcinoma in situ, is a rare slow-growing tumor that rarely metastasizes. Clinically, it appears similar to a seborrheic keratosis or Bowen disease and is often misdiagnosed until biopsy. However, hidroacanthoma simplex with dermal invasion is regarded as porocarcinoma, which has a less favorable prognosis and higher chance of metastasis.1 Malignant transformation of hidroacanthoma simplex can occur, and dermatologists also must monitor for progression to invasive porocarcinoma.1 A study by Anzai et al2 reported malignant transformation in 10% of their 70 cases. Early excision or MMS has been suggested even for the benign form of hidroacanthoma simplex because of the risk for malignant transformation.1 To the best of the authors’ knowledge, there are no reports of using MMS to treat malignant hidroacanthoma simplex, as the literature thus far only discusses conventional surgical excision for this neoplasm, without defined surgical margins. In the 3 articles that reported recurrence rates after performing conventional surgical excision, there was no recurrence at average 34 months.1,3,4 Mohs micrographic surgery has shown to be a very effective therapy for a number of contiguous malignant cutaneous tumors and has been successfully used in few cases of porocarcinoma as well.5 In treating porocarcinomas, MMS compared favorably with wide local excision with no local recurrences for as long as 60-month follow-up. In this case, given that the patient was immunocompromised (chronic lymphocytic leukemia) and the in situ tumor was located on the scalp, MMS was recommended when following the guidelines of the Mohs Appropriate Use Criteria for an equivalent tumor such as squamous cell carcinoma in situ. The surgery emphasized the need
for MMS, given that it involved 4 stages with approximately 3-cm margins to clear the tumor, despite a small preclinical appearance. In conclusion, this case adds to the literature of this rare malignant neoplasm and showcases MMS as another effective treatment option for this tumor, especially in areas where tissue sparing is paramount.
References 1. Lee JB, Oh CK, Jang HS, Kim MB, et al. A case of porocarcinoma from pre-existing hidroacanthoma simplex: need of early excision for hidroacanthoma simplex? Dermatol Surg 2003;29:772–4. 2. Anzai S, Arakawa S, Fujiwara S, Yokoyama S. Hidroacanthoma simplex: a case report and analysis of 70 Japanese cases. Dermatology 2005;210:363–5. 3. Piqué E, Olivares M, Espinel ML, Fariña M, et al. Malignant hidroacanthoma simplex. A case report and literature review. Dermatology 1995;190:72–6. 4. Lu X, Wu M, Chen J, Wu J, et al. A case of hidroacanthoma simplex. Indian J Dermatol 2013;58:245. 5. Wildemore JK, Lee JB, Humphreys TR. Mohs surgery for malignant eccrine neoplasms. Dermatol Surg 2004;30:1574–9.
Nita Kohli, MD, MPH Department of Dermatology University Hospitals Case Medical Center Case Western Reserve University Cleveland, Ohio Silvia Soohyun Kim, MD Shang I. Brian Jiang, MD Department of Dermatology University of California, San Diego San Diego, California The authors have indicated no significant interest with commercial supporters.
Commentary on Malignant Hidroacanthoma Simplex Treated With Mohs Surgery The author reads the article entitled “Malignant hidroacanthoma simplex treated with Mohs surgery” by Kohli and colleagues1 with great interest. This is an important “rare” nonmelanoma skin cancer that many Mohs surgeons will see in the span of their career, and
520
Mohs surgeons should be aware of the clinical presentation, nosology, histology, and treatment options. The classification, subclassification, and terminology of these eccrine neoplasms have been the subject of much
DERMATOLOGIC SURGERY
© 2015 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
LETTERS AND COMMUNICATIONS
debate in the dermatopathology literature over the last many decades. At present, it is generally accepted among dermatopathologists that there exists a group of eccrine neoplasms collectively referred to as poromas. These are further subdivided into eccrine poroma (epidermal and dermal components of poroma), dermal duct tumor (dermal eccrine poroma), and hidroacanthoma simplex (intraepidermal eccrine poroma). Less commonly encountered eccrine neoplasms also include syringoacanthoma and syringofibroadenoma. The malignant counterparts are broadly termed eccrine carcinomas but specifically are termed porocarcinoma and malignant hidroacanthoma simplex (or porocarcinoma in situ). These entities are the eccrine neoplasms that most dermatologic surgeons are likely to be asked to treat, particularly with Mohs micrographic surgery. In the larger series of eccrine carcinomas published,2,3 very few cases have been in situ variants (malignant hidroacanthoma simplex), and as such, the natural history of these carcinomas is not well defined. The author, however, assumes that these lesions will behave like squamous cell carcinoma in situ and given time they may acquire invasive and malignant potential. In the case presented by Kohli and colleagues, the clinical margins were quite indistinct and required 4 stages of micrographic surgery to be cleared. The clinically
indistinct margins in this case further suggest that Mohs micrographic surgery was appropriate as it would have been in a similar case of squamous cell carcinoma in situ. In regards to benign eccrine neoplasms, there is literature demonstrating malignant transformation of hidroacanthoma simplex4–6 and other poromas,7 and thus, a strong argument can be made for complete sampling of seemingly benign eccrine neoplasms. Anzai and colleagues5 report in their series of 70 cases of hidroacanthoma simplex in the Japanese population that 10% progressed to eccrine carcinoma. Given these data, it is reasonable to perform complete excisions of these lesions to assure appropriate sampling and prevent recurrence. Both the benign and malignant variants of eccrine neoplasms are clinically heterogeneous.3 Many eccrine neoplasms are clinically mistaken for seborrheic keratosis, squamous cell carcinoma in situ (Bowen disease), basal cell carcinoma, or pyogenic granuloma. The author has personally treated a case that was clinically thought to be seborrheic keratosis, but the pathology represented malignant hidroacanthoma simplex (porocarcinoma in situ). The case treated by the author arose in a 73-year-old Indian female who had a lesion present on her
Figure 1. (A) 5.0- · 3.0-cm plaque resembling large seborrheic keratosis. The defect (B) after diagnosis of porocarcinoma in situ and 2 stages of Mohs micrographic surgery. (C) Low-power (·40) of the histology demonstrating expansion of the epidermis with crowding of cells and numerous ductal structures. (D) Higher power (·400) with numerous apoptotic and mitotic cells with demonstration of many small luminal ducts.
