SlideShare a Scribd company logo
1 of 17
Diagnostic approaches In CUP
Neck(Carcinoma of Unknown
Primary)
DR.E.KAUSHIK KUMAR
DEPARTMENT OF GENERAL SURGERY
STANLEY MEDICAL COLLEGE
• குறள் 71:
அன்பிற்கும் உண்டைோ அடைக்குந்தோழ்
ஆர்வலர்
புன்கண ீர் பூசல் தரும். :
அன்பிற்கும் கூைப் பிறர் அறியோமல்
தன்டை மூடி டவக்கும் கதவு உண்டைோ?
இல்டல. தம்மோல் அன்பு
சசய்யப்பட்ைவரின் துன்பத்டதக்
கோணும்டபோது வடியும் கண்ண ீடே அன்பு
உள்ளத்டதக் கோட்டிவிடும்.
AIM
• Clarifying the histology of the nodal
metastases
• Detecting the primary.
History
• Family and Personal history, including history of previous
malignancy both in the head and neck, and elsewhere
• History of previous radiation
• History of a previous facial or cervical skin lesion that has
disappeared
• History of any upper aero-digestive tract related
symptoms (sore throat, otalgia, hoarseness, dysphagia,
hearing loss or epistaxis)
• Previous operations (breast, abdomen, chest, etc.).
Clinical Evaluation
• Scrupulous physical and fiber-optic evaluation of the
head and neck district including palpation of the oral
cavity, oropharynx, and base of the tongue, and search
for scars in the head and neck indicating previous
surgery.
• Examination of the neck, which includes site, size,
mobility, and relationship of the node(s) to the adjacent
structures.
• Complete physical examination for abnormalities
elsewhere: breast, axilla, groins, testicles, abdomen.
Investigations
• FNAC
• Imaging
• Endoscopy
• Molecular assays
• Examination under General Anaesthesia
FNAC
• Recommended if the above evaluation does not
detect any primary.
• Repetitive non-diagnostic FNACs- an indication for an
open biopsy, intra-operative histologic examination
and possible neck dissection
• Performed by experienced specialists
• Allow detection of the primary in more than 50% of
patients
IMAGING
• Head and Neck- CT, MRI
• CECT Thorax
– Trachea
– Oesophagus
– Lungs
• CECT Abdomen
– Liver
– Ovary
– Testes
– Prostate
PET-CT
• Overall staging accuracy -69-78%
• Positive predictive value -56-83%
• Negative predictive value-75-86%
• Sensitivity-63-100%
• Specificity -90– 94%
• With negative routine clinical examination, CT, and
MRI, PET scan allows detection of primary tumours
in 5-43% of patients.
• Higher rates of primary tumour detection-non-head
and-neck CUP or histologies other than SCC
• The resolution of the PET scan limited to 5 mm
• Tumours of the supraglottic region and Waldeyer’ s
tonsillar ring-most difficult to be diagnosed with
FDG-PET
– low tumour volume in small, superficial lesions
– the presence of normal lymphoid tissues
– accumulation of FDG secreted by salivary glands to saliva
pools in the valleculae and pyriform sinuses
– Improved detection may probably be achieved with a 12-h
pre-study fast,
• Ideally, biopsies should be performed after PET scan
– Sampling of the areas suspected in PET
– Avoids false positive PET-scans at biopsy site.
• Exclusion of other metastases
• Post-radiotherapy neck evaluation
• Subsequent monitoring
Endoscopy
• Tracheo-broncoscopy
• Oesophago-Gastroscopy
• Colonscopy
MOLECULAR ASSAYS
• Recently proposed to differentiate the potential primary site.
• Detection of the Epstein-Barr virus (EBV) with the use of in situ
hybridization in metastatic lymph nodes may suggest
nasopharyngeal tumour
• Human Papilloma virus (HPV) detected by polymerase chain
reaction may indicate oropharyngeal cancer
• Microsatellite mutation analysis of metastatic nodal tissue and
samples of normal pharyngeal mucosa
• In CUP the primary acquires a metastatic phenotype soon after
transformation and remains small, either by inborn errors leading
to involution of the primary, or due to extremely slow growth rate
• Inhibiting the growth of the primary by metastases
Examination under general
anaesthesia
• When the primary is not dectected, an evaluation
under general anaesthesia is mandatory.
• Biopsies are taken from all sites suspicious at the
clinical and imaging evaluation, and blindly from
the sites of possible origin of the primary
– base of tongue
– tonsil or tonsillar fossa
– pyriform sinus
– nasopharynx.
• Another option is open biopsy
• Increased risk of distant metastases following
this procedure has been suggested
• Detection rate
– CT scan -15-20%
– Panendoscopy with biopsies -up to 65%
• The most common sites of primary (82%)
– Tonsil
– Base of tongue
THANK YOU

