Azusa Ogita

Histopathological diagnosis of epithelial crateriform tumors: Keratoacanthoma and other epithelial crateriform tumors.

Keratoacanthoma (KA) is a unique and distinct clinicopathological entity, although there is often confusion regarding its differentiation from other types of crateriform tumors. In this study, the clinicopathological features of 380 epidermal crateriform tumors with a central keratin plug were re‐examined and the tumors were histologically classified into seven types: (i) crateriform verruca; (ii) crateriform seborrheic keratosis; (iii) KA; (iv) KA with a conventional squamous cell carcinoma (SCC) component (KA‐like SCC and KA with malignant transformation); (v) crateriform Bowens disease; (vi) crateriform SCC arising from solar keratosis; and (vii) crater form of infundibular SCC. Our study proved that incidence of SCC developing in KA lesions was 17.4%. The incidence rate differed depending on a patients ages: 8.3% in patients less than 70 years of age and 24.3% in those aged 70 years and older. Nearly all of the malignant crateriform neoplasms (94.7%) occurred on sun‐exposed areas. Lesions on the face included 138 KA (59.5%), 65 malignant crateriform neoplasms (28%) and 29 benign crateriform neoplasms (12.5%). We conclude that KA is not a variant of SCC, but a benign and frequently regressing proliferative lesion or borderline neoplasm, although there is the potential for SCC to arise within KA. Because the incidence of SCC developed in KA lesions and the incidence of other malignant crateriform neoplasms are higher in patients aged 70 years and older, KA‐like lesions on sun‐exposed areas over 70 should be assessed carefully in consideration of the potential risk of malignancy.

Clinicopathological study of crateriform verruca: Crateriform epithelial lesions histopathologically distinct from keratoacanthoma.

Keratoacanthoma (KA) is a distinct clinicopathological entity, but it is often confused with other crateriform tumors. This study re‐examined the clinicopathological features of 380 crateriform epithelial tumors with a central keratin plug. Seventy‐six tumors (20%) had histopathological features that differed from solitary KA and were more verruca‐like, and we designated these lesions as crateriform verruca (CFV). We performed clinicopathological re‐examination of these neoplasms with a crateriform architecture and epithelial lip‐like structures similar to KA, which also displayed histopathological features reminiscent of verruca vulgaris, such as finger‐like exophytic projections with hyperkeratosis and acanthosis, focal hypergranulosis and arborization. Clinical data on CFV were also summarized. The main histopathological differences from KA were that CFV showed proliferation of keratinocytes with a similar size and regular arrangement, and the base of CFV was well demarcated without endophytic growth. Interestingly, some CFV were partly composed of epithelial cells with large pink cytoplasm in the upper malpighian layer between papillomatous projections. Furthermore, areas of trichilemmal‐like keratinization without formation of the granular layer were seen in some lesions. These types of CFV were hardly distinguishable from KA, unless it is recognized that CFV may contain trichilemmal keratinization‐like areas accompanied by large epithelial cells with eosinophilic cytoplasm. We have proposed the term CFV for these verrucous neoplasms to differentiate them from KA.

Case of Merkel cell carcinoma with squamous cell carcinoma possibly arising in chronic radiodermatitis of the hand.

We report a case of Merkel cell carcinoma (MCC) on the dorsal aspect of the right middle finger associated with multiple squamous cell carcinomas (SCC) possibly arising in chronic radiation dermatitis of the hand of an 80‐year‐old surgeon. In spite of resection of the primary lesion and right axillary lymph nodes, he died of the tumor 5 months after the first visit. Cutaneous and lymph node lesions of MCC were negative for Merkel cell polyoma virus (MCPyV) by immunostaining using monoclonal antibody (CM2B4) and anti‐large T antigen of MCPyV polyclonal antibody, and real‐time polymerase chain reaction. Several differences in clinicopathological findings have been found between MCPyV‐positive cases and negative ones. Several authors have reported that MCPyV‐negative cases have a worse prognosis than MCPyV‐positive ones. Furthermore, in cases of MCC associated with SCC, most tumors have been reported to be MCPyV‐negative. We should pay more attention to the relationship between the carcinogenesis of MCC and ionizing irradiation.

