Competing Interest Statement Dr. Dale reports that he was a Founder of and holds equity in CorTechs Labs, Inc., and serves on its Scientific Advisory Board. He is a member of the Scientific Advisory Board of Human Longevity, Inc. He receives funding through research grants from GE Healthcare to UCSD. Dr. Rakow-Penner is a consultant for Human Longevity, Inc. and receives funding through research grants from GE Healthcare. The terms of these arrangements have been reviewed by and approved by UCSD in accordance with its conflict of interest policies. Dr. Igor Vidić is employed as a consultant for Cortechs Labs, Inc. Dr. Seibert reports personal honoraria in the past three years from Varian Medical Systems, Multimodal Imaging Services Corporation, and WebMD.

Sporotrichosis is a fungal infection known for its distinct pattern of infectious skin nodules. Several conditions can present with lesions that appear in a sporotrichoid pattern. An 82-year-old man that presented with three cutaneous nodules on his right leg in a sporotrichoid manner is described; biopsy of each lesion revealed a keratoacanthoma. In addition to keratoacanthomas, other neoplasms—albeit rarely—may be observed to occur in a sporotrichoid manner. These included squamous cell carcinoma (three patients), lymphoma (two patients), and one patient with each of the following: epithelioid sarcoma, Langerhans cell histiocytosis, melanoma, and peripheral nerve sheath tumor. The 10 patients whose cancer had cutaneous lesions that presented in a sporotrichoid distribution ranged from 28 to 83 years old. The tumors equally appeared on either the upper extremity (five patients) or the lower extremity (five patients). Treatments included systemic chemotherapy, surgical intervention, and radiation. Three of the patients died secondary to their tumors. In conclusion, various infections and some miscellaneous disorders can present in a sporotrichoid pattern. Keratoacanthomas can be added to the list of cancers (which include squamous cell carcinoma, lymphoma, epithelioid sarcoma, Langerhans cell histiocytosis, melanoma, and peripheral nerve sheath tumor) whose skin lesions have appeared in a sporotrichoid distribution. When cutaneous lesions appear in a sporotrichoid manner, biopsy of the tissue—for not only microscopic examination but also bacterial, fungal, and mycobacterial cultures—should be considered.

Basal cell carcinoma is the most common skin cancer. Pigmented basal cell carcinoma is an uncommon clinical presentation that can resemble a melanoma. We present the clinical and pathologic features of three individuals whose pigmented basal cell carcinomas masqueraded as melanomas. All of the patients were Hispanic and ranged in age from 63 years to 77 years. They presented with a pigmented lesion that was ultimately diagnosed as a pigmented basal cell carcinoma; one woman had a collision tumor consisting of a pigmented basal cell carcinoma and a seborrheic keratosis. All of the patients had their tumors removed using Mohs micrographic surgery, without recurrence. The clinical differential diagnosis of a black tumor―particularly in patients with darker skin types―should include pigmented basal cell carcinoma in addition to melanoma; a biopsy of the lesion will establish the diagnosis.

Background: The placement of a tattoo is a common event. Basal cell carcinoma arising from a tattoo is rare despite this neoplasm being the most common form of skin cancer. Objective: We describe a 41-year-old man who developed a basal cell carcinoma in his tattoo and review the literature of basal cell carcinomas originating in a tattoo. Methods: A literature search using PubMed was performed. The following terms were searched: “basal,” “carcinoma,” “cell,” and “tattoo.” The characteristics of individuals with a basal cell carcinoma originating in a tattoo were analyzed and summarized. Results: A total of 13 patients (6 women and 7 men) with a basal cell carcinoma arising in a tattoo have been reported. The majority of the tumors were located on the head (6 cases, 46.2%) followed by either an upper extremity (4 cases, 30.7%) or the trunk (3 cases, 23.1%). Most of the carcinomas were asymptomatic; however, 2 patients reported pruritus associated with their tumor. Nodular basal cell carcinoma was the most common subtype diagnosed (5 tumors), followed by superficial basal cell carcinoma (2 tumors). One patient had either a pagetoid or a mixed (nodular and sclerosing) histology. The pathological variant was not described for 4 patients. Conclusions: Basal cell carcinoma arising in a tattoo is a rare occurrence. Although this occurrence may be coincidental, emerging evidence of carcinogenesis associated with tattoo pigment may suggest a causal link. Elucidating this important relationship warrants further investigation.

Purpose: Diffusion-weighted magnetic resonance imaging (DW-MRI) is a contrast-free modality that has demonstrated ability to discriminate between pre-defined benign and malignant breast lesions. However, the ability of DW-MRI to discriminate cancer tissue from all other breast tissues on a voxel-level in a clinical setting is unknown. Here we explore the ability to distinguish breast cancer from healthy breast tissues using signal contributions from the newly developed three-component multi-b-value DW-MRI model. Experimental design: Pathology-proven breast cancer patients from two datasets (n=81 and n=25) underwent multi-b-value DW-MRI. The three-component signal contributions C1 and C2 and their product, C1C2, and signal fractions F1, F2 and F1F2 were compared to the image defined on maximum b-value (DWImax), conventional apparent diffusion coefficient (ADC), and apparent diffusion kurtosis (Kapp). Ability to discriminate between cancer and healthy breast tissues was assessed by the false positive rate given sensitivity of 80% (FPR80) and receiver operating characteristic (ROC) area under the curve (AUC). Results: Mean FPR80 for both datasets was 0.016 (95%CI=0.008-0.024) for C1C2, 0.136 (95%CI=0.092-0.180) for C1, 0.068 (95%CI=0.049-0.087) for C2, 0.466 (95%CI=0.428-0.503) for F1F2, 0.823 (95%CI=0.784-0.861) for F1, 0.172 (95%CI=0.146-0.197) for F2, 159 (95%CI=0.114-0.204) for DWImax, 0.731 (95%CI=0.692-0.770) for ADC and 0.684 (95%CI=0.660-0.709) for Kapp. Mean ROC AUC for C1C2 was 0.984 (95%CI=0.977-0.991). Conclusions: The three-component model yields a clinically useful discrimination between cancer and healthy breast tissues, superior to other DW-MRI methods and obliviating pre-defining lesions by radiologists. This novel DW-MRI method may serve as non-contrast alternative to standard-of-care dynamic contrast-enhanced MRI (DCE-MRI).