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Paper text:
mycosis fungoides ( mf ) is a cutaneous , extranodal , insidious non - hodgkin t - cell lymphoma [ 1 , 2 ] .
almost any location in the body can be infiltrated by mf , including the oral cavity and the gastrointestinal ( gi ) tract .
oral cavity and gi involvement of mf are rare as separate entities [ 3 , 4 , 5 ] .
we present one case of mf with both oral and visceral involvement , with complication of intestine perforation after treatment .
a 38-year - old man with congenital ichthyosis and presumed psoriasis presented in late 2015 with erythroderma , numerous plaques , and tumors affecting his body and face .
he was admitted for methicillin - resistant staphylococcus aureus skin infection and treated with whirlpool therapy and intravenous antibiotics .
initial histology was consistent with psoriasiform epidermal hyperplasia with spongiosis . although the biopsy showed exocytosis and lymphocytes , there was no large - cell transformation .
the t - cell analysis showed cells with cd3 and some cd4 expression and without cd7 or cd8 expression .
most of the cells expressed tcr-. no gene rearrangements were noted . in situ hybridization for ebv rna ( eber ) was negative .
he returned to his home country after 2 months but re - presented 1 month later with dysphagia , abdominal pain , and a 20-pound weight loss .
his mouth was remarkable for two linear white plaques with an erythematous base on the pharynx above the uvula .
he had a geographic tongue with lack of pili and white - to - yellowish plaque - like lesions along the midline and left lateral anterior dorsal surface ( fig 1 ) .
biopsy of the anterior dorsal tongue was filled with atypical lymphocytes extending to the basal layer of the epithelium .
the malignant cells were double negative for both cd4 and cd8 , expressed bf-1 , and had some labeling for t - cell intracellular antigen , granzyme b , and cd56 .
this was consistent with epidermotropic cutaneous t - cell lymphoma . restaging imaging showed lymphomatous involvement in his small intestine ( fig 2 ) .
he received 12 gy of palliative radiation to his oropharynx , 1 dose of brentuximab vedotin anti - cd30 antibody ( 1.8 mg / kg i.v . ) , and one cycle of cyclophosphamide - etoposide - vincristine - prednisone ( ceop ) .
the patient presented to the emergency room with acute abdominal pain 2 weeks after the brentuximab and ceop administration .
his ct scan showed significant progression of tumor involving the intestine , evidence of obstruction , and intestine perforation with free intraperitoneal air in the region of the small intestine .
he ultimately had improvement in functional status and skin tumor burden . after completing two cycles of the gemcitabine nearly 5 months after his oral lesions had initially appeared and 3 months after the perforation
he was subsequently placed back on a second cycle of brentuximab vedotin after biopsy of the right forearm had shown mf with atypical lymphocytes that were positive for cd3 and cd7 , mostly negative for cd4 and cd8 , and expressed cd30 in approximately 45% of lymphocytes .
we report the first case of simultaneous involvement of mf in the oral cavity and small intestine .
however , this case provides insight into the disease process and the complications of lymphomas with gi tract involvement .
the mf disease process has a relatively predictable pattern of three phases : erythematous or eczematous rash , infiltrated plaques , and cutaneous tumors . ultimately , the mf disease process results in diffuse visceral and lymphatic involvement [ 3 , 4 , 6 ] . this outcome is the hallmark of end - stage disease , which is characterized by atypical lymphocytes that lack the epidermotropism of early - stage mf
. oral cavity involvement of mf is a rare event , a predictor of poor prognosis , and found in late - stage disease .
there were only 42 reported cases of oral mf including our patient ; most cases of mf in the oral cavity have been described as affecting the tongue and palate , as in our patient [ 3 , 4 , 5 , 6 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ] .
extranodal non - hodgkin lymphoma most commonly occurs in the gi tract , with the small intestine being the most common site of involvement .
there have been reports of mf cases throughout the gi tract , including the small intestine ( table 1 ) [ 3 , 4 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ] .
the most common site was the small intestine , as seen in our patient . the majority of cases in the small intestine presented with abdominal pain and ultimately experienced death up to 6 months after presentation with gi mf .
our patient presented similarly , with advanced - stage disease and with abdominal pain shortly after treatment with radiation , brentuximab , and ceop .
he had initial resolution of his skin and oral lesions on gemcitabine , but had disease recurrence with resulting perforation less than 6 months later .
the complications of gi involvement include hemorrhage , obstruction , and perforation [ 6 , 22 , 44 , 45 ] .
perforation from lymphoma involvement in the gi tract was a well - known complication , with the majority occurring as the first sign of gi involvement and not as a result of antineoplastic treatment [ 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 ] .
the small intestine was the most common site of perforation [ 53 , 54 ] .
perforation as a result of therapy can occur shortly after treatment , usually within a few weeks , as in our patient [ 53 , 54 ] .
the risk of perforation from the cytotoxic agent seems to be less than that of the tumor 's presence itself , but clinicians should nonetheless be cautious in treating patients with lymphoma in the gi tract .
although patients with mf are at risk of secondary lymphomas , the timing and good response to brentuximab and gemcitabine suggested that the lesions were mf and that the perforations were likely a result of the antineoplastic agents . to our knowledge
, there have been three case reports of intestinal perforation from mf involvement of the small intestine [ 22 , 33 , 41 ] .
one of the cases was described in the german - language literature . of the other patients presented in the two english - language case reports ,
however , the second patient presented with perforation of the small intestine after prednisone treatment in a similar fashion to our patient . in conclusion ,
the latter was accompanied by abdominal pain and resulted in serious , life - threatening bowel perforations that had been preceded by combination therapy with antibody and multi - agent chemotherapy .
the participant provided written informed consent for use of his case and images per university of texas md anderson cancer center ( utmdacc ) guidelines .
the authors certify that they have no sponsorship or funding arrangements relating to their research .
extracutaneous involvement in mycosis fungoides ( mf ) carries a poor prognosis . 
 oral and gastrointestinal ( gi ) tract lesions are both rare locations of disease . 
 we describe the clinical findings of one case with oral and gi mf complicated by perforation after systemic antineoplastic treatment , and review the relevant literature . 
 the patient had a 1-year history of mf before development of tongue and palate tumors . 
 he was treated with local electron beam radiation , but re - presented to the hospital after what was found to be small intestine perforation following systemic antineoplastic therapy . 
 the case reveals key insights into the progression and complications of lymphomas with gi tract involvement .