41:4:APRIL 2015
521
© 2015 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
LETTERS AND COMMUNICATIONS
abdomen for 9 years with recent slow growth (Figure 1). She presented with a 5.0- · 3.0-cm verrucous plaque with complaints of itching and bleeding. Biopsy revealed an atypical poroid neoplasm with mitotic and apoptotic activity and ductal differentiation consistent with porocarcinoma in situ (Figure 1). The tumor was cleared with 2 stages of Mohs surgery. The debulk specimen was sectioned and did not contain any evidence of invasive disease. The lymph node examination was normal, and the patient has had no recurrence of the tumor after 12 months of follow-up. This case is similar to that presented by Kohli and colleagues and further reinforces both the index of suspicion needed for biopsy of these lesions and the effectiveness of Mohs surgery for treating these lesions. Ultimately, as dermatologic surgeons, we are attempting to treat carcinomas at early stages to prevent invasive disease and extensive locoregional spread. Not much literature exists regarding treatment of porocarcinomas with Mohs surgery,8,9 and in these small series, Mohs surgery seems to have been successful in treating local disease. Invasive porocarcinoma in the largest series of 54 patients with follow-up2 had 9 (17%) develop local recurrence, 10 (19%) develop nodal disease, and 6 (11%) develop distant metastases or death. A case of metastatic disease after Mohs surgery has been reported,10 with metastatic disease occurring 2 years after initial clear margins by Mohs surgery. This case serves as a reminder of the potential for these tumors to cause significant morbidity and mortality. As the author says to his residents, “Always respect the squamous cell carcinoma.” The same can be said for rare forms of skin cancer such as
porocarcinoma, which given time, can also be destructive and potentially deadly.
References 1. Kohli N, Soohyun Kim S, Brian Jiang SI. Malignant hidroacanthoma simplex treated with Mohs surgery. Dermatol Surg 2015;41:518–520. 2. Mehregan AH, Hashimoto K, Rahbari H. Eccrine adenocarcinoma. A clinicopathologic study of 35 cases. Arch Dermatol 1983;119:104–14. 3. Robson A, Greene J, Ansari N, et al. Eccrine porocarcinoma (malignant eccrine poroma): a clinicopathologic study of 69 cases. Am J Surg Pathol 2001;25:710–20. 4. Bardach H. Hidroacanthoma simplex with in situ porocarcinoma. A case suggesting malignant transformation. J Cutan Pathol 1978;5:236–48. 5. Anzai S, Arakawa S, Fujiwara S, Yokoyama S. Hidroacanthoma simplex: a case report and analysis of 70 Japanese cases. Dermatology 2005;210:363–5. 6. Lee JB, Oh CK, Jang HS, Kim MB, Jang BS, Kwon KS. A case of porocarcinoma from pre-existing hidroacanthoma simplex: need of early excision for hidroacanthoma simplex? Dermatol Surg 2003;29:772–4. 7. Wen SY. Case report of eccrine porocarcinoma in situ associated with eccrine poroma on the forehead. J Dermatol 2012; 39:649–51. 8. Wittenberg GP, Robertson DB, Solomon AR, Washington CV. Eccrine porocarcinoma treated with Mohs micrographic surgery: a report of five cases. Dermatol Surg 1999;25:911–3. 9. McMichael AJ, Gay J. Malignant eccrine poroma in an elderly AfricanAmerican woman. Dermatol Surg 1999;25:733–5. 10. Vleugels FR, Girouard SD, Schmults CD, et al. Metastatic eccrine porocarcinoma after Mohs micrographic surgery: a case report. J Clin Oncol 2012;30:e188–91.
Keith Duffy, MD Department of Dermatology and Huntsman Cancer Institute University of Utah Salt Lake City, Utah The authors have indicated no significant interest with commercial supporters.
Imaging of Desmoplastic Trichoepithelioma by High-Definition Optical Coherence Tomography Desmoplastic trichoepithelioma (DTE) is a rare benign adnexal tumor with follicular differentiation that appears most frequently on the face of young women. It can clinically mimic a variety of skin tumors such as intradermal nevus, sebaceous hyperplasia, and basal cell carcinoma (BCC).1 Because of its overlapping clinical features, the diagnosis of DTE is usually established on histopathology. However, given the
522
predilection of DTE on cosmetically sensitive areas on the face, the indication for biopsy should be as accurate as possible. Several noninvasive imaging techniques have emerged in recent years, aiming for higher accuracy of in vivo diagnosis. These include dermoscopy, reflectance confocal microscopy (RCM), and conventional optical coherence tomography (OCT). High-definition (HD) OCT (Skintell; Agfa
DERMATOLOGIC SURGERY
© 2015 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
