Recommendations of a group of experts for the pathological assessment of tumour regression of liver metastases of colorectal cancer and damage of non-tumour liver tissue after neoadjuvant therapy.

Colorectal cancer (CRC) incidence has increased during the past decades in Spain, being the first malignant tumour in incidence. Observed mortality for CRC is mainly due to liver and lung metastases. The only curative treatment is surgery; new surgical techniques and neoadjuvant treatments have increased the number of surgery candidate patients. Patients should be managed with a multidisciplinary approach that includes imaging techniques, chemotherapy, surgery and pathological assessment. As an answer to this approach, a group of pathology experts interested on CRC liver metastases aimed to review the diagnosis and prognosis of liver mestastases and developed practical recommendations for its assessment. The expert group revised the current literature and prepared questions to be discussed based on available evidence and on their clinical practise. As a result, recommendations for the assessment of tumour regression of liver metastases are proposed, which could be implemented in oncology centres allowing assessment standardisation for these patients. Prospective multi-center studies to evaluate these recommendations validity will further contribute to improve the standard care of CRC liver metastases patients.

Estudio del anticuerpo DOG1 en el diagnóstico de tumores del estroma gastrointestinal – GIST / The role of the DOG1 antibody in the diagnosis of gastrointestinal stromal tumours – GIST

Los tumores del estroma gastrointestinal (GIST)poseen mutaciones en los genes del receptor de la tirosínquinasa (RTKs) KIT y PDGFRA. La posibilidad debloquear esta actividad ha significado una nueva esperanzaterapéutica. El diagnóstico de GIST recae en laexpresión inmunohistoquímica del c-KIT, pero un 4-15%son c-KIT negativos (aún en presencia de mutación), ysin embargo estos pacientes podrían beneficiarse deltratamiento con inhibidores tirosín quinasa (TKIs).El DOG1 es un nuevo anticuerpo cuya sensibilidady especificidad parece ser superior o igual a la del c-KIT.El objetivo de este trabajo es evaluar la sensibilidad(Se) y especificidad (Sp) de DOG1 en GIST de tipo usual(c-KIT positivos), de tipo inusual (c-KIT negativos) yfrente a otros tumores fusocelulares mesenquimales, ycomparar la validez diagnóstica del DOG1 frente al c-KIT.Estudiamos 40 GIST, 39 c-KIT positivos y un c-KITnegativo. Se realizó un panel inmunohistoquímico conlos anticuerpos: c-KIT, CD34, actina músculo liso, DOG1y S100, en los GIST como en siete tumores fusocelulares.La Se y Sp de GIST para DOG1 fue del 100 y 97,5%para c-KIT. La inmunoreactividad para DOG1 en todoslos tumores fusocelulares fue negativa. La validez diagnósticade DOG1 y C-KIT fue similar a la hora de detectarGIST y no GIST.DOG1 es un marcador específico y sensible para eldiagnóstico y diagnóstico diferencial de GISTs (es capazde detectar algunos GIST sin mutación en RTK).El DOG1 debería de formar parte del panel inmunohistoquímicopara el diagnóstico de GIST(AU)

Gatrointestinal stromal tumours (GIST) harbouroncogenic mutations in tyrosin kynases receptors(RTKs) including KIT and PDGFRA. The inhibition ofthis activity has been regarded as the primary target forthe treatment of these patients. Diagnosis of GIST relieson c-KIT inmunoreactivity; however there is a 4-15% ofGISTs that are C-KIT negative which may lead to underdiagnosisof GISTs and possible withholding of therapy.The novel gene DOG1 has been found overexpressedin GISTs and has potential as a diagnostic markerfor GISTs showing even more sensitivity (Se) and specificity(Sp) than c-KIT for the diagnosis of these tumors.In this study we compared the (Se) and (Sp) of DOG1 intypical and atypical GISTs (c-KIT positive or negative)with c-KIT and other mesenchymal neoplasms in thedifferential diagnosis of GISTsWe examined 40 GIST (39 showed inmunoreactivityfor c-KIT and one was c-KIT negative) and anotherseven fusiform tumors. An inmunohistochemical panelwas performed with c-KIT, CD34, smooth muscle actin,DOG1 and S100 antibodies on both types of neoplasms.The overall Se and Sp of DOG1 and KIT in GISTswere nearly identical: 100 and 97,5%. Negativity forDOG1 was observed in all fusiform mesenchymal neoplasms.DOG1 is highly expressed in GIST and its expressionseems quite specific for these tumours when thedifferential diagnosis includes another mesenchymalneoplasms.DOG1 should be added to the diagnostic panel evaluatingGISTs(AU)

Cutaneous nodes in a patient with advanced papillary carcinoma of the thyroid

Cutaneous metastasis from thyroid carcinoma is infrequent. Leukemia as a second malignancy after treatment of thyroid cancer is also rare. We present a patient with a relapsed thyroid carcinoma treated with thyroid ablation with I 131 and loco-regional radiotherapy, who consulted by global worsening, weight lost, and multiple cutaneous nodes. Our patient is unusual in that she showed multisystem involvement at the time of hospital admission, and the specific skin lesions were the first sign of her acute monocytic leukemia (AU)

[Metanephric stromal tumor: report of two cases and bibliographic review]. / Tumor del estroma metanéfrico: presentación de dos casos en adultos y revisión de la literatura.

