A practical classification scale for the dermatology management of individuals with skin of color: the colorimetric scale for skin of color.

A simple and rapid method that is not based on race and ethnicity for classifying people with skin of color is of paramount importance in dermatology. The currently used Fitzpatrick classification of sun-reactive skin types is inadequate. Newer scales that have been used in immigration surveys and sociology studies are not applicable in the office setting. A new, non-racial and non-ethnic, colorimetric scale for skin of color has recently been proposed that is simple to perform. The scale has five colors: very light beige (skin color type 1), light brown (skin color type 2), medium brown (skin color type 3), dark brown (skin color type 4) and very dark brown (skin color type 5); an individual with white skin, such as in albinism, would have a skin color type 0 in this classification. In conclusion, the colorimetric scale enables the rapid classification of individuals with skin of color and allows for accurate assessment of skin cancer risk, more appropriate management of cosmetic dermatologic procedures and aesthetic devices, and enhanced ability for focused counseling regarding hair products, skin care interventions, and color-targeted makeup based on the person's skin tone.

Cutaneous Superficial Basal Cell Carcinoma is a Basal Cell Carcinoma In Situ: Electron Microscopy of a Case Series of Basal Cell Carcinomas.

Basal cell carcinoma (BCC) is the most common skin cancer. Skin cancers may present either as a non-invasive tumor or an invasive malignancy. The terminology of carcinoma in situ is used when the tumor is either just limited to epidermis or not present as single cells or nests in the dermis. However, currently the terminology superficial BCC is inappropriately used instead of BCC in situ when the skin cancer is limited to epidermis. In this study we compare the pathologic changes of superficial, nodular, and infiltrative BCCs using electron microscopy to identify the ultrastructural characteristics and validate the previously proposed terminology. Three cases of BCC (superficial BCC, nodular BCC, and infiltrative BCC) diagnosed by dermatopathologists at our institute were selected for review. Paraffin block tissues from these cases were sent for electron microscopy studies which demonstrated disruption of basal lamina in both nodular and infiltrative type of BCC, while it remains intact in BCC superficial type after extensive examination. Therefore, similar to other in situ skin cancers, there is no invasion of the neoplasm in superficial BCC into the dermis. Hence, the older term superficial BCC should be appropriately replaced with the newer terminology BCC in situ.

Clinical features of atypical presentations of mucocutaneous herpes simplex virus infection observed in immunosuppressed individuals. Part II: the knife-cut sign.

The knife-cut sign is a distinctive manifestation of herpes simplex virus (HSV) type 1 or HSV type 2 infection that has been described in at least 10 immunocompromised patients. It appears as an extremely painful linear erosion or fissure in an intertriginous area such as the body folds beneath the breast, or within the abdomen, or in the inguinal region. Also, concurrent HSV infection at other mucocutaneous sites, or viscera, or both have been observed. The patients had medical conditions (at least 9 patients) and/or immunosuppressive drug therapy (6 patients). The diagnosis of HSV infection was confirmed by viral culture (8 patients), biopsy (4 patients), direct fluorescence antibody testing (3 patients), immunohistochemistry staining (2 patients), polymerase chain reaction (2 patients), or Western blot serologic assay (1 patient). Knife-cut sign-associated HSV infection is potentially fatal; three patients died. However, clinical improvement or complete healing occurred in the patients who received oral valacyclovir (1 patient), or intravenous acyclovir (2 patients), or intravenous acyclovir followed by foscarnet (1 patient). In summary, HSV infection associated with a positive the knife-cut sign is a potentially fatal variant of HSV infection that occurs in the intertriginous areas of immunocompromised patients and usually requires intravenous antiviral therapy.

Basal cell carcinoma in situ of the skin revisited: case reports of the superficial type and fibroepithelioma type of this in situ cutaneous neoplasm.

Cutaneous basal cell carcinoma in situ is a recently proposed subtype of this skin cancer. It is characterized by either restriction of the tumor cells within the epidermis or the presence of tumor cells contiguous with the overlying epidermis that extend into the underlying dermis, or both. Importantly, cancer invasion-demonstrated by non-contiguous aggregates of basaloid tumor cells in the dermis-is not a feature of in situ basal cell carcinoma of the skin. A 63-year-old woman with cutaneous basal cell carcinoma in situ-superficial type that presented as an erythematous scaly plaque on her abdomen and a 61-year-old man with a cutaneous basal cell carcinoma in situ-fibroepithelioma type that presented as a flesh-colored smooth exophytic nodule on his back are reported. The characteristics of in situ basal cell carcinoma of the skin in these individuals are summarized. In conclusion, similar to other cutaneous malignant neoplasms-such as squamous cell carcinoma, malignant melanoma, and Merkel cell carcinoma-basal cell carcinoma of the skin can also present as an in situ cancer.