More Related Content

What's hot

What's hot (20)

Cancer of unknown primay ao study day oct 2013
Cancer of unknown primay ao study day oct 2013Cancer of unknown primay ao study day oct 2013
Cancer of unknown primay ao study day oct 2013
 
Management of sinonasal tract tumors 27082018
Management of sinonasal tract tumors 27082018Management of sinonasal tract tumors 27082018
Management of sinonasal tract tumors 27082018
 
Metastatic Neck node of Unknown Primary
Metastatic Neck node of Unknown PrimaryMetastatic Neck node of Unknown Primary
Metastatic Neck node of Unknown Primary
 
Neck node management of unknown primary
Neck node management of unknown primaryNeck node management of unknown primary
Neck node management of unknown primary
 
Metastasis of Neck Node with Unknown Primary
Metastasis of Neck Node with Unknown Primary Metastasis of Neck Node with Unknown Primary
Metastasis of Neck Node with Unknown Primary
 
Management of neck metastasis (1)
Management of neck metastasis (1)Management of neck metastasis (1)
Management of neck metastasis (1)
 
Ca esophagus 12th
Ca esophagus 12thCa esophagus 12th
Ca esophagus 12th
 
3 field lymphnode dissection of esophagus
3 field lymphnode  dissection of esophagus3 field lymphnode  dissection of esophagus
3 field lymphnode dissection of esophagus
 
Carcinoma stomach 2 dr.kiran
Carcinoma stomach  2 dr.kiranCarcinoma stomach  2 dr.kiran
Carcinoma stomach 2 dr.kiran
 
Carcinoma rectum
Carcinoma   rectumCarcinoma   rectum
Carcinoma rectum
 
Management of the axilla after neoadjuvant chemotherapy
Management of the axilla after neoadjuvant chemotherapyManagement of the axilla after neoadjuvant chemotherapy
Management of the axilla after neoadjuvant chemotherapy
 
Colo-rectal Carcinoma at a glance !!!
Colo-rectal Carcinoma at  a glance !!!Colo-rectal Carcinoma at  a glance !!!
Colo-rectal Carcinoma at a glance !!!
 
Pancreatic tumours
Pancreatic tumours Pancreatic tumours
Pancreatic tumours
 
NMIBC Urianary Bladder Malignancy
NMIBC Urianary Bladder MalignancyNMIBC Urianary Bladder Malignancy
NMIBC Urianary Bladder Malignancy
 
Retro peritoneal sarcoma
Retro peritoneal sarcomaRetro peritoneal sarcoma
Retro peritoneal sarcoma
 
Role of MSCT in evaluation of pancreatic tumors and its resectability with pr...
Role of MSCT in evaluation of pancreatic tumors and its resectability with pr...Role of MSCT in evaluation of pancreatic tumors and its resectability with pr...
Role of MSCT in evaluation of pancreatic tumors and its resectability with pr...
 
