A 70-year-old woman with two ill-defined lesions in the liver. Touch preparations and core liver biopsy shown. What are your differential diagnoses?

88-year-old with vulvar lesion. Diagnosis: Extramammary Paget's disease.

88-year-old with vulvar lesion. What's your diagnosis?

DDX of superficial pediatric small round blue cell tumors are sarcomas (Ewing family and fusion-associated); rhabdomyosarcoma; lymphomas/leukemias; neuroblastoma #dermpath #surgpath #blueskypath #blueskydermpath #blueskysurgpath #hemepath #blueskyhemepath #pathology #blueskypathology

A 3-month-old baby with an enlarging, abscess-like bump on the anterior fontanelle. Additional lumps appeared on ear and scalp, with hair loss and eroded skin. What are your differentials? #blueskypath #blueskyderm #pathsky #dermsky #dermpath #dermpathsky #pedipath #surgpath #pathology #dermatology

A 60-year-old man with skin lesions, DM and ESRD. Skin biopsy is from the leg. A cup-shaped ulcer with degenerated collagen and elastic fibers extruded through the ulcer. The findings are compatible with an acquired perforating collagenosis/dermatosis or umbilicated chronic prurigo nodularis.

A 60-year-old patient with skin lesions. Skin biopsy from the leg. What is your diagnosis?

Metastatic thyroid carcinoma to the scalp. #dermpath #surgicalpath #blueskypath #blueskypathology #blueskydermpath #immunohistochemistry #pathology

Excisional biopsy of 2.4 cm mass in left paramedian scalp. What's your diagnosis?