Patients with a new-onset cutaneous sebaceous neoplasm following immunosuppression should be evaluated for Muir-Torre syndrome with germline mismatch repair gene mutation analysis: case reports.

Patients with Muir-Torre syndrome may have a systemic malignancy and a sebaceous neoplasm such as an adenoma, epithelioma, and/or carcinoma. The syndrome usually results from a germline mutation in one or more mismatch repair genes. Iatrogenic or acquired immunosuppression can promote the appearance of sebaceous tumors, either as an isolated event or as a feature of Muir-Torre syndrome and may unmask individuals genetically predisposed to the syndrome. Two iatrogenically immunosuppressed men with Muir-Torre syndrome features are described. Similar to these immunocompromised men, Muir-Torre syndrome-associated sebaceous neoplasms have occurred in solid organ transplant recipients, human immunodeficiency virus-infected individuals, and patients with chronic diseases who are treated with immunosuppressive agents. Muir-Torre syndrome-associated sebaceous neoplasms occur more frequently and earlier in kidney recipients, who are receiving more post-transplant immunosuppressive agents, than in liver recipients. The development of sebaceous neoplasms is decreased by replacing cyclosporine or tacrolimus with sirolimus or everolimus. Specific anti-cancer vaccines or checkpoint blockade immunotherapy may merit exploration for immune-interception of Muir-Torre syndrome-associated sebaceous neoplasms and syndrome-related visceral cancers. We suggest germline testing for genomic aberrations of mismatch repair genes should routinely be performed in all patients-both immunocompetent and immunosuppressed-who develop a Muir-Torre syndrome-associated sebaceous neoplasm.

Injected Drug Addiction-Associated Swollen Hands: A Case Report of Methylamphetamine-Related Unilateral Drug Addiction-Related Puffy Hand Syndrome.

Puffy hand syndrome occurs in addicts who have injected drugs either intravenously, intradermally, or subcutaneously. It usually presents as bilateral reversible pitting edema of the hands; less frequently, it occurs unilaterally. The forearms and arms may also be affected. The onset of puffy hand syndrome can occur while the patient is still injecting drugs; however, it can initially appear several years after injection of the drug has been discontinued. Infection with hepatitis C is a common comorbidity. A 47-year-old man is described who had a 20-year history of injecting methylamphetamine only into his non-dominant left arm, forearm, and hand and experienced his second episode of unilateral puffy hand syndrome four years after discontinuing injecting the drug and three years after his initial episode; he also had hepatitis C infection. He presented with erythema and pitting edema of his left hand and forearm. Cellulitis was initially suspected, and he was admitted to the hospital for intravenous antibiotics; all cultures were negative for pathogens. The erythema and swelling resolved after five days of therapy. Puffy hand syndrome has been associated with various drugs; it has also been observed to occur in women during pregnancy and occasionally associated with acrocyanosis. The diagnosis is often not originally entertained by the clinician; the condition is often initially treated empirically as an infection. Serologic evaluation is typically negative for rheumatologic diseases, such as systemic lupus erythematosus and scleroderma, and cultures of the skin and blood are usually negative for pathogens. Radiologic assessment (such as roentgenograms, ultrasound to rule out venous thrombosis, computed tomography, magnetic resonance imaging, venogram, and lymphangiogram) may be performed, to exclude other conditions. Skin biopsy of the affected edematous hand occasionally demonstrates granulomatous inflammation and foreign bodies (suggestive of starch or injection additives) in the dermis. The edema for some of the patients with puffy hand syndrome was successfully treated with daily bandaging with compression stockings. The pathogenesis of puffy hand syndrome is considered to be multifactorial: damage to the veins, injury to the lymphatic system, and direct toxicity of the injectable drugs to the vascular structures.

Neuregulin-1 and ALS19 (ERBB4): at the crossroads of amyotrophic lateral sclerosis and cancer.