OBJECTIVE: Metanephric Stromal Tumors (MST) are pediatric renal neoplasms not very common in adults. This study revises its classification, incidence and evolution and also some specific characteristics of the cases diagnosed in adults. METHODS: We present two cases of MST diagnosed in adults of 72 and 77 years old respectively. Abdominal pain due to a more than 4 Kg. mass was the initial presentation in both cases. The tumors were completely resected. Four and ten years after excision patients are alive without disease. RESULTS: Characteristic histologic features include a proliferation of fusocellular cells with alternating cellularity that imparts a nodular appearance and onion-skin cuffing around entrapped renal tubules or vascular structures. No mitoses or atypia was found but extensive necrosis and fibrosis were present. A majority of stromal cells were vimentine and CD-34 positive. Stains for CK and EMA highlighted entrapped native tubules. Both cases were previously classified as mesoblastic nephromas. According to the 2002 ONS classification of tumours of the urinary system, they have been revised and re-classified as MST CONCLUSION: MST are pediatric benign tumors exceptionally diagnosed in adults. Metanephric stromal tumors are divided into 3 categories based on the presence of epithelial cells, stroma and epithelial cells plus stromal. Complete excision is the treatment of choice and the prognosis is excellent.

[Florid glandular cystitis of the intestinal type with mucin extravasation: a lesion simulating a tumor]. / Cistitis glandular florida de tipo intestinal con extravasación de mucina: una lesión que simula un tumor.

A wide spectrum of glandular epitheliales metaplastic changes may be seen in the bladder. Extensive replacement of the urotelium with an epithelium resembling intestinal mucosa is recognised as a premalignant condition. However, the natural history of intestinal metaplasia of the urinary bladder and long-term outcome are unknown. We report a case of glandular cystitis with intestinal metaplasia in a young patient. Cystoscopy revealed a tumour well circumscribed measuring 4 cm on the trigone. Microscopic examination showed numerous glands lined by intestinal type epithelium without atipia, conforming to the appearance of the intestinal variant of cystitis glandularis. This case had prominent foci of basophilic mucin in the stroma. Rounded aggregates of mucin were occasionally surrounded by compressed connective tissue cells, simulating mucinous cyst. This case illustrates the extent to which cystitis glandularis may mimic a neoplasm on gross evaluation and the propensity of mucin extravasation to cause diagnostic difficulty, a finding documented only rarely previously, and we discuss its biologic significance.

Cistitis glandular florida de tipo intestinal con extravasación de mucina: una lesión que simula un tumor / Florid cystitis glandularis of intestinal type with mucin extravasation: a mimic of tumour

En la vejiga se pueden observar una gran variedad de lesiones o cambios metaplásicos epiteliales. La sustitución extensa del urotelio por epitelio similar a la mucosa intestinal se ha considerado como una lesión premaligna. Sin embargo, la historia natural de la metaplasia intestinal y su comportamiento a largo plazo es desconocida. Presentamos un caso de cistitis glandular de tipo intestinal vejiga en un paciente joven. En la cistoscopia se observó un tumor bien circunscrito de 4 cm localizado en trígono. Histológicamente la lesión mostraba numerosas glándulas revestidas por epitelio de tipo intestinal sin atipia citológica correspondiente a la variedad intestinal de la cistitis glandular. Destacaba en este caso el depósito de un material basófilo en el estroma correspondiente a mucina. Se podía ver acúmulos de este material rodeados y comprimidos por tejido conectivo, simulando quistes mucosos. Este caso demuestra que en el estudio cistoscópico la cistitis glandular puede simular un tumor cuando la lesión es extensa. Y que la extravasación de mucina puede causar un problema de diagnóstico diferencial con un tumor maligno, un hallazgo que ha sido raramente documentado previamente. Se discute además el significado biológico de ese tipo de lesión (AU)

[Spermatic cord liposarcoma: differential diagnostic criteria and treatment]. / Liposarcoma de cordón espermático: criterios de diagnóstico diferencial y tratamiento.

OBJECTIVE: To report a case of liposarcoma of the spermatic cord in a young male, with special reference to the difficulties encountered in making the clinical and histopathological differential diagnosis. METHODS/RESULTS: A 43-year-old patient underwent surgery for a tumor (8 x 7 cms) in the left spermatic cord. Pathological analysis demonstrated a well-differentiated liposarcoma with myxoid areas. Radical orchidectomy was performed. The patient is well, with no tumor recurrence or metastasis. RESULTS/CONCLUSIONS: Paratesticular liposarcoma is rare. It is therefore difficult to establish the guidelines for treatment, prognosis and differential diagnosis. Similarly, difficulty is encountered when making the preoperative diagnosis, although US and CT can be useful. As in liposarcomas localized to other sites, the histological type and grade of the lesion are useful for the prognosis. Radical inguinal orchidectomy is the treatment of choice.

[Conservative treatment of microcytic carcinoma of the bladder; report of a new case]. / Tratamiento conservador en carcinoma microcítico de vejiga; aportación de un nuevo caso.

OBJECTIVE: To report an additional case of small cell carcinoma treated conservatively. METHODS: Herein we describe a case of small cell carcinoma of the bladder that had been treated conservatively because of the age of the patient. The specific characteristics of the case are described and the clinical and pathological aspects of the disease are briefly reviewed. RESULTS/CONCLUSION: Although treatment of this disease is primarily by cystectomy followed by chemo and radiotherapy, organ-sparing neoadjuvant chemo and radiotherapy as an alternative to surgery could be attempted to obtain complete remission in selected patients.

[Cystadenoma of the pancreas: presentation of 3 new cases]. / Cistoadenoma del páncreas: aportación de tres nuevos casos.

The authors contribute three new cases of pancreatic cystadenoma, two of the mucinous variety and one microcystic-serous, to the series of cases that have appeared in the recent literature. Emphasis is placed on the importance of a correct surgical strategy in the approach to the problem of cystic pancreatic tumors. The importance of microscopic study of the varieties of cystadenoma and their possible prognostic implications are considered.