Spontaneous Tumor Lysis Syndrome in a Case of Hepatocellular Carcinoma with Sarcomatoid Differentiation.

Sarcomatoid hepatocellular carcinoma is a rare histologic variant of primary liver cancer comprising of malignant spindle cells and typical hepatocellular carcinoma (HCC). In terms of clinical presentation, they usually exhibit extensive tumor burden due to their larger size and a metastatic disease at the time of diagnosis as compared to conventional HCC. Tumor lysis syndrome is an oncological emergency, usually seen after cytotoxic chemotherapy in haematological malignancies. Here, we highlight a case of 76-year old male with no comorbidities, presenting with an excruciating backache and a paravertebral soft tissue mass and multiple osteolytic lesions, was clinically suspected to be a plasma cell neoplasm. On further evaluation, the patient was diagnosed of a sarcomatoid variant of hepatocellular carcinoma. This report showcases multiple rare findings by the presence of non-specific symptoms, non-cirrhotic liver, normal serum alpha protein levels and the occurrence of a spontaneous tumor lysis syndrome in a solid malignancy.

A nuanced exploration delving into malignant melanomas occurring in unexpected and less common anatomical locations.

Malignant melanoma originates from melanoma cells, which derive from the neuroectoderm of the ectodermal mucosa. The chameleonic presentation of malignant melanoma, its often asymptomatic nature, the rarity of the lesion, the grim prognosis, and the imperative for highly specialized treatment are critical factors that merit careful consideration. Herein, we report a compilation of five cases of malignant melanomas occurring at unusual anatomical locations, which were initially misdiagnosed, which on careful analysis with the use of immuno-histochemical stains were correctly diagnosed as malignant melanoma.

A Case of Medullary Carcinoma of Colon Morphologically Resembling Non-Hodgkin's Lymphoma.

Medullary carcinoma of the colon is an unusual and unique histologic subtype of colorectal cancer. It is strongly associated with microsatellite instability, most commonly loss of MLH1 indicative of deficient mismatch repair proteins. Diagnosis is challenging as they do not display the usual histological pattern. Immunohistochemical staining also shows unusual findings like negativity for CD20 and CDX2. Here, we explore an intriguing case of medullary carcinoma of colon which showed loss of MSH2 and MSH6 and a morphology reminiscent of Non-Hodgkin's lymphoma.

Synchronous Malignancies: Pathological Analysis of Three Patients, Each with Dual Malignancies.

Multiple primary malignancies are defined as two or more malignancies arising independently to each other in the same or different anatomical sites, while excluding the possibility of metastasis from the primary malignancy. Here, we present three cases, each with dual malignancies involving different anatomical locations.

Anaplastic (undifferentiated) carcinoma of pancreas, an uncommon variant: Diagnosed on endoscopic-guided fine needle aspiration.

Anaplastic carcinoma of pancreas (ACP) are rare pancreatic neoplasms. They are well known to be associated with more aggressive tumor behavior and less favorable prognosis than usual pancreatic ductal adenocarcinoma. Endoscopic-guided fine needle aspiration (EUS-FNA) is now a widely accepted modality in diagnosis of pancreatic lesions. However, only a few reports are available describing cytological features of anaplastic carcinoma. Here, we report two cases of ACP diagnosed on EUS-FNA.

Gastric Metastasis of Primary Neuroendocrine Tumor of Skin: Rare Tumor with Rare Presentation.

Merkel cell carcinoma (MCC) is a rare primary neuroendocrine tumor of the skin. It has an aggressive biological behavior and shows early local and distant metastasis. Diagnosis of MCC is a challenge and requires confirmation by immunohistochemistry (IHC). However, metastasis of MCC to the stomach is extremely uncommon and is rarely reported in the literature. We hereby describe a patient with gastric metastasis of MCC, who presented with black tarry stool and was finally diagnosed on the basis of clinical history, histology, and IHC.

Amelanotic Melanoma: A Great Masquerader.

