No abstract

in 15/16 (93.7%) cases, including CK20, mostly 'dot-like' (12/13, 92.3%); CK (6/7, 85.7%), AE1/AE3 (3/3, 100%) and CK7 (1/6, 16.6%), along with neuroendocrine markers (16/16, 100%), including synaptophysin (11/13, 84.6%), chromogranin (12/15, 80%) and CD56 (4/4, 100%). Other positive IHC marker was CKIT/CD117 (3/3). Surgical resection was performed in 11/11 (100%) cases, with adjuvant chemotherapy offered in a single case. On follow-up (n=4 cases), two cases with large-sized tumours developed lymph node metastasis, including 1 who also developed pulmonary metastasis. Two patients were free-ofdisease (16 months, 21 months) and 2 were alive-with-disease. Conclusions: MCCs exhibit a wide histopathological spectrum, including co-existing Bowen's and rhabdomyoblastic de-differentiation. Careful analysis of key histopathological features and optimal IHC results with CK20, synaptophysin, chromogranin and CD56 are helpful in a timely diagnosis, as these are aggressive. MCCs also express CKIT.