Negative predictive value of biopsy margins of dysplastic nevi: A single-institution retrospective review

BACKGROUND

Biopsies of dysplastic nevi processed by bread-loafing allow for limited margin assessment; however, reported biopsy margins often influence management.

OBJECTIVE

To evaluate the negative predictive value of biopsy margins of dysplastic nevi.

METHODS

A retrospective search of a single academic institution's pathology database was conducted to identify all biopsy specimens of dysplastic nevi between January 1, 2015, and December 31, 2017. Biopsy specimen margin assessments were compared with excision pathology reports to calculate negative predictive value and to assess the frequency of residual nevus on excision after positive biopsy margins.

RESULTS

A total of 1245 dysplastic nevi from 934 patients were identified. Clear biopsy margins had a negative predictive value for the absence of residual nevus on excision of 87.3% for dysplastic nevi of moderate atypia or greater. Residual nevus was identified on excision in 29.41% of cases of dysplastic nevi of moderate atypia or greater when initial biopsy margins were positive.

LIMITATIONS

This was a retrospective, single-institution study. The calculations likely overestimate the true negative predictive value of biopsy margins because of processing of excision specimens by bread-loafing.

CONCLUSIONS

This study provides additional evidence that reported biopsy margins are not representative of true margin status.

Pediatric ocular lichen planus and lichen planopilaris: One new case and a review of the literature

When lichen planus involves the scalp, it is known as lichen planopilaris, and when it involves the eye, it is known as ocular lichen planus; both are rare. Early detection and targeted therapy are crucial in preventing hair loss and scarring conjunctivitis. Little is known regarding appropriate treatment for lichen planopilaris. The objective of this case study is to present a new case of pediatric ocular lichen planus and lichen planopilaris and to identify all reported cases of pediatric lichen planopilaris, highlighting disease involvement, treatment, and response to treatment.

Chronic granulomatous dermatitis induced by talimogene laherparepvec therapy of melanoma metastases

Talimogene laherparepvec (TVEC) is the first oncolytic viral immunotherapy approved by the FDA, for advanced melanoma consisting of genetically modified herpes simplex type 1 virus which selectively replicates causing tumor lysis, expressing granulocyte macrophage-colony stimulating factor (GM-CSF) and activating dendritic cells. Intratumoral injection of TVEC produces objective response in 41% of stage IIB-IV M1a melanoma. However, clinical response assessment can be problematic due to immune-related inflammation at established tumor sites. Herein, we report 5 cases of granulomatous dermatitis developing at sites of TVEC injection associated with pathologic complete response in 4 of 5 patients. Over 5 months, TVEC injections were administrated in a median of 20 tumors per patient for 9 median doses prior to biopsy of persistent, indurated nodules. Granulomatous dermatitis with melanophages and melanin pigment incontinence was observed in all samples without evidence of melanoma cells in 4 patients. The fifth patient was rendered melanoma-free by resection of the 1 nodule out of 4 with persistent tumor. Repetitive administration of TVEC or other oncolytic viral immunotherapies mimicking unresolved infection can produce granulomatous inflammation confounding assessment of the degree of tumor response and need for additional TVEC therapy. Tumor biopsies are encouraged after 4 to 6 months of TVEC administration to differentiate melanoma from granulomatous inflammation. Patients with confirmed granulomatous dermatitis replace continued with remained in remission after treatment discontinuation. Inflammatory nodules typically regress spontaneously.

Squamous cell carcinoma arising from ovarian mature cystic teratoma and causing small bowel obstruction

Malignant transformation of mature cystic teratoma (MCT) is a rare phenomenon with incidence of approximately 1-3%. We report a 48-year-old woman who presented to the emergency room with symptoms of bowel obstruction. She underwent computed tomography scan for the evaluation of obstruction, which demonstrated diffuse ascites accompanying a cystic pelvic to lower abdominal mass which had invaded into the adjacent small bowel causing partial small bowel obstruction. Histologically, the mass demonstrated a MCT within which aroused a well-differentiated squamous cell carcinoma. Exploratory laparotomy was performed to confirm the diagnosis and debulking of the mass was performed.

Diphenhydramine as an alternative local anesthetic agent

Patients who present with a history of "allergy" to local anesthetics are common in clinical practice. Injectable 1% diphenhydramine is a safe, inexpensive, and effective local anesthetic for simple dermatological procedures in patients who report "caine" allergies. Utilizing this agent permits the dermatologist to operate at the time of the initial visit and schedule a referral to the allergist for definitive sensitivity testing at the patient's convenience.