Malignant melanoma is an aggressive, notorious tumor showing great variability in morphological and immunohistochemical expression, thus commonly leading to an erroneous diagnosis. Within the melanoma group, amelanotic melanoma, with its wide clinical presentations, lack of pigmentation, and varied histological appearances, has taken on a new persona as a master masquerader. Use of immunohistochemistry in the diagnosis of malignant tumors, including melanoma, is primordial and indispensable. However, the problem gets compounded in scenario of aberrant antigenic expression. The present case posed multiple diagnostic challenges in form of atypical clinical presentation, variant morphology, as well as aberrant antigenic expression. Here, we present the case of a 72-year-old male who, upon his initial presentation, was thought to be sarcomatoid anaplastic plasmacytoma, but 5 months later another biopsy from a different site revealed the actual diagnosis of amelanotic melanoma.

Transformation of ameloblastoma to ameloblastic carcinoma in a 10-year-old child.

Ameloblastic carcinoma (AC) is a rare odontogenic malignant epithelial neoplasm of maxillofacial skeleton with a distinct predisposition of the mandible. It can occur in a wide range of age groups, with a sex predilection in males. It can arise either as a de novo lesion or from preexisting ameloblastoma. AC has a high propensity for local recurrence as well as distant metastasis (chiefly lungs), thus requiring an aggressive surgical approach and a strict surveillance. Owing to the rarity of publications describing AC, little is known about this entity in pediatric patients. We report a case of transformation of ameloblastoma into AC in a 10-year-old child.

Cystic Pancreatic Neuroendocrine Tumor: A Diagnostic Dilemma.

Pancreatic neuroendocrine tumors are typically solid neoplasms but in rare instances may present as cystic lesions. Preoperative diagnosis of a cystic pancreatic lesion is challenging and requires a multidisciplinary and multimodal approach. We hereby describe an elderly female who came with complaints of abdominal lump. Radiologically, it appeared to be a pancreatic hydatid cyst located at the head of the pancreas, following which resection was done. Histopathological study of the lesion turned out to be a cystic pancreatic neuroendocrine tumor. Thus, we present this unique case due to its rarity and diagnostic challenge.

Hearts don't lie: Cardiac tuberculosis diagnosed on fine-needle aspiration cytology.

Cardiac involvement in tuberculosis is relatively rare when compared to other organs and often involves the pericardium leading to constrictive pericarditis. Myocardial tuberculoma is exceedingly rare and only seldom cases have yet been reported. Our report is of a case diagnosed on fine-needle aspiration cytology.

Twin Fetus-in-Fetu: The Story of an Encaged Twin.

Background: Fetus-in-fetu (FIF) features a monozygotic, diamniotic, parasitic twin enclosed within its host twin. Case report: An 11-month baby girl presented with an antenatal diagnosis of a retroperitoneal mass. Radiological findings suggested it to be a teratoma. The mass was excised in-toto, histological findings were consistent with fetus-in-fetu. Conclusions: FIF may not have identifiable vertebral bodies and limbs upon imaging. Organized organ systems help differentiate this from a teratoma.

Liver abscesses caused by visceral larva migrans: Aimless wanderer separated from the host.

Visceral larva migrans (VLM) is a systemic zoonotic parasitic disease caused by migration of the second stage larva through viscera of humans. Despite being a foremost public health problem in low- and middle-income countries (LMICs) such as India, larva migrans remains an untended zoonosis. Here, we report two cases of VLM who presented with fever and abdominal pain for a prolonged duration. On further investigation, marked peripheral eosinophilia with multiple confluent necrotizing eosinophilic granulomas were identified on histopathological examination of the liver.

Concomitant Langerhans and Interdigitating Reticulum Cell Hyperplasia in a Reactive Lymph Node of an Infant with Omenn Syndrome: A Diagnostic Pitfall for Langerhans Cell Histiocytosis.

Omenn syndrome, a rare form of combined immunodeficiency in infants, presenting with recurrent infections, erythroderma, lymphadenopathy, hepatosplenomegaly, eosinophilia, and increased serum IgE levels. It is a fatal condition unless treated by hematopoietic stem cell transplant. Hence, an early diagnosis and a prompt treatment can lead to better outcome in these unfortunate babies afflicted with Omenn syndrome. Here, we present an 8-week-old infant with typical features of Omenn syndrome, both clinically as well as on laboratory analysis, but surprising immunohistochemical findings on lymph node biopsy.