BACKGROUND: Neuregulin-1 (NRG1) is implicated in both cancer and neurologic diseases such as amyotrophic lateral sclerosis (ALS); however, to date, there has been little cross-field discussion between neurology and oncology in regard to these genes and their functions. MAIN BODY: Approximately 0.15-0.5% of cancers harbor NRG1 fusions that upregulate NRG1 activity and hence that of the cognate ERBB3/ERBB4 (HER3/HER4) receptors; abrogating this activity with small molecule inhibitors/antibodies shows preliminary tissue-agnostic anti-cancer activity. Notably, ERBB/HER pharmacologic suppression is devoid of neurologic toxicity. Even so, in ALS, attenuated ERBB4/HER4 receptor activity (due to loss-of-function germline mutations or other mechanisms in sporadic disease) is implicated; indeed, ERBB4/HER4 is designated ALS19. Further, secreted-type NRG1 isoforms may be upregulated (perhaps via a feedback loop) and could contribute to ALS pathogenesis through aberrant glial cell stimulation via enhanced activity of other (e.g., ERBB1-3/HER1-3) receptors and downstream pathways. Hence, pan-ERBB inhibitors, already in use for cancer, may be agents worthy of testing in ALS. CONCLUSION: Common signaling cascades between cancer and ALS may represent novel therapeutic targets for both diseases.

Colorimetric Scale for Skin of Color: A Practical Classification Scale for the Clinical Assessment, Dermatology Management, and Forensic Evaluation of Individuals With Skin of Color.

Skin of color refers to individuals whose skin color ranges from very light beige to very dark brown. Anthropologists and sociologists have previously recognized the importance of an objective classification of skin color for individuals with skin of color that does not include race and ethnicity. Since 1975, dermatologists have used the Fitzpatrick classification of sun-reactive skin types to categorize patients with skin of color; this classification was established for psoriasis patients participating in using oral methoxsalen and phototherapy clinical trial to determine the initial ultraviolet A dose. The Fitzpatrick classification merely classifies individuals as white, brown, and black; the individuals with white skin are further divided into four groups based on their burning or tanning capacity. This classification system does not provide reliable information with regard to the risk of skin cancer for individuals with darker skin color and does not aid in the evaluation of medical conditions with cutaneous involvement or assessment of appropriate cosmetic interventions for aesthetic management. Many clinicians, including forensic pathologists, incorporate the patient's race or ethnicity in their medical evaluation to describe the individual's skin color. Established scales for skin of color either include white skin color, or include 10 or more color types, or include both. We introduce a simple and rapidly performed scale that is not based on race or ethnicity to categorize persons with skin of color. The colorimetric scale ranges from very light beige to very dark brown and does not include white skin. The scale has five colors ranging from lightest (skin color type 1) to darkest (skin color type 5): very light beige (skin color type 1), light brown (skin color type 2), medium brown (skin color type 3), dark brown (skin color type 4), and very dark brown (skin color type 5); an individual with white skin would have a skin color type 0 in this classification of patient skin color. In conclusion, a scale that is not based on race or ethnicity is useful for categorizing individuals with skin of color not only for sociologists but also for clinicians who treat these patients. This colorimetric scale will be helpful for dermatologists to categorize persons with skin of color to predict their risk for developing skin cancer and to assessing appropriate cosmetic procedures and devices for these patients. In addition, the colorimetric scale will be useful for not only forensic pathologists but also other clinicians to provide a non-racial and non-ethnic designation of skin color type for their patients.

ALPK1 mutants causing ROSAH syndrome or Spiradenoma are activated by human nucleotide sugars.

The atypical protein kinase ALPK1 is activated by the bacterial nucleotide sugar ADP-heptose and phosphorylates TIFA to switch on a signaling pathway that combats microbial infection. In contrast, ALPK1 mutations cause two human diseases: the ALPK1[T237M] and ALPK1[Y254C] mutations underlie ROSAH syndrome (retinal dystrophy, optic nerve oedema, splenomegaly, anhidrosis, and migraine headache), while the ALPK1[V1092A] mutation accounts for 45% of spiradenoma and 30% of spiradenocarcinoma cases studied. In this study, we demonstrate that unlike wild-type (WT) ALPK1, the disease-causing ALPK1 mutants trigger the TIFA-dependent activation of an NF-κB/activator protein 1 reporter gene in the absence of ADP-heptose, which can be suppressed by either of two additional mutations in the ADP-heptose binding site that prevent the activation of WT ALPK1 by ADP-heptose. These observations are explained by our key finding that although ALPK1[T237M] and ALPK1[V1092A] are activated by bacterial ADP-heptose, they can also be activated by nucleotide sugars present in human cells (UDP-mannose, ADP-ribose, and cyclic ADP-ribose) which can be prevented by disruption of the ADP-heptose binding site. The ALPK1[V1092A] mutant was also activated by GDP-mannose, which did not activate ALPK1[T237M]. These are new examples of disease-causing mutations permitting the allosteric activation of an enzyme by endogenous molecules that the WT enzyme does not respond to. We propose that the loss of the specificity of ALPK1 for bacterial ADP-heptose underlies ROSAH syndrome and spiradenoma/spiradenocarcinoma caused by ALPK1 mutation.