Neoadjuvant therapy in colorectal carcinoma
Neoadjuvant therapy in colorectal carcinomaNeoadjuvant therapy in colorectal carcinoma
Neoadjuvant therapy in colorectal carcinoma
 
Carcinoma esophagus
Carcinoma esophagusCarcinoma esophagus
Carcinoma esophagus
 
Carcinoma rectum (Rectal Cancer)
Carcinoma rectum (Rectal Cancer)Carcinoma rectum (Rectal Cancer)
Carcinoma rectum (Rectal Cancer)
 
Staging and Diagnostic approach of rectal cancer
 Staging and Diagnostic approach  of rectal cancer Staging and Diagnostic approach  of rectal cancer
Staging and Diagnostic approach of rectal cancer
 

Similar to Diagnostic approaches in cup(carcinoma of unknown primary

Prostate presentation.Ca prostate etiology staging
Prostate presentation.Ca prostate etiology stagingProstate presentation.Ca prostate etiology staging
Prostate presentation.Ca prostate etiology staging
OSBORNMIKE
 

Similar to Diagnostic approaches in cup(carcinoma of unknown primary (20)

Abnormal Cervical Smear Presentation .pptx
Abnormal Cervical Smear Presentation .pptxAbnormal Cervical Smear Presentation .pptx
Abnormal Cervical Smear Presentation .pptx
 
Cervical cancer ppt
Cervical cancer pptCervical cancer ppt
Cervical cancer ppt
 
Cin&cancer cervix undergraduate
Cin&cancer cervix undergraduateCin&cancer cervix undergraduate
Cin&cancer cervix undergraduate
 
Gyne procedure
Gyne procedure Gyne procedure
Gyne procedure
 
CA Prostate
CA ProstateCA Prostate
CA Prostate
 
Prostate presentation.Ca prostate etiology staging
Prostate presentation.Ca prostate etiology stagingProstate presentation.Ca prostate etiology staging
Prostate presentation.Ca prostate etiology staging
 
Dilemma
DilemmaDilemma
Dilemma
 
Rectal Cancer
Rectal CancerRectal Cancer
Rectal Cancer
 
Prostate caner
Prostate canerProstate caner
Prostate caner
 
Investigations in gynaecology
Investigations in gynaecologyInvestigations in gynaecology
Investigations in gynaecology
 
Prostate Biopsy.pptx
Prostate Biopsy.pptxProstate Biopsy.pptx
Prostate Biopsy.pptx
 
Prenatal diagnosis
Prenatal diagnosisPrenatal diagnosis
Prenatal diagnosis
 
Breast lump
Breast lumpBreast lump
Breast lump
 
CRANIAL ULTRASONOGRAPHY IN NEWBORN
CRANIAL ULTRASONOGRAPHY IN NEWBORNCRANIAL ULTRASONOGRAPHY IN NEWBORN
CRANIAL ULTRASONOGRAPHY IN NEWBORN
 
pca mets.pptx
pca mets.pptxpca mets.pptx
pca mets.pptx
 
Cystic neoplasm of pancrease dr mnr
Cystic neoplasm of pancrease dr mnrCystic neoplasm of pancrease dr mnr
Cystic neoplasm of pancrease dr mnr
 
Prostate Biopsy--New Emerging Trends, Dr. Muhammad Bin Zulfiqar
Prostate Biopsy--New Emerging Trends, Dr. Muhammad Bin Zulfiqar Prostate Biopsy--New Emerging Trends, Dr. Muhammad Bin Zulfiqar
Prostate Biopsy--New Emerging Trends, Dr. Muhammad Bin Zulfiqar
 
METASTATIC NECK DISEASE FOR ENT & HNS.pptx
METASTATIC NECK DISEASE FOR ENT & HNS.pptxMETASTATIC NECK DISEASE FOR ENT & HNS.pptx
METASTATIC NECK DISEASE FOR ENT & HNS.pptx
 
anatomy of Prostate and prostate carcinoma
anatomy of Prostate and prostate carcinomaanatomy of Prostate and prostate carcinoma
anatomy of Prostate and prostate carcinoma
 