Nodular-type lichen myxedematosus: a case report.

An 18-year-old Japanese woman noticed a progressive appearance of nodules on both forearms and on the left cubital fossa and left thigh one year before her initial consultation at our department. Physical examination showed elastic hard, slightly elevated, shiny and yellowish to skin-colored nodules of 6 to 10 mm in size on her extremities. From laboratory and histopathological findings, nodular-type lichen myxedematosus was diagnosed and nodules showed complete remission following local injection of triamcinolone acetonide.

Dermoscopic findings of microcystic adnexal carcinoma

Microcystic adnexal carcinoma (MAC) is an uncommon malignant cutaneous neoplasm differentiating towards the pilosebaceous apparatus. The number of case reports describing the dermoscopic findings of MAC has been very limited. We herein report a case of MAC, present the dermoscopic features of the case and compare them with those of desmoplastic trichoepithelioma (DTE), which often needs to be differentiated from MAC.A 52-year-old woman presented at our outpatient clinic with a lesion on her right [...]

Case of anaphylaxis due to tetracycline hydrochloride

A 17‐year‐old Japanese woman showed anaphylaxis after taking tetracycline hydrochloride, pyridoxal phosphate, flavin adenine dinucleotide sodium and ascorbic acid. Prick tests were performed for these suspicious drugs and anaphylaxis due to tetracycline hydrochloride was diagnosed.

Case of warty dyskeratoma on the anterior chest: The relationship between its dermoscopic and histopathological findings

Dear Editor, Warty dyskeratoma (WD) is a rare benign tumor that mainly presents as an isolated papule or nodule on the scalp or neck. The dermoscopic findings of WD have only been described in one case report. We report the findings of another case and the relationship between the dermoscopic and histopathological findings of WD. A 50-year-old man visited our hospital complaining of a 7-mm asymptomatic dark red nodule on his chest (Fig. 1a), which had gradually increased in size for 2 years. He was otherwise in good health. Dermoscopy revealed a red area surrounded by yellow regions, which corresponded to the central depression, and a transparent milky red doughnut-shaped area with several radially arranged thick whitish lines, which resembled a jellyfish or iris (Fig. 1b). The lesion was excised under local anesthesia. Histopathologically, the lesion exhibited a crateriform appearance consisting of a large, well-circumscribed region of epidermal invagination, whose periphery and base were mainly lined by proliferating epithelial cells, extending into the papillary dermis (Fig. 1c). The lesion also displayed a widely dilated follicular infundibulum, and acantholysis of the suprabasal keratinocytes was observed in the granular and horny layers. The epidermal invaginations were filled with keratinous material. The lower portion of each invagination contained suprabasal clefts and villi lined by a single layer of basaloid cells. Each invagination was partially covered by a parakeratotic plug, and many of them were surrounded by epidermal collarettes and hyperplastic epidermal tissue, which demonstrated hypergranulosis and papillomatosis. Typical corps ronds and grains were also noted. Perivascular infiltrates of lymphocytes and histiocytes were seen in the upper dermis (Fig. 1d). A diagnosis of WD was made based on these findings. Regarding the relationship between the dermoscopic and histopathological findings, the outer rim was found to be quite transparent during the dermoscopic examination, whereas histopathologically the lesion rose up from the papillary dermis; the red area within the central depression mainly reflected dilated blood vessels in the papillary dermis; the yellowish areas around the outside of the central red area corresponded

Case of syringomatous carcinoma with unique clinical presentation.