Linea Nigra: Case Report of a Woman With a Pregnancy-Associated Linear Streak of Cutaneous Hyperpigmentation on Her Abdomen From the Umbilicus to the Pubic Symphysis.

Linea nigra is a distinctive presentation of asymptomatic cutaneous hyperpigmentation on the abdomen that usually extends from the umbilicus to the pubic symphysis. It is frequently observed as a physiologic change associated with pregnancy. A primigravida 19-year-old woman began to develop skin darkening during week 24 of gestation. She delivered a healthy infant. Three months postpartum, the hyperpigmentation had not resolved. After the benign characteristics of her cutaneous hyperpigmentation were explained, the patient decided to clinically monitor the dark linear streak. Similar to this patient, clinical studies of pregnant women have observed the incidence of pregnancy-associated linea nigra to range from 32% to 92%; in contrast to this woman, partial or complete spontaneous resolution of the skin darkening commonly occurs after delivery of the newborn. During gestation, the development of linea nigra has been postulated to be caused by elevated estrogen, progesterone, and/or melanocyte-stimulating hormone levels. Linea nigra is not restricted to gestational females; it has also been noted in newborns and children. In addition, it has also been observed in men who had either benign prostate hyperplasia or prostate cancer. In summary, linea nigra is often an acquired longitudinal streak of benign cutaneous hyperpigmentation on the abdomen; when linea nigra is pregnancy-associated, the skin darkening often partially or completely resolves, spontaneously after delivery.

Tomato Plant-Associated Xanthoderma: Case Report and Review of Exogenous Causes of Yellow Skin.

The skin, hair, and nails can all present with yellow discoloration secondary to exogenous etiologies. Xanthoderma, yellow discoloration of the skin, can occur not only from exogenous sources secondary to topical contact with various substances but also from endogenous causes such as diseases from the liver and kidney, or oral medications. A 64-year-old man developed asymptomatic, yellow staining of his distal left forearm, hand, and fingertips. He was not receiving antimalarials, did not have hepatic or renal dysfunction, and had not applied any sunless tanning solutions to his skin. Prior to the appearance of his xanthoderma, he had been tending to a tomato plant in his yard; the yellow staining appeared on the areas of his left upper extremity that had contacted the stems and leaves of the tomato plant. Within two days, the yellow skin discoloration resolved spontaneously after several washings of the affected areas with soap and water. Tomato plants have trichomes that appear as hair-like structures on the stems and produce an oily substance; the trichomes not only produce the scent of the plant, but also provide protection from cold, drought, disease, and pests. Initially, when the oily substance contacts the skin, the skin appears yellow; subsequently, the skin may become black. The skin that has been stained by a tomato plant is referred to as "tomato skin" (TOMASK). In addition to reviewing the etiology of exogenous xanthoderma, this paper also summarizes the causes of exogenous yellow hair and yellow nails. Exogenous yellowing of the skin can result from various topical causes. Common topical etiologies of xanthoderma include not only contact with tomato plants, but also sunless tanning solutions (that contain dihydroxyacetone) and tobacco (that not only causes yellow staining of the white hair on men's upper lip referred to as "smoker's mustache", but also yellow staining of the nail plate and fingertips used to hold the cigarette or cigar). In summary, tomato plant-associated xanthoderma is a benign exogenous etiology of yellow staining of the skin which eventually resolves after several washings of the affected sites with soap and water.

Cornu Cutaneum: Case Reports of Patients With a Cutaneous Horn Associated With Either a Verruca Vulgaris or an Inverted Follicular Keratosis and a Review of the Etiologies of Cutaneous Horns.