Ovarian classification and Management
Ovarian classification and ManagementOvarian classification and Management
Ovarian classification and Management
 

More from Kaushik Kumar Eswaran (7)

Recent advances in wound healing
Recent advances in wound healingRecent advances in wound healing
Recent advances in wound healing
 
Recent advances in pancreatic cancer
Recent advances in pancreatic cancerRecent advances in pancreatic cancer
Recent advances in pancreatic cancer
 
Pseudocyst of pancreas and benign cystic neoplasms
Pseudocyst of pancreas and benign cystic neoplasmsPseudocyst of pancreas and benign cystic neoplasms
Pseudocyst of pancreas and benign cystic neoplasms
 
Operative steps in open appendicectomy
Operative steps in open appendicectomyOperative steps in open appendicectomy
Operative steps in open appendicectomy
 
Case series of pseudocyst of pancreas
Case series of pseudocyst of pancreasCase series of pseudocyst of pancreas
Case series of pseudocyst of pancreas
 
Case reports of uncommon abdominal trauma
Case reports of uncommon abdominal traumaCase reports of uncommon abdominal trauma
Case reports of uncommon abdominal trauma
 
Chronic pancreatitis
Chronic pancreatitisChronic pancreatitis
Chronic pancreatitis
 

Recently uploaded

🌹Attapur⬅️ Vip Call Girls Hyderabad 📱9352852248 Book Well Trand Call Girls In...
🌹Attapur⬅️ Vip Call Girls Hyderabad 📱9352852248 Book Well Trand Call Girls In...🌹Attapur⬅️ Vip Call Girls Hyderabad 📱9352852248 Book Well Trand Call Girls In...
🌹Attapur⬅️ Vip Call Girls Hyderabad 📱9352852248 Book Well Trand Call Girls In...
Call Girls In Delhi Whatsup 9873940964 Enjoy Unlimited Pleasure
 
Call Girl in Indore 8827247818 {LowPrice} ❤️ (ahana) Indore Call Girls * UPA...
Call Girl in Indore 8827247818 {LowPrice} ❤️ (ahana) Indore Call Girls  * UPA...Call Girl in Indore 8827247818 {LowPrice} ❤️ (ahana) Indore Call Girls  * UPA...
Call Girl in Indore 8827247818 {LowPrice} ❤️ (ahana) Indore Call Girls * UPA...
mahaiklolahd
 

Recently uploaded (20)

Model Call Girls In Chennai WhatsApp Booking 7427069034 call girl service 24 ...
Model Call Girls In Chennai WhatsApp Booking 7427069034 call girl service 24 ...Model Call Girls In Chennai WhatsApp Booking 7427069034 call girl service 24 ...
Model Call Girls In Chennai WhatsApp Booking 7427069034 call girl service 24 ...
 
Call Girls Vasai Virar Just Call 9630942363 Top Class Call Girl Service Avail...
Call Girls Vasai Virar Just Call 9630942363 Top Class Call Girl Service Avail...Call Girls Vasai Virar Just Call 9630942363 Top Class Call Girl Service Avail...
Call Girls Vasai Virar Just Call 9630942363 Top Class Call Girl Service Avail...
 
Most Beautiful Call Girl in Bangalore Contact on Whatsapp
Most Beautiful Call Girl in Bangalore Contact on WhatsappMost Beautiful Call Girl in Bangalore Contact on Whatsapp
Most Beautiful Call Girl in Bangalore Contact on Whatsapp
 
💕SONAM KUMAR💕Premium Call Girls Jaipur ↘️9257276172 ↙️One Night Stand With Lo...
💕SONAM KUMAR💕Premium Call Girls Jaipur ↘️9257276172 ↙️One Night Stand With Lo...💕SONAM KUMAR💕Premium Call Girls Jaipur ↘️9257276172 ↙️One Night Stand With Lo...
💕SONAM KUMAR💕Premium Call Girls Jaipur ↘️9257276172 ↙️One Night Stand With Lo...
 