tic findings reflected histological cystic area and lobulated masses. In other words, skin ultrasonography can provide sonographic diagnosis of nodular hidradenoma before excision in advance. It is difficult to diagnose some intradermal or subcutaneous lesions without histopathological findings because they are invisible from the outside. Ultrasonography is an essential tool for most medical specialties. Ultrasonography is a versatile, painless, low-risk, non-invasive procedure which can be done anywhere and easily repeated. It provides real-time visual information about benign and malignant processes in the dermatological field as well as other fields. To date, the usefulness of ultrasonography for lipoma and epidermal cyst has been established. However, its usefulness for nodular hidradenoma has been so far unclear because skin ultrasound examination of nodular hidradenoma has been described in only a few reports. In previous published works, mass with irregular internal echo in the hypoechoic area has been reported as a common ultrasonographic feature. On the other hand, the power Doppler effect of the tumor varies from one case to another and remains poorly understood. At all events, this characteristic finding as an intracystic papillary lesion detected by ultrasonography can be a reliable one for diagnosing nodular hydradenoma. In conclusion, our case emphasizes that skin ultrasonography is a useful tool for predicting nodular hidradenoma before excision. This simple technique should be performed by dermatologists when clinical manifestations are not typical or characteristic in skin tumors. Further reports will be required.

Collision of basal cell carcinoma and melanocytic nevus with unique dermoscopic findings

Dear Editor, Dermoscopic examination is now an essential method for accurate diagnoses of pigmented skin lesions, especially neoplastic lesions. Dermoscopic findings of melanocytic nevi, malignant melanomas, seborrheic keratoses and basal cell carcinomas have been well documented. However, collision of these common lesions has not been frequently reported, so we may be puzzled when we encounter such lesions. We herein report a case of collision of basal cell carcinoma (BCC) and melanocytic nevus (MCN), especially focusing on the dermoscopic findings of the case. A 47-year-old woman visited our outpatient clinic complaining of a pigmented papule on her dorsal nose, which had been present for several years. Physical examination at first visit revealed an irregularly shaped pigmented papule 4.5 mm 9 5.5 mm in diameter (Fig. 1a). Dermoscopic examination revealed that the lesion consisted of a blue-gray structureless area with partly avoiding hair follicles at the upper left periphery, large blue-gray ovoid nests, spoke-wheel areas and leaf-like areas at the lower right part (Fig. 1b). We suspected BCC or MCN from those findings, and the lesion was resected with a 2-mm margin. Tissue sections were made according to the cutting lines shown in Figure 1(c). Histopathological findings of a resected section (1) revealed an elevated nodular lesion in the dermis composed of two different components (Fig. 1d). On the left side of the lesion, there were several tumor cell nests composed of basaloid cells with nuclei palisaded at the periphery and partly connected to the epidermis (Fig. 1e). These neoplastic cells were positive for Ber-EP4 (Fig. 1g). This part of the lesion was diagnosed as BCC. In the center of the lesion, cells with small nuclei and scant cytoplasm formed nests in the dermis (Fig. 1f). Some of them had melanin pigment in their cytoplasm. These tumor cells were positive for Melan-A (Fig. 1h). Accordingly, this part of the lesion was diagnosed as Miescher type MCN. These two parts were partially intermingled in the lesion, especially on the right side of the resected section 1. From the findings of this section (1) and other resected sections (2, 3), and dermoscopic findings, we speculated that the distribution of these two (a) (b)

Case of basosquamous carcinoma: Dermoscopic and immunohistochemical findings.

the general condition of the patient before treatment, monitored him closely when propranolol was given in the first 2 months, and the drug was administrated at 0.125 mg/kg per dose from the beginning. Although the patient had experienced myocardial enzyme level increase which was treated by oral fructose sodium diphosphate solution by our pediatric cardiologist, the side-effect was believed to be temporary and would not cause long-term adverse influence on the patient; thus, propranolol was used successfully without obvious sideeffects. In this case, a cautious and gradual approach in using propranolol for our preterm and low birthweight neonate with IH was adopted. A low initiation dose, gradual dose increase and close monitoring were employed and the patient was successfully treated.