1/4/22 C.  SKIN OF BACK, LOWER, SHAVE BIOPSY: -  Melanocytic nevus,compound type, with unusual architectural features and severe cytologic atypia. -  Lesion extends to peripheral edge and base of biopsy specimen.   Diagnosis Comment  In specimen (C), the findings are those of a compound nevus with severe atypia. The junctional component predominates and shows concerning features including the degree of individual cell growth with scattered cells extending above the basal zone and associated cytologic atypia, In foci, the features approach those of melanoma. However, despite deeper levels and immunohistochemical stains definitive criteria for melanoma, including well-developed confluent growth and upward migration, are not noted. The nevus extends to the biopsy edge and base. Representative slides of this case were reviewed at the intradepartmental consultation conference.     Attestation  By the signature below, the attending physician certifies that they have 1) personally conducted a gross and/or microscopic examination of the described specimen(s), and/or personally interpreted the results of laboratory testing of the described specimen(s), and 2) personally rendered or confirmed the above diagnosis.   Microscopic Description  (A, B) Irregularly shaped islands of atypical basal cells infiltrate the dermis.  The basal cells have scant cytoplasm and round dark nuclei.  Mitotic figures and apoptotic bodies are evident.  The nuclei at the periphery of the islands have a palisaded arrangement.  The islands are associated with a fibromyxoid stroma and there is cleft formation between some of the islands and stroma.     (C) The epidermis is hyperplastic with elongate and anastomosing rete ridges.  There is a compound proliferation of melanocytes within the epidermis that consists of nests and individual cells.  The nests predominate but vary to a moderate degree in size, shape, and spacing.  The nests are located between and on the sides of the rete ridges, in addition to at the tips of the ridges.  Nests bridge rete ridges.  Focally, individual melanocytes are prominent and show uneven spacing with crowding along the dermal-epidermal junction and scattered cells extending above th basal zone. However, neither well-developed confluent growth or well-developed upward migration are noted.  The melanocytes are enlarged and have ill-defined cytoplasm containing melanin pigment.  The nuclei show a severe degree of size and shape variation with occasional large, irregular forms. Nests and strands or melanocytes are present within the dermis and show maturation with descent. SOX-10 ALK PHOS (SP267, Cell Marque) does not show evidence of well-developed confluent growth and upper migration.  Additional sections have been reviewed.   NOTE:  "One or more of the reagents used in immunoperoxidase testing in this case may not have been cleared or approved by the U.S. Food and Drug Administration (FDA).  The FDA has determined that such clearance or approval is not necessary.  These tests are used for clinical purposes.  They should not be regarded as investigational or for research.  These reagents' performance characteristics have been determined by the referring laboratory.  The positive and negative controls worked appropriately. If immunoperoxidase staining has been performed on alcohol fixed cytology specimens, which has not been fully validated, the assays should be interpreted with caution and correlated with clinical data.  This laboratory is certified as qualified to perform high complexity clinical laboratory testing.?   Clinical History  A. Central forehead, pink pearly papule; R/O BCC vs other; B. Central chest, pink plaque; R/O BCC vs other; C. Lower back, brown irregularly pigmented macule; R/O MM vs atypical nevus; clinical diagnosis code: D48.5   Gross Description  A. Received in formalin labelled with proper patient identification (initials P, D) and "central forehead" is a 0.4 x 0.3 x 0.1 cm ovoid shave of tan-gray skin.  The margin is inked.  The specimen is submitted intact in A1.   B. Received in formalin labelled with proper patient identification (initials P, D) and "central chest" is a 0.5 x 0.4 x 0.1 cm irregular shave of tan-gray skin.  The margin is inked.  The specimen is submitted intact in B1.   C. Received in formalin labelled with proper patient identification (initials P, D) and "lower back" is a 1.2 x 0.8 x 0.1 cm irregular shave of friable tan-gray to dark brown skin.  The margin is inked.  The specimen is trisected and entirely submitted in C1.   1/4/2022 16:18