A cutaneous horn, referred to as a cornu cutaneum in Latin, presents as a mound of keratinizing epithelium. The etiology of the cutaneous horn is associated with the lesion at its base. In addition to numerous benign and malignant neoplasms, cutaneous horns may be related to infections and skin conditions. The features of a 22-year-old woman with a cutaneous horn associated with a recalcitrant verruca vulgaris on her left fifth toe are described. In addition, the characteristics of a 57-year-old man with an inverted follicular keratosis-related cutaneous horn on his upper lip are reported. In order of decreasing frequency, a cutaneous horn is most associated with either an actinic keratosis (25%), a squamous cell carcinoma (19%), a seborrheic keratosis (19%-20%), or a verruca vulgaris (18%). Adnexal neoplasms, epithelial lesions, fibrous lesions, granular cell tumors, hamartomas, histiocytic lesions, melanocytic nevus, premalignant keratoses, a subungual lesion, and vascular lesions comprise the benign neoplasms that have been observed at the base of a cutaneous horn. Dermatologic conditions that have been associated with a cutaneous horn include discoid lupus erythematosus (three patients) and one patient with either palmoplantar keratoderma, psoriasis, or sarcoidosis. Human papillomavirus infection presenting as a verruca vulgaris is the most commonly associated infection; pox virus-related molluscum contagiosum is another viral infection that is less often observed associated with a cutaneous horn. Leishmaniasis, rhinosporidiosis, and cutaneous tuberculosis are rare cutaneous horn-related infections. A malignant tumor-associated cutaneous horn is most frequently caused by squamous cell carcinoma; other less common cancers include basal cell carcinoma, sebaceous carcinoma, verrucous carcinoma, and malignant melanoma. A cancer-related cutaneous horn has only been described in two patients with Kaposi sarcoma and one patient with either Merkel cell carcinoma or Paget disease of the breast or metastatic renal cell carcinoma. In summary, a cutaneous horn is potentially related to a tumor, an infection, or a skin disorder; an adequate evaluation of the base of the cutaneous horn is usually required to establish the associated diagnosis.

Halo Phenomenon in Lobular Capillary Hemangioma: A Case Report of a Pyogenic Granuloma With Surrounding Cutaneous Hypopigmentation and Review of Tumors With Halo Phenomenon.

A halo phenomenon describes a skin neoplasm that is surrounded by a hypopigmented or white halo. Halo lesions have been observed in association with an epithelial neoplasm (seborrheic keratosis), a fibrous lesion (surgical scar), a keratinocyte malignancy (basal cell carcinoma), melanocytic neoplasms, and vascular lesions. Benign lesions (café au lait macules and nevi) and malignant tumors (primary and metastatic melanoma) are melanocytic neoplasms that have developed perilesional halos. Halo nevi are a commonly occurring manifestation of a halo phenomenon; however, perilesional hypopigmented halos have also been observed around nevi in patients following treatment with antineoplastic drugs, acquisition of COVID-19 (infection and vaccine), the occurrence of a visceral tumor (including not only melanoma, but also papillary thyroid carcinoma and neuroendocrine cancer of the lung), surgery (such as the excision of a primary melanoma), and Turner syndrome. A halo phenomenon has also been observed in patients with congenital (capillary malformation-arteriovenous malformation and congenital hemangioma) or acquired (angioma, eruptive pseudoangiomatosis, infantile hemangioma, and lobular capillary hemangioma) vascular lesions. In summary, a halo phenomenon can occur in association with primary lesions of various embryologic derivations. Most commonly, they have been observed in around nevi and vascular tumors. Halo lobular capillary hemangioma can be added to the list of acquired vascular lesions with the potential to develop a halo phenomenon. The preservation of melanocytes with loss of melanin pigment expression in the reported patient suggests the possibility that a post-inflammatory etiology may be responsible for the genesis of her halo lobular capillary hemangioma.

Ligamentum teres cardiopexy for post vertical sleeve gastrectomy gastroesophageal reflux.

