CASE OF THE MONTH AUGUST-2015 DR. GURUDUTT GUPTA HEAD HISTOPATHOLOGY

Transcription

1 CASE OF THE MONTH AUGUST-2015 DR. GURUDUTT GUPTA HEAD HISTOPATHOLOGY

2 CASE HISTORY 52Y MALE RIGHT RADICAL NEPHERECTOMY Case of right renal mass with IVC thrombus. History of surgery and RT for right occipital hemangiomatous meningioma outside in 2005 and with recurrence of meningioma in 2010 Laparoscopic cholecystectomy in 2013 Presented with breathlessness and pain in lower limbs for one month

3 RADIOLOGY

4 Radiology A well defined, exophytic, heterogeneously enhancing lobulated mass is seen arising from medial aspect of upper pole of Right kidney. The mass is not extending in right renal pelvis. Upper lobe branches of right renal artery is encased by the mass, however main right renal artery and vein appear normal. The lesion is not extending beyond fascia of Gerota. Non enhancing intraluminal filling defect is seen in IVC extending from its infrahepatic portion superiorly and inferiorly upto the bilateral common iliac,bilateral external iliac veins and Lt internal ilaic vein s/o bland thrombus. Few of the thoracic cuts taken show non enhancing intraluminal filling defect in right pulmonary artery extending into the posterior segmental branches and also in posterior segmental branches of left pulmonary artery s/o thrombus. Cm/subcm nodes are seen in preaortic, paraaortic and aortocaval regions. IMPRESSION: Right renal mass likely RCC with extensions, nonenhancing IVC, bilateral common/external iliac vein and pulmonary artery thrombus, cm/subcm sized retroperitoneal lymph nodes and other findings as described.

5 GROSS Nephrectomy specimen 20x10.5x6 cm Kidney 11x6x5.5 cm Tumor 5.3x5.1x4.5 cm - Upper pole Solid grey white homogeneous well circumscribed Limited to kidney Smaller lesion measuring 0.6 cm in diameter seen at lower pole No hilar or renal vein invasion seen

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7 DIAGNOSIS?

8 Renal cell carcinoma? Mesenchymal tumor- Benign/Malignant

9 H&E Tumor composed of oval to spindle cell arranged in short interlacing fascicles. Cells have vesicular chromatin with moderate amphophilic cytoplasm Mild to moderate pleomorphism is noted Mitosis is 5-6/10 hpf Background shows hyalinized collagen No necrosis seen The mass is well circumscribed, while smaller lesion is infiltrating into renal parenchyma No lymph vascular invasion or large vessels invasion seen

10 Well circumscribed tumor, with compressed renal tissue at the periphery

11 Spindle to oval cells, arranged in short interlacing vessels. Hylanized vessels noted

12 Few scattered tumor giant cells and collagenization

13 Tumor giant cells

14 DIAGNOSIS?

15 Spindle cell sarcoma Sarcomatoid renal cell carcinoma Angiomyolipoma SFT Monophasic synovial sarcoma

16 IHC h-caldesmon

17 IHC HHF-35

18 IHC - VIMENTIN

19 IHC summary Immunopositive for vimentin, H - Caldesmon and HHF-35 Immunonegative for Pan-CK(AE1/AE3), PAX8, EMA, S-100, CD34, SMA, Desmin, Melan-A, SMMH, TLE-1, CD117 and Beta - Catenin

20 Diagnosis Spindle cell sarcoma- FNCLCC grade 1 Favoring Leiomyosarcoma Rule out synovial sarcoma by t(x;18) translocation study

21 Discussion Mesenchymal Tumors Occurring Mainly in Adults Leiomyosarcoma (including renal vein) Angiosarcoma Rhabdomyosarcoma Malignant fibrous histiocytoma Haemangiopericytoma Osteosarcoma Angiomyolipoma Epithelioid angiomyolipoma Leiomyoma Haemangioma Lymphangioma Juxtaglomerular cell tumour Renomedullary interstitial cell tumour Schwannoma Solitary fibrous tumour

22 Cont In our case the differential considered were : 1. Leiomyosarcoma 2. Sarcomatoid RCC 3. Monophasic synovial sarcoma 4. Angiomyolipoma 5. Solitary fibrous tumor

23 Cont The Sarcomatoid RCC was ruled out by absence of high grade morphological features and immunonegativity for PAX8, CK and EMA The Angiomyolipoma was ruled out due to lack of radiological features, absence of thick-walled blood vessels, fat, myomatous elements, and branching lymphatic spaces. Melan-A, SMA, Desmin were negative Solitary fibrous tumor was considered but presence of two foci with infiltration of renal parenchyma, mitosis and CD34 immunegativity ruled out benign SFT.

24 Cont The Leiomyosarcoma and mono-phasic synovial sarcoma were close differentials with IHC and Morphological features favoring Leiomyosarcoma The adult Mesenchymal tumors of kidney are uncommon, with Angiomyolipoma being most common benign tumor and Leiomyosarcoma being most common malignant tumor(45-50% of cases) Most of the reported cases are available as case reports and small studies. The prognosis of Leiomyosarcoma is poor. With 85% succumb within two years of diagnosis with Recurrence and Metastasis Some reports predict a better prognosis for Grade 1 tumors that are confined to Kidney with R0 resection Surgery is the modality of choice with best results in tumors measuring less than 5 cm and are completely resected

25 Cont Diagnosis in our case is more of exclusion with h-caldesmon positivity H-Caldesmon is considered most sensitive marker for smooth muscle differentiation It may also be positive in cases of GIST X;18 translocation studies should be done in spindle cell tumors of the kidney to exclude synovial sarcoma