🌹Attapur⬅️ Vip Call Girls Hyderabad 📱9352852248 Book Well Trand Call Girls In...
🌹Attapur⬅️ Vip Call Girls Hyderabad 📱9352852248 Book Well Trand Call Girls In...🌹Attapur⬅️ Vip Call Girls Hyderabad 📱9352852248 Book Well Trand Call Girls In...
🌹Attapur⬅️ Vip Call Girls Hyderabad 📱9352852248 Book Well Trand Call Girls In...
 
The Most Attractive Hyderabad Call Girls Kothapet 𖠋 9332606886 𖠋 Will You Mis...
The Most Attractive Hyderabad Call Girls Kothapet 𖠋 9332606886 𖠋 Will You Mis...The Most Attractive Hyderabad Call Girls Kothapet 𖠋 9332606886 𖠋 Will You Mis...
The Most Attractive Hyderabad Call Girls Kothapet 𖠋 9332606886 𖠋 Will You Mis...
 
Manyata Tech Park ( Call Girls ) Bangalore ✔ 6297143586 ✔ Hot Model With Sexy...
Manyata Tech Park ( Call Girls ) Bangalore ✔ 6297143586 ✔ Hot Model With Sexy...Manyata Tech Park ( Call Girls ) Bangalore ✔ 6297143586 ✔ Hot Model With Sexy...
Manyata Tech Park ( Call Girls ) Bangalore ✔ 6297143586 ✔ Hot Model With Sexy...
 
Call Girl in Indore 8827247818 {LowPrice} ❤️ (ahana) Indore Call Girls * UPA...
Call Girl in Indore 8827247818 {LowPrice} ❤️ (ahana) Indore Call Girls  * UPA...Call Girl in Indore 8827247818 {LowPrice} ❤️ (ahana) Indore Call Girls  * UPA...
Call Girl in Indore 8827247818 {LowPrice} ❤️ (ahana) Indore Call Girls * UPA...
 
Night 7k to 12k Chennai City Center Call Girls 👉👉 7427069034⭐⭐ 100% Genuine E...
Night 7k to 12k Chennai City Center Call Girls 👉👉 7427069034⭐⭐ 100% Genuine E...Night 7k to 12k Chennai City Center Call Girls 👉👉 7427069034⭐⭐ 100% Genuine E...
Night 7k to 12k Chennai City Center Call Girls 👉👉 7427069034⭐⭐ 100% Genuine E...
 
Top Rated Bangalore Call Girls Majestic ⟟ 9332606886 ⟟ Call Me For Genuine S...
Top Rated Bangalore Call Girls Majestic ⟟  9332606886 ⟟ Call Me For Genuine S...Top Rated Bangalore Call Girls Majestic ⟟  9332606886 ⟟ Call Me For Genuine S...
Top Rated Bangalore Call Girls Majestic ⟟ 9332606886 ⟟ Call Me For Genuine S...
 
Premium Call Girls In Jaipur {8445551418} ❤️VVIP SEEMA Call Girl in Jaipur Ra...
Premium Call Girls In Jaipur {8445551418} ❤️VVIP SEEMA Call Girl in Jaipur Ra...Premium Call Girls In Jaipur {8445551418} ❤️VVIP SEEMA Call Girl in Jaipur Ra...
Premium Call Girls In Jaipur {8445551418} ❤️VVIP SEEMA Call Girl in Jaipur Ra...
 