Acantholytic Squamous Cell Carcinoma: a Diagnostic Pitfall on Cytology.

Acantholytic squamous cell carcinoma is an infrequent subtype of squamous cell carcinoma. This tumour variant being rare in itself has been rarely described at the penile location, thus leading to a limitation on information of pathological and immunohistochemical findings and prognosis. Clinical observations indicate an aggressive biologic behaviour. The cytological features on fine-needle aspiration cytology samples have rarely been described in literature. It is imperative for pathologists to be aware of the cytological features so as to allow the distinction of this variant from conventional squamous carcinoma. Here, we explore an intriguing case of a metastatic tumour to inguinal lymph node with the primary lesion at the penis which constituted a diagnostic challenge on cytological examination.

Primary fallopian tube endometroid carcinoma: A rare case report.

ABSTRACT: Primary fallopian tube carcinoma is an extremely rare tumor accounting for only 0.14-1.8% of genital tract cancers. A 47-year-old female presented with post-menopausal bleeding and heaviness in the lower abdomen. Imaging revealed the right adnexal mass, suggestive of neoplastic origin. She was prepared for surgery. Per-operatively, there was a solid irregular mass, firm to hard in consistency, around 8 × 5 cm involving the whole of the right fallopian tube, and the right ovary appeared normal. Histopathological examination of the specimen showed endometroid adenocarcinoma of the right fallopian tube. Endometroid carcinoma is important to recognize because it carries the best prognosis of all the fallopian tube cancers. The patient underwent surgery, followed by adjuvant chemotherapy, and was doing well in follow-up.

Squamous cell carcinoma arising from keratinizing desquamative squamous metaplasia of renal pelvis and double paraneoplastic syndrome: Association of two rare entities.

Keratinizing desquamative squamous metaplasia (KDSM) of the upper urinary tract is a rare entity. The present case is of a 45-year-old female patient with an 8-month history of abdominal lump, recurrent right lumbar pain, intermittent fever, and oliguria. Computed tomography kidney, ureter, and bladder revealed a grossly enlarged right kidney along with heterogeneously enhancing soft tissue density mass and internal septations. A differential diagnosis of renal cell carcinoma, urothelial carcinoma, tuberculosis, and pyonephrosis of the kidney was considered as per the clinical and radiological presentation. Intraoperatively, thick fluid was seen in the kidney and its pedicle was seen adhered to duodenum. Partial nephrectomy was done and on microscopic examination squamous cell carcinoma (SCC) was seen arising in the setting of KDSM. Postoperatively, the patient showed an exponential rise of total leukocyte count (100/153 × 103/µl) and serum calcium levels (10.1/17.2/20.4 mg/dl); eventually started deteriorating and later succumbed to illness. We report this rare association of SCC of the renal pelvis arising in KDSM along with the double paraneoplastic syndrome.

Glomus Tumor of Scrotum and Stomach: Usual Tumor at Unusual Locations.

Glomus tumor is a rare benign neoplasm, accounting for less than 2% of all the soft tissue tumors. Although they can develop in any part of the body, they commonly do so in upper extremities, most commonly in fingers. Here, we report two cases of glomus tumor at rare locations, in order to increase the awareness of this tumor entity in unusual sites. We also highlight the clinicopathological features and differential diagnoses of this tumor.

Common Variable Immunodeficiency Enteropathy and Its Unpredictable Biopsy Findings: Not Everything Is Black and White.

Common variable immunodeficiency syndrome (CVID) is a diverse entity characterized by hypogammaglobinemia and a propensity for recurrent infections. Involvement of the gastrointestinal tract has a variable manifestation ranging from asymptomatic involvement to florid signs and symptoms. Due to these incongruous findings, multiple concurrent biopsies are to be done for tissue diagnosis. Here, we present two cases diagnosed with CVID on the basis of clinical findings, lab investigations, and morphological features on biopsy.