PURPOSE: Vertical sleeve gastrectomy (VSG) evolved in the early 2000s into the standalone weight loss procedure we see today. While numerous studies highlight VSG's durability for weight loss, and improvements co-morbidities such as type 2 diabetes mellitus and cardiovascular disease, patients with gastroesophageal reflux disease (GERD) have been counseled against VSG due to the concern for worsening reflux symptoms. When considering anti-reflux procedures, VSG patients are unable to undergo traditional fundoplication due to lack of gastric cardia redundancy. Magnetic sphincter augmentation lacks long-term safety data and endoscopic approaches have undetermined longitudinal benefits. Until recently, the only option for patients with a history of VSG with medically refractory GERD has been conversion to roux en Y gastric bypass (RNYGB), however, this poses other risks including marginal ulcers, internal hernias, hypoglycemia, dumping syndrome, and nutritional deficiencies. Given the risks associated with conversion to RNYGB, we have adopted the ligamentum teres cardiopexy as an option for patients with intractable GERD following VSG. METHODS: A retrospective chart review was conducted of patients who had prior laparoscopic or robotic VSG and subsequently GERD symptoms refectory to pharmacological management who underwent ligamentum teres cardiopexy between 2017 and 2022. Pre-operative GERD disease burden, intraoperative cardiopexy characteristics, post-operative GERD symptomatology and changes in H2 blocker or PPI requirements were reviewed. RESULTS: Of the study's 60 patients the median age was 50 years old, and 86% were female. All patients had a diagnosis of GERD through pre-operative assessments and were taking antisecretory medication. Of the 36 patients who have completed their one year follow up, 81% of patients had either a decrease in dosage or cessation of the antisecretory medication at one year following ligamentum teres cardiopexy. CONCLUSION: Ligamentum teres cardiopexy is a viable alternative to RNYGB in patients with a prior vertical sleeve gastrectomy with medical refractory GERD.

Glomus Extradigital Tumor: A Case Report of an Extradigital Glomus Tumor on the Wrist and Comprehensive Review of Glomus Tumors.

A glomus tumor is a neoplasm composed of cells from the glomus body which is a contractile neuromyoarterial structure that affects blood pressure and thermoregulation by altering cutaneous blood flow. This cutaneous tumor can be benign or rarely malignant, solitary or multiple, and digital or extradigital. A benign glomus tumor usually presents as a non-familial, solitary, and subungual lesion. Multiple glomus tumors are less common, may be autosomal dominantly inherited, and extradigital. In contrast to a digital glomus tumor that often occurs within the nailbed or fingertip pulp of a young woman, a glomus extradigital tumor (GET) typically appears on the extremity or trunk of an older man. The diagnosis of a glomus tumor may be suspected based on clinical evaluation; it classically presents with a clinical triad of symptoms which includes lesion-associated tenderness, pin-point pressure pain, and cold sensitivity. However, cold-induced exacerbation of pain is frequently absent in extradigital glomus tumors; this may contribute to a delay in establishing the diagnosis of a glomus tumor in these individuals. Radiographic studies can support the diagnosis, but tissue specimen examination is necessary to establish the diagnosis. Resolution of tumor-associated pain is usually achieved following the complete excision of the neoplasm. A woman with a glomus tumor located on her wrist is described; her painful tumor was not sensitive to cold and was misdiagnosed clinically as a possible foreign body reaction to either a wood splinter or glass shard. The diagnosis of an extradigital glomus tumor was established after a microscopic examination of the tissue specimen following an excisional biopsy using a 3-millimeter punch biopsy tool. The neoplasm-related pain ceased and did not recur after the tumor had been completely removed. In conclusion, a glomus tumor is included in the differential diagnosis of a painful cutaneous neoplasm; however, misdiagnosis and/or substantial delay in diagnosis may occur if the tumor is extradigital or it lacks cold sensitivity or both. Therefore, the clinician needs to entertain the possibility of an extradigital glomus tumor when evaluating a patient with a tender, temperature-insensitive skin lesion that is not located on the fingers or toes.

Mobile Subcutaneous Calcinosis Cutis: A Case Report of a Mobile Solitary Subepidermal Calcified Nodule on a Woman's Leg and a Review of Mobile Subcutaneous Tumors.

Calcinosis cutis describes the deposition of calcium in the dermis. A case of a 69-year-old woman with idiopathic calcinosis cutis that presented as a mobile subcutaneous nodule is described. The patient had an asymptomatic, firm, mobile subcutaneous nodule on her right lower leg of at least six months duration. The nodule could be easily moved from one location to another. An incisional biopsy was performed. Microscopic examination of the tissue specimen showed islands of basophilic calcium material in dense sclerotic dermal connective tissue establishing the diagnosis of calcinosis cutis. Mobile solitary calcification is an unusual presentation of idiopathic calcinosis cutis. In addition to idiopathic calcinosis cutis, benign mobile subcutaneous tumors have also been derived from adnexal structures of hair follicles and adipose tissue. Hence, not only idiopathic calcinosis cutis, but also subepidermal calcinosis in the ocular adnexa, proliferating trichilemmal cyst with focal calcification, and mobile encapsulated adipose tissue can present as a mobile subcutaneous nodule. The features of idiopathic calcinosis presenting as a mobile subcutaneous nodule as well as the characteristics of other benign mobile subcutaneous tumors are reviewed.