Trichy Call Girls Book Now 9630942363 Top Class Trichy Escort Service Available
Trichy Call Girls Book Now 9630942363 Top Class Trichy Escort Service AvailableTrichy Call Girls Book Now 9630942363 Top Class Trichy Escort Service Available
Trichy Call Girls Book Now 9630942363 Top Class Trichy Escort Service Available
 
Call Girls in Delhi Triveni Complex Escort Service(🔝))/WhatsApp 97111⇛47426
Call Girls in Delhi Triveni Complex Escort Service(🔝))/WhatsApp 97111⇛47426Call Girls in Delhi Triveni Complex Escort Service(🔝))/WhatsApp 97111⇛47426
Call Girls in Delhi Triveni Complex Escort Service(🔝))/WhatsApp 97111⇛47426
 
Call Girls Gwalior Just Call 8617370543 Top Class Call Girl Service Available
Call Girls Gwalior Just Call 8617370543 Top Class Call Girl Service AvailableCall Girls Gwalior Just Call 8617370543 Top Class Call Girl Service Available
Call Girls Gwalior Just Call 8617370543 Top Class Call Girl Service Available
 
Top Rated Hyderabad Call Girls Erragadda ⟟ 9332606886 ⟟ Call Me For Genuine ...
Top Rated  Hyderabad Call Girls Erragadda ⟟ 9332606886 ⟟ Call Me For Genuine ...Top Rated  Hyderabad Call Girls Erragadda ⟟ 9332606886 ⟟ Call Me For Genuine ...
Top Rated Hyderabad Call Girls Erragadda ⟟ 9332606886 ⟟ Call Me For Genuine ...
 
Call Girls Service Jaipur {8445551418} ❤️VVIP BHAWNA Call Girl in Jaipur Raja...
Call Girls Service Jaipur {8445551418} ❤️VVIP BHAWNA Call Girl in Jaipur Raja...Call Girls Service Jaipur {8445551418} ❤️VVIP BHAWNA Call Girl in Jaipur Raja...
Call Girls Service Jaipur {8445551418} ❤️VVIP BHAWNA Call Girl in Jaipur Raja...
 
Call Girls Vadodara Just Call 8617370543 Top Class Call Girl Service Available
Call Girls Vadodara Just Call 8617370543 Top Class Call Girl Service AvailableCall Girls Vadodara Just Call 8617370543 Top Class Call Girl Service Available
Call Girls Vadodara Just Call 8617370543 Top Class Call Girl Service Available
 
Top Rated Hyderabad Call Girls Chintal ⟟ 9332606886 ⟟ Call Me For Genuine Se...
Top Rated  Hyderabad Call Girls Chintal ⟟ 9332606886 ⟟ Call Me For Genuine Se...Top Rated  Hyderabad Call Girls Chintal ⟟ 9332606886 ⟟ Call Me For Genuine Se...
Top Rated Hyderabad Call Girls Chintal ⟟ 9332606886 ⟟ Call Me For Genuine Se...
 
VIP Hyderabad Call Girls Bahadurpally 7877925207 ₹5000 To 25K With AC Room 💚😋
VIP Hyderabad Call Girls Bahadurpally 7877925207 ₹5000 To 25K With AC Room 💚😋VIP Hyderabad Call Girls Bahadurpally 7877925207 ₹5000 To 25K With AC Room 💚😋
VIP Hyderabad Call Girls Bahadurpally 7877925207 ₹5000 To 25K With AC Room 💚😋
 
Call Girls Raipur Just Call 9630942363 Top Class Call Girl Service Available
Call Girls Raipur Just Call 9630942363 Top Class Call Girl Service AvailableCall Girls Raipur Just Call 9630942363 Top Class Call Girl Service Available
Call Girls Raipur Just Call 9630942363 Top Class Call Girl Service Available
 

Diagnostic approaches in cup(carcinoma of unknown primary

  • 1. Diagnostic approaches In CUP Neck(Carcinoma of Unknown Primary) DR.E.KAUSHIK KUMAR DEPARTMENT OF GENERAL SURGERY STANLEY MEDICAL COLLEGE
  • 2. • குறள் 71: அன்பிற்கும் உண்டைோ அடைக்குந்தோழ் ஆர்வலர் புன்கண ீர் பூசல் தரும். : அன்பிற்கும் கூைப் பிறர் அறியோமல் தன்டை மூடி டவக்கும் கதவு உண்டைோ? இல்டல. தம்மோல் அன்பு சசய்யப்பட்ைவரின் துன்பத்டதக் கோணும்டபோது வடியும் கண்ண ீடே அன்பு உள்ளத்டதக் கோட்டிவிடும்.
  • 3. AIM • Clarifying the histology of the nodal metastases • Detecting the primary.
  • 4. History • Family and Personal history, including history of previous malignancy both in the head and neck, and elsewhere • History of previous radiation • History of a previous facial or cervical skin lesion that has disappeared • History of any upper aero-digestive tract related symptoms (sore throat, otalgia, hoarseness, dysphagia, hearing loss or epistaxis) • Previous operations (breast, abdomen, chest, etc.).
  • 5. Clinical Evaluation • Scrupulous physical and fiber-optic evaluation of the head and neck district including palpation of the oral cavity, oropharynx, and base of the tongue, and search for scars in the head and neck indicating previous surgery. • Examination of the neck, which includes site, size, mobility, and relationship of the node(s) to the adjacent structures. • Complete physical examination for abnormalities elsewhere: breast, axilla, groins, testicles, abdomen.
  • 6. Investigations • FNAC • Imaging • Endoscopy • Molecular assays • Examination under General Anaesthesia
  • 7. FNAC • Recommended if the above evaluation does not detect any primary. • Repetitive non-diagnostic FNACs- an indication for an open biopsy, intra-operative histologic examination and possible neck dissection • Performed by experienced specialists • Allow detection of the primary in more than 50% of patients
  • 8. IMAGING • Head and Neck- CT, MRI • CECT Thorax – Trachea – Oesophagus – Lungs • CECT Abdomen – Liver – Ovary – Testes – Prostate
  • 9. PET-CT • Overall staging accuracy -69-78% • Positive predictive value -56-83% • Negative predictive value-75-86% • Sensitivity-63-100% • Specificity -90– 94% • With negative routine clinical examination, CT, and MRI, PET scan allows detection of primary tumours in 5-43% of patients. • Higher rates of primary tumour detection-non-head and-neck CUP or histologies other than SCC
  • 10. • The resolution of the PET scan limited to 5 mm • Tumours of the supraglottic region and Waldeyer’ s tonsillar ring-most difficult to be diagnosed with FDG-PET – low tumour volume in small, superficial lesions – the presence of normal lymphoid tissues – accumulation of FDG secreted by salivary glands to saliva pools in the valleculae and pyriform sinuses – Improved detection may probably be achieved with a 12-h pre-study fast,
  • 11. • Ideally, biopsies should be performed after PET scan – Sampling of the areas suspected in PET – Avoids false positive PET-scans at biopsy site. • Exclusion of other metastases • Post-radiotherapy neck evaluation • Subsequent monitoring
  • 13. MOLECULAR ASSAYS • Recently proposed to differentiate the potential primary site. • Detection of the Epstein-Barr virus (EBV) with the use of in situ hybridization in metastatic lymph nodes may suggest nasopharyngeal tumour • Human Papilloma virus (HPV) detected by polymerase chain reaction may indicate oropharyngeal cancer • Microsatellite mutation analysis of metastatic nodal tissue and samples of normal pharyngeal mucosa • In CUP the primary acquires a metastatic phenotype soon after transformation and remains small, either by inborn errors leading to involution of the primary, or due to extremely slow growth rate • Inhibiting the growth of the primary by metastases
  • 14. Examination under general anaesthesia • When the primary is not dectected, an evaluation under general anaesthesia is mandatory. • Biopsies are taken from all sites suspicious at the clinical and imaging evaluation, and blindly from the sites of possible origin of the primary – base of tongue – tonsil or tonsillar fossa – pyriform sinus – nasopharynx.
  • 15. • Another option is open biopsy • Increased risk of distant metastases following this procedure has been suggested • Detection rate – CT scan -15-20% – Panendoscopy with biopsies -up to 65% • The most common sites of primary (82%) – Tonsil – Base of tongue
  • 16.